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In the Asparagus Patch.

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An early illustration of Asparagus from Duhamel du Monceau’s Traité des arbres et arbustes, vol. 1: t. 31 (1755); image from http://www.plantillustrations.org. Asparagus was among the earliest European vegetables to be brought to the New World.

As a child, the wispy, ferny fronds of wild Asparagus were always rather magical to me. It was as if the staid crop had let its hair down as it roamed the ditches and roadsides. It should not be surprising that Asparagus is widely feral; it has been here for a while. Asparagus has been recognized as a vegetable for millennia and apparently was planted in some of the first new world vegetable gardens, possibly because of its early-season arrival to the table, its hardiness and perennial habit, and its purported medicinal properties. In addition, its original native Western Europe seaside habitat may have preadapted it to road salt.

Asparagus was listed among the vegetables in William Penn’s colony in 1685. By 1747, Peter Kalm found it growing wild in various places, including along the Hudson north of Albany. Jefferson included abundant observations on its planting in his garden notebooks starting in 1767, and it was being sold commercially in New England in the same century. It was widely naturalized in NY by the early 1800s, and, by the mid 1800s, it was being grown extensively, including in 10-20 acre fields on Long Island for sale in NYC.

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A late 19th or early 20th century Massachusetts asparagus farm, from Hexamer’s Asparagus : its Culture for Home Use and for Market : a Practical Treatise on the Planting, Cultivation, Harvesting, Marketing, and Preserving of Asparagus. Large asparagus farms served major East Coast cities.

As is often the case with newly introduced plants, for many years Asparagus apparently had few enemies. However, in 1862 New York State Entomologist Asa Fitch began his annual report with this line, “Much the most important entomological event in our State the present year has been the appearance upon the asparagus on Long Island of an insect new to us in this country, and doing great injury to this important crop, threatening even its total destruction.” The Common Asparagus Beetle had arrived.

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The illustration that accompanied Asa Fitch’s 1862 description of the Common Asparagus Beetle upon its first recorded arrival to North America, from the 8th Report on the Noxious and Other Insects of the State of New York. Damage was apparently quick and extensive.

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The Common Asparagus Beetle in action, as illustrated in Hexamer’s work. The beetles seem to attack the stalk and head while the grubs appear to spend more time eating the leafy fronds.

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A sickly, beetle-damaged Asparagus stalk. Adults and grub feed directly on the plant, and extensive egg-insertion may stunt stalk growth.

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The Common Asparagus Beetle.

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On heavily occupied plants, the activity can be crowded.

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Mating Common Asparagus Beetles on Asparagus. The wet-looking scrapes on the Asparagus stalks are from its feeding.

After some research, Fitch concluded that the Common Asparagus Beetle (Crioceris asparagi) had probably landed on these shores some time in 1857 or 1858. He could offer little by way of control except, after dismissing the use of skunks (who did seem to enjoy beetle fare but were “in such bad odor”), the use of free-ranging fowl. For the next two years, growers apparently despaired but then a “small, shining black parasitic fly” appeared as a “deliverer” and the destruction abated somewhat. The mysterious parasite apparently then disappeared, and the beetle continued to spread, probably reaching our area (Columbia County, NY) around the turn of the century. In 1909 (see this paper), the parasite was  finally captured and identified as the small wasp Tetrastichus aparagi. Subsequently, and not surprisingly in retrospect, this wasp was found to be identical to T. coeruleus, a wasp known to parasitize the Common Asparagus Beetle in its native Old World homeland.

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A probable Tetrastichus coeruleus, the wasp that saved the Asparagus crop.

The wasp has not disappeared again, and it is apparently crucial to controlling Common Asparagus Beetles. Estimates are that it kills approximately three quarters of the eggs produced by this beetle. Interestingly, American economic entomologists, struggling with the late 19th century rampages of the Asparagus Beetle, seemed somewhat baffled that Europeans could not provide them with any adequate control measures. It now seems likely that, with this little wasp already ‘on the job’, Europeans rarely needed extra measures.

Before describing some of what is known of the life cycles of both wasp and beetle, it’s important to emphasize the fact that Asparagus is a perennial; it may produce a crop for a decade or more. Unlike the case with annual crops, asparagus fields are not being ploughed under and moved every year, and so populations of both pest and parasite can build up over several years.

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Asparagus is a perennial crop that may be harvested for up to a dozen years. This allows predator/pest communities to develop over time.

The Common Asparagus Beetle overwinters in the soil as an adult. These beetles then emerge in the Spring and begin to feed on the rapidly growing asparagus shoots. Soon, rows of their tiny, neat eggs begin to appear on asparagus stalks, (The only analogy I can think of for the appearance of the eggs is that of a school of shark fins cutting through an asparagus ocean… OK, that probably doesn’t help.) After a week or so, these hatch into black-headed, grey-bodied grubs who feed avidly for a couple of weeks then pupate in the soil for a dozen days or so, re-emerging as the second generation a bit more than a month after their parents. These beetles go on to produce another generation, and, it is those beetles or their progeny who then overwinter.

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A Common Asparagus Beetle grub together with eggs of the same species.

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Several Common Asparagus Beetle grubs on a young Asparagus frond that they have nearly stripped of its outside layer.

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A Common Asparagus Beetle among eggs of the same species. I’m guessing the yellowish egg is recently laid, but I may be wrong.

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Although egg laying on Asparagus should be the norm, this beetle decided to try grass. Since young larvae appear to travel in search of the appropriate Asparagus plant for feeding, perhaps these future hatchlings will make it to a nearby Asparagus stalk.

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Common Asparagus Beetles reportedly overwinter as adults in litter, under tree bark, and in the somewhat hollow stems of cut Asparagus such as shown here.

While the adults scar the surface of the large stalks and eat the ‘scales’ of the heads, the grubs seem to favor the finer vegetation of the branching asparagus ‘ferns’, and can quickly girdle and strip smaller plants. The action of the adults, while apparently not as immediately dramatic, can scar and stunt the asparagus shoots growth, sometimes causing the stalk to do a complete loop the loop and rendering them unfit for sale.

Meanwhile, the wasp has been passing winter in the pupae of the eggs it parasitized the previous year. It soon emerges and begins its work. One of the characteristics that apparently makes this wasp so effective in control is that it is not only a parasite, it is also a predator. The adult wasp both consumes and lays its eggs in (that is, ‘oviposits’) the beetle’s eggs.

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A sequence of shots showing the parasitic wasp approaching and sensing an egg, inserting its ovipositor in two different locations on the same egg, and apparently eating or at least tasting some of the content. The glistening circles evident on a couple of eggs are the insertion points. The ovipositor comes out of the central ventral portion of the abdomen, not the tip and is visible in a couple of the pictures.

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The somewhat deflated eggs visible in this shot may be the work of a hungry wasp, although I still need to insure that I can tell hatched from consumed eggs.

The wasp’s general behavioral sequence, based on the aforementioned early 20th century observations and a more recent European paper, is that a wasp approaches an egg and ‘sniffs’ or drums it with its antennae. It then makes the choice to eat, oviposit in, or reject the egg. Younger eggs seem to be favored for eating, while older eggs are favored for oviposition, although, on average, most eggs are rejected outright.

Egg consumption is an interesting behavior. Rather than simply walking up to an egg and taking a bite, the wasp seems to macerate the contents through rhythmical insertions of its ovipositor (see this video of the same wasp pictured here) and then lap up the contents. According to the above mentioned papers, actual oviposition involves a more tranquil insertion maintained for “several minutes”.

One last twist involves what happens next: the parasitized beetle egg hatches and the grub develops normally and pupates in the soil. This was clearly a head scratcher for early observers. But patience finally revealed the end result – the pupae never hatch, at least they don’t produce an adult beetle, instead, up to 10 wasp larvae emerge from the hollowed out beetle pupa. The wasp thus appears to practice delayed development, coordinating its own developmental rush to the pupation stage of the beetle. One possible advantage of this is that the young wasps can overwinter as larvae and/or pupae snug within the small underground cell originally created by the parasitized beetle larvae. The adult wasps then emerge in spring to renew the cycle.

The Spotted Asparagus beetle is commonly found with the Common Asparagus Beetle although, aptly enough, it is usually less common. The beetle in the lower image has decided to hang out on an adjacent weed rather than the Asparagus itself.
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The Spotted Asparagus Beetle usually puts its eggs on the Asparagus flower bud or berry rather than the stalk, so I’m guessing that is who laid these eggs, but I wasn’t present at their arrival.

The Common Asparagus Beetle and the parasitic wasp are not the only visitors to Asparagus. The Spotted Asparagus Beetle (Cioceris duodecimpunctata) arrived somewhat later and has not been as damaging. Its eggs are laid on the Asparagus berries, and its larvae apparently confine their feeding to that part of the plant. While often present, they seem to be generally less abundant than the Common Asparagus Beetle. Another species of wasp is thought to parasitize them. True Bugs sometimes also feed on the eggs, while the maggots of certain flies are known to bore into the Asparagus stems. In addition, passersby regularly alight on the Asparagus stalks, as they would on almost any piece of vegetation. There’s obviously a lot more going on here, but that’s enough for one posting!

Thanks to my colleagues at Hawthorne Valley Farm and the Hudson Valley Farm Hub for tolerating my snooping.

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This wasp, a different species from the one pictured earlier, spent a while excitedly clambering over a grub-laden Asparagus frond but, in the end, it just flew away.
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This fly was moving up and down an egg-spotted Asparagus stem, apparently cleaning up some of the spilled juices.
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So far as I saw, this fly never did anything but perch. Several fungus-filled fly mummies were found nearby. I don’t know the species of fly, but perhaps these were simply using the Asparagus’ high and handy perches.
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This nymph of a True Bug patrolled some egg rows, apparently (although not definitively) sucking out the contents of some of them… think food-filled balloons.
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And, amongst it all, a spider waited patiently; the Asparagus was as good a place as any for some hunting.
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This red mite seemed to be sucking on a beetle egg, but perhaps it was only imbibing nearby plant juices.
 
 

Columbia County Moths

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At this time of year we have the opportunity to observe moths not only at our porch lights, but at flowers as well. A number of moths, including the American Ear Moth (Amphipoea americana) shown above, extract nectar from flowers in the light of day. However, most moth species await dusk or dark to come out from their resting places. Nectaring is not a behavior of all moth species. Some, like the famous Luna Moth (Actias luna) and other Giant Silkworm Moths, do not feed at all as adults and therefor have short lives. In Columbia County, we have just a brief period in spring where we may see the week-long-lived Luna Moth at rest in the forest, or by a porch light. Moths’ attraction to light is a bit of a mystery, but it may relate to their use of the moon for orientation. In any case, this attraction has allowed us to study Columbia County moths by using specialized lights to attract a great diversity of them.

 

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A Luna Moth seen June 2nd, 2016 in Austerlitz, N.Y

 

 

The Moth Tally

One would think that tallying the species of moths in a rural county in upstate New York would be a feasible task. Columbia County is about 650 square miles of land, largely composed of Oak-Hickory and Northern Hardwood (with hemlock and/or pine) forest types. Yes, there are swamps, rocky barrens, shrublands, meadows, farmland and various other habitats; and elevation ranges from about 10 ft. by the Hudson River to over 2,000 ft. at Harvey Mountain; but, it’s just another rural county in upstate New York. How many moth species can this place have?

Well, after two years of simply observing or conducting official moth surveys; asking my girlfriend to spend many a Friday night in the woods or by the house beside a moth light; the answer is that I have no idea. For now, our number is about 560 species of moths in the county (determined with the help of other accredited observers), but give it a week or two, and we may have 600 or more. Nearly every time out mothing, whether it’s a place I have surveyed before or not, I find one, two, or ten new species for our list. With no end to the tally in sight given the continued occurrence of many new species on each outing, I’m excited to see just how big this list will get and what the next survey will bring in.

 

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A starlit moth survey at an Ancram, N.Y. meadow

 

Being that moths are a very diverse group of insects, it’s no surprise that we apparently are far from determining their diversity in our county. Both moths and butterflies belong to the order Lepidoptera, the second largest insect order. There are about 13,000 species of Lepidoptera in the United States, with roughly 5,000 of them residing east of the Mississippi. New York has a long history of studying moths. In 1916, there were 2,304 documented species of moths statewide. The species list was the work of many observers, including entomologists Edward Doubleday, Augustus R. Grote, and Joseph Lintner, all who made considerable contributions to our knowledge of the state’s Lepidoptera; some 26 other observers throughout the state also contributed. A later estimate put the number at about 3,300 species statewide. Neighboring New York, John Himmelman, author of Discovering Moths, notes Connecticut as having about 2,300 species of moths.

To get an idea of what our total moth diversity might be in Columbia County, we can look at the results of some moth studies from smaller regions. Work at the 318 acre Hunt-Parker Sanctuary in Westchester County, N.Y. documented 450 species of moths from 2002 to 2005. Another study in several northwest Vermont counties used surveying as well as historical records and collections to assess moth diversity. They documented nearly 1,700 species.

Perhaps the most comparable assessment took place in the Ashokan region (the town of Olive, N.Y.) of the Catskill Mountains. The study took place over the course of three summers, from the spring of 1992 to fall of 1994. Instead of looking at the diversity of all moths, the study focused on the Sphinx Moth (Sphingidae) and Owlet Moth (Noctuidae) families. The region is quite close to Columbia County, about 20 miles south west. Elevation there ranges from about 700 ft. to 3,000 ft.; it hosts a large portion of the Ashokan Resevior, but otherwise is well forested with mixed development. The area is about a tenth the size of Columbia County. These researchers documented 358 Owlet Moth species compared to the 146 we have seen in Columbia County. If we make the assumptions that they saw all of the Owlet Moths present, that we have as many such species here in Columbia County, and that the ratio of Owlet Moths to non-Owlet Moths is constant, then we can roughly estimate Columbia County moth diversity at about 1,350 species. That number may be too high, as the Ashokan region hosts a variety of rare plants and has high elevation ecoregions that are absent here. Both of these characteristics may enhance moth diversity. However, that estimate could also be too low, because our study area is 10 times that of the Ashokan region. Either way, it gives us a ball park figure and suggests that we are not even half way there in assessing Columbia County moth diversity.

One difficult aspect of determining moth diversity anywhere is the much overlooked very small moths, called micromoths. Also known as microlepidoptera, these specimens represent a majority of moth species in the United States. The caterpillars of these small moths are unlikely to be seen by the human eye as most are endophagus (they bore into, or are hatched within, a plant’s stem, wood, fruit or leaves); some even feed on dead animals, fungi, or parasitize other insects; others are aquatic, feeding on algae in streams or waterlily in ponds and lakes. Because of their small size, there is relatively little known about micromoths. There may be undescribed species of them here in New York State, or even within Columbia County. We have seen a great number of these small creatures during our surveys, and we do our best to document them, but, even with the help of macro photography, it seems impossible to identify many of them due to their size and the limited identification resources.

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This micromoth, the Orange-headed Epicallima (Epicallima argenticinctella), is about 6mm in length. Its caterpillars can be found under the bark of elm trees

 

I have to admit, before I was introduced to mothing by wildlife biologist Conrad Vispo, I knew of three types of moths: the Luna Moth, the clothes moths (the ones you fend off with moths balls) and the ‘none of the above’, which were, in my mind, all gray and nondescript. It took only a survey for me to discover their beauty and diversity. There are endless colors, shapes, and textures; although all moths are covered by scales (Lepidoptera is Latin for “scale wing”), some appear to be fury while others are smooth and glossy. Some moths have patterns that are so artistic and unique that it is hard to imagine the evolutionary paths that made them. Our program has done some mothing with students, and they have made up their own names for some species we’ve seen, including the “Dragon Moth”, the “Jet Fighter”, and the “Strawberry-lemonade Moth”.

 

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The strawberry-lemonade themed Rosy Maple Moth (Dryocampa rubicunda) is common in Columbia County and can be seen in May and June

 

 

The County’s Rare Moths

There are moth species that we see in great abundances during our surveys, like the Tent Caterpillar Moth (Malacosoma sp.; there are in fact two species in our region) and the Common Idia (Idea aemula), whose caterpillars feed on dead leaves. On the other hand, there are rare moths here as well. A moth may be rare because their larval host plant is uncommon. In the case of the Barred Granite (Speranza subcessaria), an uncommon moth here, their host plants, Gooseberry and Currant, were deliberately removed from our landscape during the early 20th century. These plants were a threat to lumber production because they were an intermediate host of a disease that affected White Pine, a once economically important tree in Columbia County. Other factors, such as environmental pressures caused by pesticides, light pollution, development, invasive species, or deer herbivory, may negatively affect a moth species and contribute to its rarity. A third possibility is that a moth species is simply difficult to survey for and is therefore seldom noticed. For example, I have seen a number of Tomato Hornworm caterpillars in our garden, but I have never seen its adult form (the Five-spotted Sphinx Moth), even though I survey for moths around my home regularly.

Below are a few examples of Columbia County’s rare moths. In our many surveys, we have seen these species just once.

 

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The Finned-willow Prominent (Notodonta scitipennis) is uncommon both locally and throughout its range. Its larvae feed on Poplar and Willow. Although these plants are certainly abundant in parts of Columbia County, it remains to be a rare moth. Seen in Claverack, N.Y.

 

 

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The Barred Granite is not a regular sight in Columbia County. The moth flies for just one month. Their caterpillars are specialized and feed only on Gooseberry and Currant. Seen in Austerlitz, N.Y.

 

 

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The wildly patterned Glorious Habrosyne (Habrosyne gloriosa) is uncommon throughout its range. What their caterpillars feed on is not known to science, but Rubus species, including Blackberry and Raspberry, are likely. Seen in Austerlitz, N.Y.

 

 

 

The Sphinx Moths

Sphingidae, commonly referred to as Sphinx Moths, is just one of many moth families; their species in our region represent only a small fraction (less than 4%) of our moth diversity. However, Sphinx Moths are conspicuous creatures. They are large, often strikingly colored or shaped; many species nectar from flowers and are able to hover in place, giving them common names like “hawk moths” and “hummingbird moths”. There are diurnal, crepuscular (active at dusk and dawn) and nocturnal species in our region. At 1,400 species worldwide, they are one of the best studied groups of insects in the world, partly due to their large size. In the northeastern U.S., there are nearly 40 Sphinx Moth species, of which we’ve documented 20 in Columbia County; with three subfamilies, two of them—commonly referred to as the Large Sphinx Moths (Sphinginae) and the Small Sphinx Moths (Macroglossinae)—are regular visitors to tubular flowers and can be seen nectaring during the day or at dusk. A third subfamily in our region, the Eyed Sphinx Moths (Smerinthinae), have scalloped wings and robust bodies; on their hind wings, most species have blue-filled circular spots resembling eyes.

 

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The diurnal Snowberry Clearwing (Hemaris diffinis), of the Macroglossinae subfamily, nectars at a Monarda flower

 

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A Laurel Sphinx (Sphinx kalmia), of the Sphinginae subfamily, rests on goldenrod

 

 

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A Modest Sphinx (Pachysphinx modesta), of the subfamily Smerinthinae, shows its eye-like spots

 

Members of this group host the longest probosces (a tubular mouthpart used for feeding) of any moth or butterfly in the world. In 1862, after observing Madagascar’s large Star Orchid (Angraecum sesquipedal), Charles Darwin wrote, “In Madagascar there must be moths with probosces capable of extension to a length of between ten and eleven inches”. Darwin’s prediction was verified some 20 years after his death, when a very large Sphinx Moth, Xanthopan morganii praedicta (sometimes referred to as Darwin’s Moth), was discovered in Madagascar; it had a foot-long proboscis that pollinated the orchid’s lengthy nectar spur. The interaction between this strange orchid and its unique pollinator has become a classic example of coevolution; both specimens have reciprocally affected each other’s evolution and now rely on one another to survive.

Although there are no Sphinx Moths in our region that could pollinate such a flower, I have seen a Pawpaw Sphinx (Dolba hyloeus) in Austerlitz, N.Y. nectaring with a roughly 40mm long proboscis; impressive, but hardly comparable to that of Darwin’s moth.

 

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The nocturnal Xanthopan morganii of Madagascar uses its 12-14 inch proboscis to feed from the lengthy nectar spur of a Star Orchid

 

 

Attracting Sphinx Moths

A great way to attract certain Sphinx Moths is by providing their sought-after flowers in your garden or around your home. In my experience, the hands-down favorite native flower of a number of Sphinx Moths is Monarda fistula, commonly called Wild Bergamot, or Bee Balm. It’s native to every state in the contiguous U.S. except California and Florida, and the flower is also a favorite of many butterflies and other pollinators. The plant seems to prefer well-drained soils and a good amount of sun. If conditions are right and there is a good pulse of flowering, these Monarda patches can be incredibly active with Lepidopterans, including Sphinx Moths; depending on the species, one can observe them nectaring during the day or at dusk. Sphinx Moths like the Hummingbird Clearwing (Hyles thysbe), Snowberry Clearwing and Gallium Sphinx (Hyles gallii) will frequently visit Monarda in daylight hours. Other species, including the Pawpaw Sphinx (Dolba hyloeus), the Laurel Sphinx, and other large and small Sphinx Moths, can be seen nectaring these flowers at dusk. Small amounts of fresh manure will also attract some Sphinx Moths; they will consume liquids from the manure and extract the salts and amino acids.

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An Ancram, N.Y. Gallium Sphinx at a Monarda flower nectaring

 

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This Nessus Sphinx (Amphion floridensis) is extracting nutrients from manure at Hawthorne Valley Farm

 

 

Sphingidae Conservation

Entomologists who have been studying and observing moths for decades in the northeastern U.S. and southeastern Canada unanimously agree that populations of the large-sized moths, including Sphinx and Giant Silkworm Moths, are collapsing. Species once present or even abundant just decades ago are now reduced or even absent from locales observed. There are various pressures that collectively are causing this decline, such as excessive deer drowsing, habitat destruction, climate change, light pollution, reduction of early successional habitats and other anthropogenic influences.

The decline of Sphinx and Giant Silkworm Moths has been occurring for a long time in the Northeast. In 1906, decades after the invasion of the nonnative and destructive (responsible for mass tree defoliation/mortality) Gypsy Moth (Lymantria dispar), a parasitic Tachinid fly native to Europe was intentionally introduced in our region. This fly then parasitized caterpillars not only of this invasive species of moth, but of a great number of native moth species as well. Because the Gypsy Moth’s caterpillars occur in forests for just a short while, during the remainder of the year the fly must seek out other caterpillar species to parasitize. Lepidopterists (those that study moths and butterflies) in our region from the 1950s to the 1970s witnessed firsthand the rapid decline of Giant Silkworm Moths and a number of species of Sphinx Moths due to this introduced parasitic fly.

In the 1920s and 30s, Columbia County was on the ‘front-line’ of Gypsy Moth control, many 1000s of pounds of insecticides were sprayed in hopes of managing Gypsy Moth populations. More recently, in the past couple decades, millions of acres of eastern forests have been aerially sprayed with insecticides to suppress Gypsy Moth outbreaks. Because these chemicals specifically affect Lepidoptera larvae, this spraying has had lethal impacts on various species of moth and butterfly caterpillars and is a serious threat to rare Lepidoptera in our region.

 

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An Austerlitz, N.Y. Gypsy Moth

 

 

We can get a glimpse of historical moth abundances by looking at old insect collections. The Farmscape Ecology Program was donated some preserved moths collected from Columbia County in the 1950s. There are several species in the collection that we have not seen here, not in my two years nor during Conrad Vispo’s previous surveying for moths. Two online resources that verify public reports of Lepidoptera sightings also have no reports of these moths in the county. These species include the Tulip-tree Silkworm (Callosamia angulifera), the Great Tiger Moth (Arctia caja), and the White-lined Sphinx (Hyles lineata). How common these moths were in Columbia County some 60 years ago is not known, but it’s a fair assumption that their populations here have either been extirpated or significantly reduced.

The most common Sphinx Moth in our Columbia County surveys by a long shot has been the Waved Sphinx (Ceratomia undulosa). It’s a very large moth (wingspan to 110mm) and has waved markings and some yellow scales throughout its body if you look closely. Their larvae feed primarily on ash trees, which face certain decline as the recently introduced Emerald Ash Borer infects a higher percentage of ash in our state each year. Although ash makes up only 6-7% of Columbia County’s trees, they are much depended on by a number of Sphinx Moths found in the county, including the Waved Sphinx, the Laurel Sphinx, the Twin-spotted Sphinx (Smerinthus jamaicensis), and other Sphinx Moths that may or may not reside here. There is an uncertain future for these moths in Columbia County.

 

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A Waved Sphinx caterpillar and adult

 

Columbia County, like in much of our region, has a deer problem. Whether in forests, meadows, or un-fenced gardens, it is clear that nearly everything in their reach is being browsed. This browsing is another threat to Columbia County Sphinx Moths, specifically to the Hemaris species, including the Snowberry Clearwing and the Hummingbird Clearwing. Although we see the diurnal adult clearwing moths nectaring at flowers, their caterpillars are dependent upon various woody and herbaceous plants of forests and meadows, including Viburnum, Honeysuckle (possibly native and non-native varieties), Hawthorn, and Dogbane. These are all relatively small plants. Because their larval host plants are generally low and easily reached by deer, the Hemaris larvae are more affected by these herbivores than larvae that rely on leaves of trees or taller shrubs.

When a larva’s food plant is stunted or killed by widespread herbivory, or anything for that matter, it reduces or removes a vital resource of that species, preventing the completion their life cycle. A Lepidopteran cannot successfully reproduce without access to its larval food plant, which then must sustain the caterpillar until metamorphosis; only as adults can they reproduce. It is hard to say the degree to which deer herbivory in Columbia County, which does seem excessive in certain habitats, is affecting our resident clearwing Sphinx Moths or other Lepidopterans that rely on low plants frequently browsed by deer. NatureServe, a network that assesses the conservation needs of western hemisphere species, notes that deer herbivory when in excess is a serious threat to both the Hummingbird and Snowberry Clearwing. The organization reports other pervasive threats, including herbicides and invasive plants that reduce the abundance of Viburnums and other larvae food plants relied on by these species.

 

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A Hummingbird Clearwing unfurls its proboscis for feeding

 

If you are interested in learning more about Columbia County moths, visit our webpage for a photographic list that we are frequently adding to. We would greatly appreciate hearing from any readers in our region who would like to share historical observations or collections (not for our keeping of course) of moths or butterflies from our area. Additionally, if you have any current observations that you’d like to share, or any questions, please contact me (dacipkowski@gmail.com). Below, I have listed some moth field guides for our region that are relatively inexpensive and are great resources for species identification and further reading.

 

 

Works Consulted

Ardetti, J., Elliott, J., Kitching, I.J. & Wasserthal, L.T. (2012). ‘Good Heavens what insect can suck it’ – Charles Darwin, Angraecum sesquipedale and Xanthopan morganii praedicta. Botanical Journal of the Linnean Society. 169 403-42.

New York Department of Environmental Conservation. New York State Ash (Fraxinus spp.) Distribution: Percentage of Ash per Basal Area per County [Map]. <http://www.dec.ny.gov/animals/71542.html&gt; (accessed August 13, 2016).

Himmelman, J. (2002). Discovering Moths: Nighttime Jewels in Your Own Backyard. Camden: Down East Books.

Kawahara, A.Y., Mignault, A.A., Regier, J.C., Kitching, I.J., Mitter, C. (2009). Phylogeny and Biogeography of Hawkmoths (Lepidoptera: Sphingidae): Evidence from Five Nuclear Genes. PloS One,. 4(5), e5719.

Schweitzer, D.F., Minno, M.C., Wagner, D.L. (2011). Rare, Declining, and Poorly Known Butterflies and Moths (Lepidoptera) of Forests and Woodlands in the Eastern United States. U.S. Forest Service, Forest Health Technology Enterprise Team, FHTET-2011-01.

Vispo, C.R. (2014). The Nature of the Place. Hillsdale: Adonis Press.

Wagner, D.L. (2005). Caterpillars of Eastern North America. Princeton: Princeton University Press.

Wagner, D.L. (2012). Moth Decline in Northeastern United States. News of the Lepidopterist’s Society, 54(2), 52-56.

 

Moth and Caterpillar Guide Books for Our Region

 

Peterson Field Guide to Moths of Northeastern North America

This guide book by David Beadle and Seabrooke Leckie is an excellent resource for getting to know moths. It includes additional information for each species, including range, if it’s common or uncommon, and the larval food plant.

Caterpillars of Eastern North American

David L. Wagner’s caterpillar guide is an essential tool if you’re hoping to identify caterpillars you see in our region. If you know what kind of plant the caterpillar was on, this guide’s food plant index makes identification very easy.

 

Additional Online Resources

www.hvfarmscape.org/moths

www.bugguide.net

www.mothphotographersgroup.msstate.edu

www.butterfliesandmoths.org

www.natureserve.org

 

 

 
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Posted by on August 29, 2016 in Uncategorized

 

The Merry Dancers

Church Aurora

Aurora Borealis (1865) by Frederic Church. While Church apparently based this image in part on the notes and sketches from an Arctic-exploring friend, he likely witnessed the aurora personally at times as well, perhaps even from the land around Olana. While a straightforward landscape depiction at one level, this painting is also believed to present an allegory for the culmination of the Civil War. Courtesy Wikipedia and Smithsonian Institution. Image in the public domain (https://en.wikipedia.org/wiki/Aurora_Borealis_%28painting%29#cite_note-3).

 

PLEASE NOTE: There are three different ways that you can read this blog. First, read ye olde paper copy – go out and buy the Columbia Paper, and read it as our end-of-year “Perspectives on Place” contribution; second, you can read the digital narrative below and ignore the footnotes, thereby getting the gist of it all, and saving yourself the mind-twisting details (it is a holiday after all!); lastly, if you want to be hard core and take advantage of the ‘added content’, then explore the links to the footnotes – they’ll take you a level deeper into understanding our shifting aurora, watch out for the geomagnetical quicksand. However you do it, we hope you enjoy it!

*****

 

On February 19th, 1831, at around 8:30pm, somebody, possibly Principal J.W. Fairchild, stood looking at the night sky from near the Hudson Academy atop Prospect Hill. A half moon hung in the dark. Notebook in hand, our observer was aurora watching, and tonight he was not to be disappointed:Brilliant…in the west and south west, shooting up in spangles towards the zenith, very much like the process of crystallization beneath the solar microscope. These consistently faded, and were succeeded by others in different lines, exhibiting at times most of the colors of the rainbow. About half-past 9, similar appearances were seen in the east and south east, meeting those mentioned at the centre above, and forming an illuminated dome of spars and spangles, the most brilliant and beautiful ever beheld.”1

On that same night, others were also peering upwards. Near Kinderhook, the aurora (aka Northern Lights) was uncommonly beautiful streaks of light. At Albany, columns were observed shooting up to the zenith from the whole northern hemisphere”. In New York City, the aurora began to be visible around 9PM, and was “peculiarly interesting… Some of the eastern coruscations were at times transiently curved, as though their middle parts were driven eastward by the impulse of the westerly breeze that was blowing at the time… A luminous band…passed near the moon, around which was one of the large haloes.” Sky watchers in Otsego, St. Lawrence, Oneida, Franklin, Herkimer, Westchester, and Kings Counties also logged awe-inspiring displays on that evening.

While particularly brilliant, this was no one-off: around the State, throughout the calendar, and across the years such night logs accumulated. These observations were not the incidental sightings of several people who happened to be out for a night-time ramble, they were mostly the duly-reported annotations of participants in one of the Country’s earliest citizen-science efforts: the network of New York State academies, which Anna described in an October Columbia Paper article. These men (and they were almost all men) had been enlisted by the Regents to gather observations on the working of the weather and other celestial processes. While not institutions of the Regents, the Regents provided limited funding for the payment of teachers and other necessities, and the academies filed annual reports justifying and describing their efforts. Beginning in 1827, they were also asked to brave the night-time chill in order to note auroral activity.2

At that time, scientists were only just beginning to turn an analytical eye to the weather, although the revolutionary idea of weather forecasting was still a couple of decades away. What the so-called Scientific Revolution had so far brought to meteorology was not its understanding, but rather the conviction that it could be understood. For generations, people had read portents into celestial events, deriving omens good or bad from the likes of haloes, meteors, eclipses, and auroras. Now ‘science’ was taking its turn. Observers were observing and patterns being sought. Who knew what mysterious threads might link aurora, magnetism, electricity, and weather? For example, based on observations made two months later to the day, a then-little-known teacher at the Albany Academy drafted a short note entitled “On a disturbance of the Earth’s magnetism, in connection with the appearance of an Aurora Borealis, as observed at Albany, April 19th, 1831”. The author was Joseph Henry and, in 1849, he was appointed the first Secretary of the nation’s premier national scientific institution – the Smithsonian, whence he spearheaded meteorological studies, including the creation of the Country’s first weather maps.3

In good scientific form, the Regents tried to standardize the work of their collaborating observers so that the reports would be more comparable across geography and time. In 1833, they published aurora observation instructions assembled by the illustrious British Society for the Advancement of Science: during a one-hour observation period set to begin at 10PM, various characteristics were to be noted such as opacity, breadth, velocity relative to the stars, lateral motion, “defects in symmetry” and elevation with the aid of a theodolite. However, despite such analytical instructions, the aurora continued to simply enthrall. On January 14th, 1837, for example, a Kinderhook observer described the show asBrilliant, fantastic and very changeable; arcs, radiations, flashes and lurid banks On the third of September 1839, an Albany viewer noted Splendid; the entire heavens lighted up with long massy rays of a rich silver hue, radiating from the zenith, and forming a dome of magnificent proportions. Deep crimson mass in east and west alternately, which formed a striking contrast with the long lines of white light with which it at times mingled… Light so strong at times it cast shadows.” On 18 November 1848, an observer in New York City reported, The Merry Dancers very numerous.” 4

Each of the Regents reports was filled with such notes, and a 19th-century compiler estimated that, at one academy or another, the aurora were noted on about 50 nights per year. While the Regents may have struggled to derive standardized information, it’s clear that many had the opportunity to wax poetic about these light shows. Fast forward to the present, and how many of you have seen aurora from your backyards? Aside from any mystery about their origins and interconnections with other terrestrial and celestial phenomena (connections which are, by the way, still debated), one of the questions that taps most persistently at the skull of a modern reader of these accounts is, Where are the aurora today? The answer to that question tells us something about the aurora and perhaps something about ourselves.5

One of the explanations for why we see fewer auroras today is, simply, that there are fewer. This is because the Sun is fickle and the poles have wanderlust. The current scientific explanation for the aurora is that a flow of protons and electrons emanating from the Sun as the solar wind interacts with the Earth’s atmosphere, exciting atmospheric atoms which release light as they subsequently calm down. Because of the interactions with the Earth’s magnetism, an auroral halo forms in a roughly 350-mile wide band about 10-20° from magnetic north (or south). The stronger the ‘hose’ of the solar wind, the brighter is that halo and the farther from the poles the auroras are visible. While some of the high ‘floods’ of solar wind are caused by unpredictable solar flares, others are associated with turbulence on the Sun’s surface which, in turn, can be indexed by counting sun spots, those dark blemishes visible on the Sun’s skin. More sun spots will, in general, mean more aurora. There is a continuous record of sun spot abundance going back into the 1700s, and so we have a way of numerically comparing then and now in terms of one force behind the aurora. Inspection of those records reveals a roughly eleven-year cycle in sunspots and shows that we are indeed on the waning arm of one of the weakest recorded sunspot cycles.6

On top of this, we are getting farther from the magnetic North Pole. The magnetic North Pole and the rotational North Pole – the one heralded by the North Star – are not the same. Indeed, the point towards which your compass directs you has diverged from the rotational North Pole for all of its recorded history. Furthermore, the magnetic North Pole, to the chagrin of navigators, wanders. Today, it is moving towards Siberia at around 35 miles per year. In 1831, the year it was first pin-pointed, the magnetic pole lay at about 70° N, 96° W (a location in northern Canada some 1400 miles from the rotational North Pole and 2100 miles from us); today it is found at roughly 86° N, 159° W (a spot in the Arctic Ocean about 250 miles from the rotational North Pole and 3200 miles from us). The auroral halo has moved with it. Picture a classical monk with his tonsure of hair around a bald pate. With a good barber, the ring of hair will perfectly encircle the top of his head, and a fly sitting on either ear gets a roughly equal view of the furry higher reaches. Now suppose that, after a few glasses of wine, the barber is a bit off center – he keeps the radius of the hair ring constant, but tilts its center point to the left. The fly on the monk’s left ear may then be brushing the hairs from its eyes, while the fly on the right ear may be convinced the monk is now bald. If we assume the ring of hair is the aurora, the monk’s head is the globe, and we observers are flies, then we were the left-ear fly in the 19th century but are now heading towards being the right-ear fly. The auroral halo is receding from our view.7

These celestial and geophysical processes probably account for much of the auroral drought at our latitudes, but we ourselves may also be contributing. Foremost amongst our own contributions is probably light pollution, the erasing of the nighttime sky by our ever-more powerful lights. In the Academy records, for example, Erasmus Hall, located near Prospect Park in what is today Brooklyn, provides some of the most vivid descriptions of the Northern Lights. One need only compare the candlepower of a mid-19th century gas street lamp (ca. 13 candlepower) with those of a modern street lamp (potentially measured in the 1000s) to understand that the neighborhood of Erasmus Hall was surely a darker place during that era. Such is true not only of city locations but also of more rural spots, where the light auras of nearby villages or cities, or of the commercial or residential cluster down the road tinge the nighttime sky and so can mask faint auroral glows.8

Finally, while we can pin some of the blame for the apparent rarity of modern aurora on sun cycles, drifting poles, and light pollution, perhaps we are also short in the wonder that fuels observation. Those academicians, stamping their feet, clutching their pencils, and, no doubt, pulled by the tasks of the day ahead or behind, weren’t just out to see a show, they were out to discover. They believed that through patient, coordinated observations, perhaps with compass (to detect auroral-induced magnetic variation) and theodolite in hand, they could start unraveling the aurora’s secrets, revealing mysteries which had puzzled generations. Curiosity and the idea that new knowledge could be derived from the observations of the ‘common person’ was heady stuff and likely a potent spur for getting up from beside the fire. Imagine looking at the night sky and seeing more questions than answers; and imagine believing that some of those answers might be at your own finger tips. One of the greatest challenges to learning today is, I think, the perception that we know it all. We don’t, but sometimes the enticing corners of unknown which can be illuminated by our own senses get buried beneath a dulling hubris.

It’s unlikely that many of us who stay in the County during this upcoming days will see the aurora, and yet who cannot wish that their holidays might sparkle just a bit more given a visit from the Merry Dancers. We wish you all such a visit and, more than that, we hope that as you travel through the natural world in 2016, you have the health and peace of mind to really wonder.9

This image of the Aurora was created by Étienne Léopold Trouvelot, a Frenchman who worked in Boston from about 1852 to 1882. The subtitle states "As observed March 1, 1872, at 9h. 25m. P.M.", presumably from near Boston. An accomplished astronomical artist, Trouvet is best known today as the man who introduced Gypsy Moth into Massachusetts. Reportedly, he alerted others to the potential problem, but none took him seriously.

This image of the Aurora was created by Étienne Léopold Trouvelot, a Frenchman who lived in Boston from about 1852 to 1882. The subtitle states “As observed March 1, 1872, at 9h. 25m. P.M.”, presumably from near Boston. An accomplished astronomical artist, Trouvelot is best known today as the man who introduced the Gypsy Moth into Massachusetts. Reportedly, he alerted others to the potential problem, but none took him seriously. Image courtesy of Wikimedia and the New York Public Library.

 

Footnotes

1) ^ Each year the academies submitted their reports, including aurora sightings, to the Regents. These reports were compiled and published in the Annual Report of the Regents. Periodically, these annual reports were gathered together and published in a multi-year volume. The first such volume was published in 1855; and the second in 1872.

There are many beautiful auroral videos on line; here are two of my favorites, feel free to suggest your own: Ole Salomonsen’s Polar Spirits, much of which may be accelerated time-lapse photography, and these two (by Garðar Ólafsson and Ronn Murray) which are in real time and so perhaps give you a better feel for what the 19th century observers were probably seeing. This space-station footage shows a unique, if somewhat ‘distant’, view of the Aurora.

2) ^ For more on the network of academies, see our web page on this project.

3) ^ The Smithsonian has a web page profiling Thomas Henry and his role in early meteorological studies. Henry’s early article on magnetism is available here. While it only touches upon developments in the US, Peter Moore’s captivating book on the development of 19th century meteorology, The Weather Experiment, is a fine read that provides relevant background on the state of meteorological thinking at this time. For an example of contemporary pattern searching using these records, see Joslin’s Meteorological Observations and Essays (1836).

4) ^ Eager to try Aurora observation yourself? Check out the British Association for the Advancement of Science’s Instructions for Observers of Aurora Borealis as published in the 1834 Annual Report of the Regents. Despite its jovial, spontaneous sound, “Merry Dancers” was actually a repeated descriptive term in the Aurora accounts, and I’m not sure if it referred to all Aurora or to a particular class of Aurora. One hint on contemporary usage comes from the 1838 Annual Report, in which a Mr. Haskins, a Buffalo-based observer states,”All these [auroral streamers] rose, faded, and were renewed again and again, with great rapidity; but they did not exhibit any of that tremulous motion sometimes denominated Merry Dancers” [italics in original]. As this blog describes, the term may have originated in the northern isles of the UK, although it’s not hard to believe that it popped up more than once.

5) ^ For papers describing apparent links between sun activity (as reflected in aurora) and concurrent climate, see this paper (summarized here) by two NASA scientists linking water levels in the Nile with northern European auroral observations between 622 and 1470 AD. Another paper, by a researcher at Duke University, compares climate cycles and auroral cycles.

6) ^ For background on the aurora and their connection with solar storms, see this easy-to-understand video. It gives an overview of the connection between solar storms, sunspots, and the Earth’s magnetic field. As is often the case, Wikipedia contributors do a nice job, its pages on sunspot cycles and its table of historical cycles provide some textbook-style background; either source will provide you with a sketch of current and bygone sunspot cycles.

For those of you leery of links (or lazy), here are two graphs showing sunspot cycles:

https://i2.wp.com/www.nasa.gov/images/content/352130main_ssn_yearly_lg.jpg

Sunspot cycles since about 1600. The Maunder Minimum was an intriguing late 17th century sunspot lull; Wikipedia offers a good summary of it. In this image 1928 is marked because, when this graph was made in 2009, scientists believed it would be similar to the upcoming cycle. (Where they right? See below.) Notice how sunspot activity in the mid-1800s seem relatively high, although there was also a mid-20th century peak. From http://www.nasa.gov/topics/solarsystem/features/solarcycle24_prt.htm;

 

The latest sunspot number progression plot

The scientists who predicted that the most recent cycle would peak at levels similar to the 1928 peak were not far off; this cycle seemed to peak with a sunspot index of about 75 sunspots. From http://www.swpc.noaa.gov/products/solar-cycle-progression.

 

7) ^ Before getting into the deep and mucky intricacies of the priest’s wandering tonsure (https://upload.wikimedia.org/wikipedia/commons/e/e2/Tonsure_fx_tr.png), there’s a useful number to become familiar with: the Kp index. This index is, so far as I can understand, a number representing on the scale of 0 (very low) to 9 (very high) the current strength of solar wind being experienced by the Earth. Apparently the “p” stands for planetary and the “K” stands for the German word Kennziffer which means, ta-da, ‘characteristic number’. There, doesn’t that help?!  Basically, it seems to be a measure of how much the lines of magnetic force around the Earth are deviating from orientations typical of calm solar weather. Think of the surface of a pond: when there’s no wind, that surface is perfectly flat, however, as the wind builds, so too does the angle assumed by the waves of water. That’s not a perfect analogy, but as the solar wind increases, the magnetic lines are pushed further from the norm, and so higher Kp, means higher solar wind energy.

The reason Kp is so useful to us is that, because it is directly related to solar wind energy, it is also, more or less, directly related to aurora strength and, hence, the chance of seeing the aurora at any particular place on Earth. Maps such as this indicate the Kp value at which aurora might be visible at a given latitude. Using that map, one can predict that, at our latitude, aurora would not be visible unless Kp reached about 7 or higher, quite a strong solar storm. For our purposes (this doesn’t hold at the highest latitudes), the farther one is from the magnetic north or south pole, the higher the Kp needed to view an aurora. But, you may ask, how the heck am I supposed to know the current Kp values, it’s not as if they are regularly given on the six o’clock weather? Luckily for aurora lovers, there are regular forecasts. The NOAA space weather program, for example, gives the latest Kp index on this page (for the everything-and-the-kitchen-sink version of these data, see this page). As I write this, the Kp index is around 3, and there’s no point in my running outside to scan for aurora.

How kind, you may think, for the government to cater to aurora lovers. Their motives are more practical: geomagnetic storms not only cause aurora, but can also cause radio interference and, at high levels, badly damage power grids. During the greatest recorded solar storm in 1859, not only were there terrific aurora, but some telegraph operators were able to communicate with each other relying only on the solar electrical energy gathered by their transmission lines. Other operators were less fortunate and received bad shocks and/or had their equipment disabled by the storm. For more on that 1859 solar ‘hurricane’, you can read this account.

OK, so the last part of our puzzle is this: if we know that the Kp value (i.e., the intensity of solar storm) needed in order to make aurora visible increases with distance from the magnetic north pole, and we know that the magnetic north pole has wandered away from us over the last 200 years or so (e.g., see this map or, with bells and whistles, here), then what Kp value was needed in order for there to be visible aurora at our latitude in 1831, when the magnetic north pole was first directly determined, and how much more likely did that make a visible aurora for, say, an observer in Kinderhook?

Answering that will involve a series of ‘back-of-the-envelope’ calculations whose crudity would probably make a good space scientist shudder. (Actually, a couple of them gave me input on this, but my mistakes remain my own.)

Here are the basics:

In 1831, when Ross first pinpointed its exact location, the magnetic North Pole was found at about 70.09°N, 96.77°W. Today, best estimates put it at around 86.3°N, 160°W. These locations are, respectively, about 2095 and 3230 miles from our present location in Hillsdale, NY. In other words, relative to the magnetic pole, we are now about 1135 miles farther south than we were in 1831.

However, if one gets down to the nitty-gritty, as I did with the help of those kind folks at USGS and NOAA, it’s not, strictly speaking, just the magnetic pole’s location that determines the likelihood of us seeing aurora. It’s all a bit more complicated but can be reduced to a number called “corrected geomagnetic latitude”; a short-hand for determining how far north we are relative to the geomagnetic (rather than geographic) North Pole,  NASA has a handy-dandy web page for calculating one’s corrected geomagnetic latitude for various years.

Using that tool, in turns out that our modern “corrected geomagnetic latitude” is about 51°N, whereas it was about 55.3°N in 1900 (the earliest date this tool accepts and, given how little the poles wandered between 1831 and 1900, probably not too far from the 1830s-1840s value). In other words, we were, from an auroral perspective, about 5° (or 350 miles) further north back then.

If we return to that map of the Kp’s needed in order to have visible aurora, we can make the following hypothetical modification,

Kp map

Our effective latitude, relative to the geomagnetical North Pole, in the 1800s vs. today. We were, in terms of aurora viewing, about 350 miles further north.

Be careful to interpret this map correctly. Relative to the geographic North Pole, we basically didn’t move over this period, so this does not say we were  experiencing southern-Canadian seasons in the 1800s. However, relative to the geomagnetic fields, our relocation has been more dramatic. Following this logic and using the above map, in the 1800s we were probably experiencing aurora skies like those in Minneapolis or southern Canada today. In other words, we saw aurora at a Kp of around 5, whereas today we need a Kp of 7 or higher.

Continuing on this vein, how much more likely were local residents to see aurora in the 1800s vs. 2015? To answer that we have to ask how frequent various Kp values are – in other words, how likely is it for the Earth to be buffeted by a Kp7 solar wallop vs a stiff Kp5 gale? Luckily for us, two authors named Zawalick and Cage wrote just such a paper (in 1971 in volume 76 of the Journal of Geophysical Research, pages 7009-7012) for the period 1932-1970. If we use their Kp frequency table as a reasonably accurate reflection of the likelihood of Kp reaching various levels, then we can conclude that Kp levels reach 5 about 8% of the time, whereas they reach 7 about 1% of the time. In other words, based on this calculation, visible aurora were about 8 times more likely in the 19th century than today. Of course, these calculations are frighteningly crude and, as the above narrative suggests, many other factors also influence the abundance of visible aurora, including sun spots, light pollution, weather, etc. However, it seems likely that wandering magnetic poles may have played a part in the 19th century abundance of aurora reports.

Indeed, some evidence in the historical accounts suggests, we may have been, geomagnetically speaking, even further north during 1830-1850: the summary of aurora records for that period states that they were seen in New York on about 50 nights per year; that would be about 14% of the nights. If that’s an accurate estimate (and it may not be), it would suggest that aurora were visible at Kp values of between 4 and 5, suggesting that our “corrected geomagnetic latitude” was perhaps closer to 57°N. Got that?

8) ^ For more on the history of NYC lighting, see this paper.

9) ^ Finally, those of you who have read this far deserve a treat, one more image (below) and this, my favorite aurora forecast web page. Enjoy, happy aurora hunting and please let us know what you see!

 

An engraving perhaps from New York State, from page 271 of American Progress or, The Great Events of the Greatest Century, published in 1890 by Richard Devens and available on-line through archive.org.

An engraving, perhaps from New York State, from page 271 of the humbly titled American Progress or, The Great Events of the Greatest Century, published in 1890 by Richard Devens and available on-line through archive.org. See pages 269-275 of that book for an exciting historical narrative of the November 1837 aurora.

 

A big thanks to Josh Rigler of USGS and Rob Steenburgh of NOAA for helping me piece this together.

 

 

 
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Posted by on December 24, 2015 in Uncategorized

 

Highlights from an Ecology Walk through the Oak-Heath Barrens of Taconic SP in Copake, NY

The Oak-Heath Barrens around Sunset Rock in Taconic State Park in Copake, NY were the destination of an Ecology Walk guided by the Farmscape Ecology Program on June 7, 2015. Here, we share some of the highlights from that walk and provide information that will help others explore this unique and beautiful habitat on their own.

Oak Heath Barren near Sunset Rock in Taconic SP, Copake NY

Oak-Heath Barren near Sunset Rock in Taconic SP, Copake NY

The Oak-Heath Barrens are characterized by low, shrubby vegetation surrounding occasional rocky outcrops. There is no tree canopy, although scattered Red Oak, White Oak, Red Maple, Pitch Pine, Sassafras, Shadbush, and Grey Birch do reach above the shrub layer.

Trail to Sunset Rock through Oak Heath Barren habitat

Trail to Sunset Rock through Oak-Heath Barren habitat

This habitat is called Oak-Heath Barrens for a reason: oaks and members of the heath family (Ericaceae; marked with * in the remainder of this paragraph), feature very prominently. The tallest shrubs, growing above the height of a person, are Scrub Oak, Mountain Laurel*, and Mountain Azalea*, mixed with stunted Red and White Oak. The hip-high shrub layer consists mostly of Black Huckleberry*, Chokeberry, and an occasional Deerberry*. Below that, three species of Lowbush Blueberries (Early*, Late*, and Velvetleaf* Blueberry), Wintergreen*, Trailing Arbutus*, and Bearberry* provide a fairly dense ground cover. For more details, you might want to look into the excellent community guide for Pitch Pine-Oak-Heath Rocky Summit compiled by the New York Natural Heritage Program.

View west from Sunset Rock across the Harlem Valley of Columbia County; the  Catskills are barely visible on the horizon

View west from Sunset Rock across the Harlem Valley of Columbia County; the Catskills are barely visible on the horizon.

In Columbia County, we find Oak-Heath Barrens almost exclusively located along the Taconic Ridge which extends N-S along the eastern border. Some of the most breath-taking views of the County are from peaks and lookouts on that ridge. However, much of the ridge remains forested and the lookouts are a rare treat to be reached only by walking through the dense, low forest that covers most of the ridge. Fortunately, a significant portion of the Taconic Ridge is protected from development.

Participants in the Ecology Walk to Sunset Rock on June 7, 2015

Participants in the Ecology Walk to Sunset Rock on June 7, 2015

There are several ways to access Sunset Rock and the surrounding Oak-Heath Barrens. Our group took the easiest way: drive up Sunset Rock Road in Copake, park at one of several small parking areas near the crest of the road, and follow one of the two foot paths which will merge into the South Taconic Trail continuing south along the ridge. Alternatively, one can park at the Taconic State Park headquarters in Copake Falls and hike up the trail behind the camp ground. Most adventurous, but also most interesting, is the Cedar Brook Trail, which starts just across the road from the main parking lot for Bash Bish Falls.

Three hiking trails leading to Sunset Rock

Three hiking trails leading to Sunset Rock

Above map is just a rough sketch of the approximate route of the trails. An excellent hiking map for the South Taconic Trails (which includes other trail options in Taconic State Park) can be purchased for $ 6.95 from the New Jersey – New York Trail Conference.

However you find your way, you have to be prepared to walk through some forested areas before reaching the barrens and their occasional lookouts.

Oak Heath Barrens south of Sunset Rock

Oak Heath Barrens south of Sunset Rock

South of Sunset Rock is Cedar Mountain, whose south slope can be reached by bush-whacking and provides a breath-taking view of Mt. Alander, located south of Bash Bish Gorge.

View south from Cedar Mountain, south of Sunset Rock

View south from Cedar Mountain, which is located south of Sunset Rock

The warm and dry southern slopes along the Taconic Ridge tend to be covered by a low and open Oak Woodland.

Oak Woodland on the south slope of Cedar Mountain

Oak Woodland on the south slope of Cedar Mountain

However, during our walk, we only explored the trail between Sunset Rock Road and Sunset Rock. It was lined with Pink Lady’s Slippers in full bloom. Although this is our most common native orchid in the County, it only occurs in a few places, mostly in the eastern part. Orchids have a delicate symbiosis with soil fungi. That is why they don’t disperse easily and tend not to survive attempts at transplanting. Please enjoy them in their natural environment and leave them undisturbed for others to enjoy!

Pink Lady's Slipper (Cypripedium acaule), one of our most common native orchids

Pink Lady’s Slipper (Cypripedium acaule), one of our most common native orchids

Pink Lady's Slipper (Cypripedium acaule)

Pink Lady’s Slipper (Cypripedium acaule)

Occasionally, we spied a Mountain Azalea (or Pinkster)* bush that still had a few blossoms. Their peak bloom is usually in late May.

Pinkster, Pinxter, Rosebud Azalea, Mountain Azalea are all common names for this beautiful Rhododendron prinophyllum

Pinkster, Pinxter, Rosebud Azalea, Mountain Azalea are all common names for this beautiful Rhododendron prinophyllum

In Columbia County, we have two species of pink-flowering Azaleas. The Azaleas around Sunset Rock are Rhododendron prinophyllum, recognizable by a combination of characters: gland-tipped, sticky hairs on the flower stalk; corolla lobes approx. as long as the corolla tube; style not much longer than the stamens; leaves quite hairy below; and, finally, the heavenly perfume of the flowers!

Pinkster (Rhododendron prinophyllum)

Pinkster (Rhododendron prinophyllum)

Another pink beauty, flowering 3-4 weeks after the Azalea, is the Mountain Laurel, which was just starting to open some of its spectacular flowers. We expect them to be in full bloom the third week of June.

Mountain Laurel (Kalmia latifolia)

Mountain Laurel (Kalmia latifolia)

Not as common, but beautiful in their delicate way are the open bell-shaped flowers of Deer- or Squawberry, a type of blueberry that grows relatively tall and produces edible, but dryish and not very tasty fruits.

Deerberry or Squawberry (Vaccinium stamineum)

Deerberry or Squawberry (Vaccinium stamineum)

Along the path in to Sunset Rock, Conrad caught this Lilypad Clubtail dragonfly.

Lilypad Clubtail (Arigomphus furcifer) dragonfly

Lilypad Clubtail (Arigomphus furcifer) dragonfly

Reading up on this species, we learned that it lives around ponds and lakes with lilypads or other floating vegetation. What was it doing up on the hill with no water in sight? Dragonflies, like some other insects, are known to “hilltop”, i.e., fly up to the top of a hill and hover around, often in swarms. It has been suggested that this is part of their strategy to find mates (e.g., ‘let’s rendezvous at the top of the hill’) and might be a behavior that makes it easier for individuals of a relatively scarce species to find each other….

Back to plants:

Always growing right next to bare rock, we found the Three-toothed Cinquefoil, a plant which in Columbia County exclusively occurs in open areas along the Taconic Ridge.

Three-toothed Cinquefoil (Sibbaldiopsis tridentata)

Three-toothed Cinquefoil (Sibbaldiopsis tridentata)

Another plant which we regularly find on the Taconic Ridge, but rarely see elsewhere in the County, is the semi-parasitic Bastard Toadflax. Its roots tap into the roots of other plants and steal nutrients. It has been shown to parasitize a wide range of species (more than 200!) including blueberries, asters, birches and maples, as well as grasses. However, it has green leaves and is perfectly able to photosynthesize.

Bastard Toad-flax (Comandra umbellata)

Bastard Toad-flax (Comandra umbellata)

A very exciting find was this little plant with a single whorl of parallel-veined leaves.

Large Whorled Pogonia (Isotria verticillata) orchid

Large Whorled Pogonia (Isotria verticillata) orchid

When I first saw it, I thought is was a young individual of Indian Cucumber Root (pictured below in its older, two-whorled stage), which can currently be seen in great numbers along the road leading up Harvey Mountain.

Indian Cucumber-root (Medeola virginiana) seen on Harvey Mountain on June 7, 2015

A two-tiered Indian Cucumber-root (Medeola virginiana) seen on Harvey Mountain on June 7, 2015

Indian Cucumber Root has the same parallel-veined leaves as the plant we observed on the trail to Sunset Rock, but it produces small, very symmetrical, three-parted flowers that dangle from the second whorl of leaves and place it squarely in the lily family.

Flower of Indian Cucumber-root (Medeola virginiana) seen on Harvey Mountain

Flower of Indian Cucumber-root (Medeola virginiana) seen on Harvey Mountain

The whorled-leaf plant we observed on the way to Sunset Rock, would have looked similar to the one pictured below a few weeks ago, which is a Large Whorled Pogonia. If you scroll back up, you can actually see the remains of the flower shriveled up on top of the leaves. The Large Whorled Pogonia is a very rare orchid in the region and had not been documented in Columbia County for more than a century. It was recently discovered and brought to our attention by David Lewis and Ellen Winner. Last year, we located the small colony near Sunset Rock, and now know that this species occurs at a few locations in Taconic State Park, but have not seen it anywhere else in the County.

Large Whorled Pogonia (Isotria verticillata) orchid in flower in late May 2015 at another location in Taconic SP (photo by David Lewis)

Large Whorled Pogonia (Isotria verticillata) orchid in flower in late May 2015 at another location in Taconic SP (photo by David Lewis)

Last year, one of the plants on the side of the trail to Sunset Rock was starting to develop its seed capsule.

Large Whorled Pogonia (Isotria verticillata) orchid with its seed capsule developing (photo by David Lewis taken in June 2014 along the Taconic Crest Trail)

Large Whorled Pogonia (Isotria verticillata) orchid with its seed capsule developing (photo by David Lewis taken in June 2014 along the Taconic Crest Trail)

Should you ever come across plants of this species anywhere else in Columbia County, we would love to hear where else it grows! According to my orchid book, Large Whorled Pogonia tend to occur in the same places as Pink Lady’s Slippers…

Please share your find with claudia@hawthornevalleyfarm.org and attach a picture.

However, be aware that there is another plant with a similar single whorl of leaves, the Starflower. A careful examination of the vein patterns in the leaves can avoid confusion. Starflower has pinnate veins, which means there is a main vein that runs along the middle of the leaf and secondary veins which emerge from the main vein in a feather-like pattern. Large Whorled Pogonia has several main veins running parallel from leaf base to tip, like other orchids (and lilies and grasses, etc.).

And do keep in mind its very confusing look-alike, Indian Cucumber-root! Whenever you see a colony of whorled-leaf plants where some have a single-tiered whorl and some have a double tier, then you are most likely looking at Indian Cucumber-root – Whorled Pogonia is never double-tiered.

A rough outline of the three trails that lead to Sunset Rock

Starflower (Trientalis borealis ) has a whorl of somewhat unequal-sized leaves with pinnate venation

Probably the most puzzling observation we made during our walk was that of a Flower Gall on Black Huckleberry. Note the perfectly normal Huckleberry flowers in the top left corner of the image.

Flower Gall on Black Huckleberry (Gaylussacia baccata) probably caused by the fungus Exobasidium vaccinii, also known as the

Flower Gall on Black Huckleberry (Gaylussacia baccata) probably caused by the fungus Exobasidium vaccinii, also known as the “Azalea Leaf & Flower Gall”

None of the walk participants had ever seen such a thing and we could only guess that something quite abnormal was going on here… Upon closer examination, the strange growth really did look like a blown-up flower, complete with 5 sepals, a 5-lobed urn-shaped corolla, 10 stamens encircling the central pistil. We made sure to document this phenomenon with a series of photos and, back home, researched the internet for ideas. We concluded that these flower galls were probably caused by the fungus Exobasidium vaccinii, also known as the “Azalea Leaf & Flower Gall”. However, we are no fungi experts and if somebody has a different insight, we’d love to hear about it!

Flower Gall on Black Huckleberry (Gaylussacia baccata)

Flower Gall on Black Huckleberry (Gaylussacia baccata)

The most curious thing is that, supposedly, the same fungus is the cause of the huge but irregularly shaped galls commonly found on Pinkster…

Galls on Pinkster (Rhododendron prinophyllum) probably caused by the fungus Exobasidium vaccinii or

Galls on Pinkster (Rhododendron prinophyllum) probably caused by the fungus Exobasidium vaccinii or “Azalea Leaf & Flower Gall”

Finally, we came across several small dead or dying trees, surrounded by a ring of fresh root shoots. They were the ghosts of once stately American Chestnut trees which used to be an important component of many forests around here. In the early 20th century, Chestnut Blight (Cryphonectria parasitica), another fungal disease, was accidentally introduced to this continent and has basically wiped out large, seed-bearing Chestnut trees. The roots from trees that died a century ago persist in the ground and keep sprouting hopeful new shoots, which tend to grow into small trees, but usually succumb to the blight before they can flower and set seed. They then repeat the cycle of hopeful new shoots once more…

American Chestnut (Castanea americana) root shoots

American Chestnut (Castanea americana) root shoots

Conrad is wondering, what this significant change of a former common canopy tree to an occasional shrub in the understory might have meant for the native insect life that had evolved to live on American Chestnut. We can imagine that the lack of chestnuts in the fall meant a loss to Blue Jays, Black Bear, Turkey, Deer, squirrels and mice. But who else might be missing the leaves or plant juices of American Chestnut? How many little creatures who depended on this tree have been significantly reduced in numbers or gone extinct due to the Chestnut Blight? We may never know…

Leafhopper (?) nymphs on American Chestnut

Leafhopper (?) nymphs on American Chestnut

Are the insects we now find feeding on American Chestnut sap or leaves specialists dependent on the remaining surviving Chestnut plants, or are they generalists who feed on a variety of trees and just so happened to be feeding on a Chestnut???

Caterpillar on American Chestnut

Caterpillar on American Chestnut

Such are the little ponderings we bring home from our walks.

But we were happy to see the Pink Lady’s Slippers holding their ground along the Taconic Ridge. And we hope that many more generations of nature lovers will be able to enjoy them along the South Taconic Trail.

Pink Lady's Slipper (Cypripedium acaule)

Pink Lady’s Slipper (Cypripedium acaule)

 
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Posted by on June 14, 2015 in Nature

 

‘When did Swallows First Arrive to Kinderhook, NY in 1835?’: Why You Might Care & Why You Can Now Know.

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from The New England Farmer by Samuel Deane, 1822.

Weather forecasting and climate study have changed not only how we plan our days but also, I think, how we envision our lives. Most of us regularly consult the weather forecast as we decide what we will do or wear during the next day or even week. Imagine, for a moment, what it would mean to your logistics and psyche if you were informed that it was going to rain more or less solidly for the next five days.

fuertes barn swallow
For a Then & Now exploration of Barn Swallow arrival dates, CLICK ON THE ABOVE IMAGE.

That thought experiment might help illustrate one of the primary initial motivations behind the development of the science of meteorology in North America: agronomy. Given our current dry spell, if you’re a farmer, the thought of a good soaking rain might be a relief, and might inform whether or not you decide to plant now or wait until next week. Our modern ability to make those predictions is clearly of use to gardeners of all ilks.

However, despite the advances we have made in short-term weather forecasting, our abilities to predict weather at the larger scale remains sketchy. The National Weather Service dares to make predictions nearly a week in advance, but, in my experience, that seems to be pushing the envelope, and two or three days out seems to be the usual limit of reliability. Despite centuries of efforts, the Farmers’ Almanac year-long forecast may pique one’s curiosity but rarely alters one’s plans.

Two hundred years ago, when access to food grown elsewhere was more limited, knowledge of what the growing season would bring, even a couple of weeks ahead of time, was even more crucial. This was especially true in Spring, when an earlier planting might mean quicker crops but a greater risk of frost.

In a similar vein, while local experience can give us important insight into when to plant familiar crops, what happens when you need to know when, or even if, to plant a novel crop? Plant hardiness maps and growing-degree-day models give the modern planter some hints, but what was a St. Lawrence County farmer of 1830 to do if a cousin on Long Island sent along some new but highly recommended seeds? If that cousin were to say ‘plant these around the 25th of April’, that advice might, given the wide difference between these two NY climates, be worse than useless. If, on the other hand, the cousin were to say something like, plant these ‘when you plant your corn’, or ‘a week after your cherries bloom’, or even, ‘round about when your Martins arrive’, then the advice would be more usable.

frugs
For ‘state of the Spring’ exploration of the historical data, CLICK ON THE ABOVE IMAGE.

It was apparently this desire to facilitate the sharing of agronomic advice that prompted the New York State Regents to begin their three-decade long exploration of the State’s climates and seasons. As Simeon De Witt, the man who some 30 or more years later was to initiate the Regents’ work, put it in 1792,

as the state of vegetation is very different in different climates at the same time, without knowing what allowances are to be made on this account, the farmer, in one climate, will not be able to apply in his practice the experiments on husbandry made in another.

He continued that such work will necessitate,

besides common observations on the weather, observations on the annual commencement, progress and maturity and decay of vegetation, made in various parts, for a number of years; the averages whereof may be taken for standards by which to exhibit a comparison of climates… The remarks on the vegetation should commence with the first appearance of it in the Spring, and be made on grass [a more encompassing term historically] in general, the budding of trees, the flowering of plants, the maturity of the several kinds of winter grain and fruit, and the falling of leaves, and other symptoms of decay in the fall.

 

In the early 1800s, the New York States Regents supervised, amongst other educational institutions, some fifty or so ‘academies’. Academies were apparently public/private hybrids that were the combined high schools and prep schools of their era. They offered additional instruction beyond the traditional “3 R’s” of the basic public schools. Aside from advanced courses in reading, ‘riting, and ‘rithmitic, students were taught topics such as classical languages, rhetoric, surveying, philosophy, botany and astronomy. Graduates of academies might hope to continue to college or to enter business, the clergy or education. As market forces probably dictated, academies were scattered across the State. What better network of facilities and able minds for beginning to unravel the mystery of the State’s climatic topography?

mapleforsythia
Like yellow? For an exploration of why the yellow of Forsythia (left) was missing in our historical data and of the flowering and leafing out patterns of Maple’s (right), CLICK ON THE ABOVE IMAGE.

 

Thus on 1 March 1825, the Regents approved De Witt’s proposed meteorological project. Participating academies received a New Lebanon-made Kendall thermometer and rain gauge; however, it was a BYOWV (Bring Your Own Wind Vain) affair. They also received instructions not only on how to collect and report their measurements but also on how to make a variety of additional observations, from notes on the ‘progress of the seasons’ to descriptions of celestial events such as Aurora and distinctive clouds or solar phenomena.

The effort was maintained until the Civil War, bolstered after 1850, by a nationwide project undertaken by the Smithsonian Institute and modeled substantially on the NY enterprise. There are a wealth of data. By the time we have finished entering the phenological (i.e., the seasonal events) information, we expect to have over 12,000 individual records of when certain plants flowered, when frogs called, when birds arrived, and when farmers planted or harvested.

These data are a trip back in time, a geographically-specific glimpse of human and natural history that starts almost 190 years ago. One can find arrival times for Passenger Pigeons, flowering times for bygone hedge plants, and a diary of farm activities. However, this collection is not meant just as a portrait of the past, but also as a perspective on the present.

currants plate
We used the ‘Progress of the Seasons’ data to explore patterns mid-19th century fruit growing in NYS. If you’re curious, CLICK ON THE ABOVE IMAGE.

In these days of changing climate, the records can give us a valuable historical baseline for charting change, in much the same way as work with Thoreau’s journals has helped spur climate change understanding in Massachusetts (see link below). Furthermore, what a story and suite of activities to motivate the creation of a school-based phenology network! The fact is that finding equivalent modern information for comparison with these historical records is not so easy (although links below will lead you to some valuable modern initiatives). A multi-school program could thus not only provide useful data, but also involve students in a diverse combination of historical, biological and analytical activities.

The search for immediate weather and climate understanding has largely become the realm of complex models and highly developed measurement technologies such as weather satellites. Perhaps this has long since antiquated the application of the Regents records to the questions for which they were originally intended. And yet, in ways probably not dreamt of by those who gathered the information, these data have become even more pertinent to our understanding of climate and change, not at the scale of days, weeks or years but at the scale of decades and centuries.

Our goal with the first phase of the Progress of the Seasons Project is to try to highlight this relevance by digitizing the data and sharing it in easily accessible and stimulating forms. If this sparks interest, then we can think of developing ways of bringing the Project into classrooms in future years.

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We looked at Frog calling date as a way of predicting Apple and Cherry bloom; and also at how Frog calling and Apple flowering dates varied between two sites. To explore our conclusions, CLICK ON THE ABOVE IMAGE.

 

The work is on-going. We have been presenting weekday summaries in the form of “this date in phenological history” postings to our Progress of the Seasons blog (which has provided some of the examples included above) and have created a New York State Phenological History Browser. Want to know when those Swallows arrived in Kinderhook in 1835? Just use our browser to look it up! (And thank some forward-thinking 19th century scientists for your ability to do so.)

 

More Useful Links

Our Background Page – More information on the Regents’ project, including a map and list of participating sites

Field Guide to the Seasons – Local author Janice Goldfrank’s nifty ibook guiding you through 19 seasons in the year, from Icicle Season through Blueberry Season and on into Oak Season.

The National Phenology Network – engrossing displays and reports on data nationwide; we may submit any regional records we gather to them for inclusion in the larger data set.

The New York Phenology Project – a New York State affiliate of the national network; has some dandy resources for following the phenology of particular species.

Journey North – a live tracking of bird and butterfly migrations and various other seasonal events, great maps.

Project BudBurst – A plant phenology project with lots of materials for teachers.

The Phenology of Walden Pond – Richard Primack’s Boston University web page and blog; Dr. Primack has been comparing  Thoreau’s phenology data with those of the modern day. A great side-by-side comparison for New York.

 

 
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Posted by on May 7, 2015 in Uncategorized

 

Our Slave-making Ants

by Kyle Bradford.

 foto 1

Winter is here and ants have burrowed deep underground or have sealed themselves off in whatever medium they nest in. Some have filled themselves with glycerol (a kind of antifreeze) and fat reserves to feed on. In any case they are hibernating; giving ant collectors time to reflect on observations from the field season.

This year was a fruitful one for our ant work. We added four species to our County List. For the first time in over two field seasons, we witnessed slave raids on multiple occasions. We even had a friend in the County contact us about seeing this phenomenon. Our firsthand observations resulted in a compilation of photos and gave inspiration to dive deeper into this amazing ant behavior.

 

Some background on slave-making.

What is curious about slave-making ants is that they have evolved only in the temperate regions of the world. Only 50 ant species out of the 12,500 described are known to have this lifestyle (see reference 2). In the Field Guide to New England Ants, Aaron Ellison and colleagues include ten slave-making species, which are currently known from the region (3). The remaining 40 species occur in the rest of temperate North America, Europe and Asia. Out of the ten known from New England we have found five of these to reside in Columbia County.

 

Table 1: Slave-making species recorded for New England and Columbia County, NY.

Species Recorded in New England Recorded in Columbia County, NY?
Formica aserva Y
Formica creightoni N
Formica pergandei N
Formica rubicunda Y
Formica subintegra Y
Harpagoxenus canadensis N
Polyergus cf longicornis N
Polyergus lucidus Y
Polyergus montivagus N
Protomognathus americanus Y

Although we say “slaves,” ant slaves are not really analogous to slaves in human society. Instead ants “enslave” different species from their own. Additionally, the slaves in the ant colony are not forced to do anything novel – they just carry on the same tasks as they would have in their own colony. This is more akin to humans domesticating animals for work.

Slave-makers are considered parasites. A parasite is an organism that is dependent on a host for at least part of their life cycle. Slave-maker queens depend on a host to start a colony. In an ant colony all of the workers you see are sterile females. However, there is one queen or in some species multiple queens in the nest who are laying eggs. These eggs metamorphose from larvae to pupae and then into a sterile female, a winged queen, or a winged male. Winged queens and males are only produced for reproduction, whereas sterile females do the work around the nest. At some point in the year, often late summer, the nest will have a reproductive flight referred to as a nuptial flight. All of the winged queens and males will exit the nest to mate. The mated queens then shed their wings and attempt to find a nest site and lay their first eggs.

The difference for slave-making or parasitic species is instead of finding their own nest site they find a host species’ nest and attempt to take it over. They do this by removing or killing the host queen. The benefit of being a parasite is that the queen already has an established, successful nest to start in with plenty of workers to help raise her first young.

Generally, survival rates of newly-mated queens are extremely low. This is especially true in cold climates where harsh weather really makes survival difficult. A parasitic lifestyle may have higher survival rates. This may be part of the reason why slave-makers have evolved in cold climates and not in the tropics.

For ant parasitism to work, the parasite queen must trick the host workers into thinking she belongs in the nest. Ants distinguish their sisters from other ants by their specific pheromones. Parasitic queens have to smell like the nest. The slave-maker queen may do this in a variety of ways, including covering herself in the guts of a queen or worker she killed.

Eventually, as the new queen’s eggs hatch and older workers die, the host species workers begin to be replaced by the parasitic species. This can become a problem because many parasitic species are dependent on host workers for survival. Some more advanced slave-makers (obligate slave-makers) depend completely on their hosts for nest maintenance, foraging, and brood care (nurturing ant eggs into adult ants). When obligate slave-makers experience a shortage of host workers to do such duties around the nest, the parasite workers go on a slave raid.

Generally, raids are most likely to occur during hot, sunny summer afternoons. The process begins when workers are cued that there’s a need for more slave labor. Slave-maker “scouts” exit the nest and begin their search for a host nest. When a nest is found, scent trails are laid back to the home nest. Slave-raiders are recruited, and the stealing of ant larvae and pupae begins. For most slave-making species, the already-enslaved host never participates in slave raiding. However, host species of the western US slave-maker Formica wheeleri have been known to join in on raids (5).

Slave-makers can travel great distances (by ant standards) for their kidnapping activities and are skilled at finding nests. In one raid we witnessed, they traveled nearly 90 feet to the host nest. The host nest was inconspicuous, being hidden under leaf litter. If I hadn’t followed the raiding party I wouldn’t have known a nest was there.

 

Some details on the lives of two of our most conspicuous slave-making species

 Polyergus lucidus, the Amazon Ant.

This is our most fascinating slave-maker. Commonly known as Amazon Ants, Polyergus lucidus is a magnificent shiny, ruby red and has unique mandibles that resemble the curved blades of sickles. These mandibles are specialized for combat but are impractical for chores around the nest.

 foto2 The Amazon’s piercing mandibles

This species does not live in the Amazon or any other tropical region. Instead they are endemic to northern North America. Their distribution is from Southern New England west to Wisconsin and south to high elevation meadows in the Carolinas (9). The common name refers to the Amazon warrior women in Greek mythology, this is fitting because all worker ants are females. These ants like to fight and pillage, but otherwise live quite a royal lifestyle. They are incapable of feeding themselves or rearing their young, instead depending on slaves for these tasks.

foto 3

The above photo shows a winged Amazon queen on the left and the slave species Formica incerta on the right. In any ant colony, the queens are crucial to the success of a species. So when there are winged virgin queens in the nest, workers are likely to protect them. In the photo the slave species is escorting the Amazon queen back to safety after being disturbed. This task wouldn’t be done by an Amazon worker. In fact, when an Amazon nest is disturbed the Amazon workers run around erratically trying to sink their teeth into the intruder. If they can’t find the intruder, they quickly go back underground leaving the slaves to fix the damage.

foto 4 An Amazon worker on the attack.

The Amazons seem rare in Columbia County, and are listed by the IUCN as “vulnerable to endangerment.” We have only seen them in two locations: in a Philmont cemetery and a pasture at Hawthorne Valley. The Philmont cemetery colony was found in 2013. When I revisited it in 2014 it was no longer active. Amazons may have relocated their nest. Nest relocations can be quite common for some ant species. However, one distinctive reason among slave-makers is to relocate to gain access to more host colonies after local exploitation (1). In 1910 Wheeler suggested this for Amazons, although some have speculated that there are other reasons for Amazon nest relocation (6, 7).

It is also noted that Amazons are susceptible to local extinction, because they are dependent on large stable populations of host species. If abundant host populations are not stable, because of disturbance, Amazons are not likely to survive in that location (4).

foto 5

foto 6   The two sites where we have found Amazons. They tend to like dry open habitats where there is an abundance of their host species Formica incerta.

Grace Barber, a graduate student at UMass Amherst, has been working on ants in the Albany Pine Bush. She has found Amazons there and has posted a fantastic video of their slave raid!

 

Formica subintegra

Two of the slave raids we witnessed this year were from the species Formica subintegra. We have found these ants in open forest and meadow habitats.

map 7subintegra is widespread in the County.

One raid happened on the sun exposed ledges around No Bottom Pond in Austerlitz during an August afternoon. The following photographs are from that raid.

 

foto 7Part of the subintegra raiding party.

 

 foto 8An unlucky host species becomes defenseless as masses of raiders enter the nest.

Formica subintegra have special enlarged glands that secrete what EO Wilson has termed “propaganda substances” (8). These chemicals are effective in alarming the host colony. Instead of fending off the raiders they are put into a frightened frenzy out of the nest. This makes it much easier for the slave-makers to enter the nest and take brood. Any resisting hosts that haven’t fled are out-numbered and easily defeated.

Generally, raided host nests by subintegra are not destroyed. I have not seen any description of subintegra killing a queen during a raid, and presumably a raided nest can recover.

 

foto 9A subintegra looks on as two of her sisters drag out a decapitated host as they start raiding the nest.

foto 10subintegra carrying a stolen pupa back to her home nest.

 

It was a pleasure observing these slave raids in the field. These animals that share our landscape are truly unique and fascinating. If you are out on a hot summer day in a dry oak forest or an old field keep an eye on the ground. You might be lucky enough to see a march of Amazons or a raid in the leaf litter.

 

 

For Further Reading

 A Field Guide to New England Ants – Aaron Ellison – This is what we use for species level identification. It has ecological information for each species and is geared toward the layperson. It does have an overview of basic ant ecology.

Journey to the Ants – Bert Holldobler and EO Wilson – A condensed, non-technical overview of interesting myrmecology (ant studies) especially that of Holldobler and Wilson’s. It is combined with photographs and neat illustrations. Has a chapter on social parasites which includes slave ants.

Adventures among Ants – Mark Moffett – A taste of ant ecology from around the world with spectacular photographs. Also has a chapter on slave-makers with information pertaining to species we have.

 

 Full Works Cited

  1. Apple, J., Lewandowski, S., & Levine, J. (2014). Nest relocation in the slavemaking ants Formica subintegra and Formica pergandei: A response to host nest availability that increases raiding success. Soc.
  2. D’Ettorre, P., & Heinze, J. (2001). Sociobiology of slave-making ants. Acta Ethol, (3), 67-82.
  3. Ellison, A., Gotelli, N., Farnsworth, E., & Alpert, G. (2012). A Field Guide to the Ants of New England. New Haven: Yale University Press.
  4. Fisher, B., & Cover, S. (2007). Ants of North America: A Guide to the Genera. Berkeley: University of California Press.
  5. Holldobler, B., & Wilson, E. (1994). Journey to the Ants: A Story of Scientific Exploration. Cambridge: Harvard University Press.
  6. Kwait E.C. and Topoff H. (1983). Emigration raids by slave-making ants: a rapid-transit system for colony relocation (Hymenoptera: Formicidae). Psyche (90), 307–312.
  7. Marlin A.J.C. (1971). The mating, nesting and ant enemies of Polyergus lucidus Mayr (Hymenoptera: Formicidae). Am. Midl. Nat. (86), 181–189.
  8. Regnier, F., & Wilson, E. (1971). Chemical Communication and “Propaganda” in Slave-Maker Ants. Science, 172(3980), 267-269.
  9. Trager, J. (2013). Global revision of the dulotic ant genus Polyergus (Hymenoptera: Formicidae, Formicinae, Formicini). Zootaxa, (4), 548-548.
 
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Posted by on January 8, 2015 in Uncategorized

 

Nature Exploration at the Lewis A. Swyer Preserve in Stuyvesant, NY

The freshwater tidal swamp of the Lewis A. Swyer Preserve in Stuyvesant was the destination of our Natural History Outing on July 6th. The Hawthorne Valley Farmscape Ecology Program facilitates these Natural History Outings as a way to invite anybody to participate in the joy of discovering and documenting the plants and animals of different areas in Columbia County. These outings are not guided nature walks, but impromptu explorations, often at locations we have never (or at least not in a long time) visited ourselves. Please check our calendar if you are interested in participating in future outings.

The Lewis A. Swyer Preserve, which is owned and managed by The Nature Conservancy, was established to protect one of the five largest areas of freshwater tidal swamp in New York. It surrounds the mouth of Mill Creek and is influenced by the twice daily tidal change in water level of the Hudson River (~ 4 feet!) and Mill Creek. To learn more about the regional significance of this type of habitat, please read here.

This posting illustrates some of the plants, plant communities, and animals we found on July 6th, while walking on the 1/2 mile boardwalk that connects the trailhead on Route 9J (2 miles north of Stuyvesant Landing) to a little observation tower next to the railroad tracks at the mouth of Mill Creek.

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The trees of the freshwater tidal swamp forest along the boardwalk are mostly Swamp White Oak, Red Maple, and three species of ash (White, Green, and Black Ash).

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The most prominent plants on the ground under the trees are Hog Peanut, Skunk Cabbage, and Sensitive Fern.

3 Lily

Canada Lily was a notable presence during our visit.

3a Lily 1

Some where browsed by deer, who seem to enjoy eating the flower buds, but many were in full bloom.

4 Lily 3

Canada Lily blossom with its companion plants, Sensitive Fern and Hog Peanut.

6 IMG_0034

Poison Ivy is a constant presence along the sides of the boardwalk with enormous vines climbing many of the trees and forming canopies of their own below and intermingled with the trees canopies. The leaves surrounding the largest bole in this images, as well as the leaves entering the image from the right, are all Poison Ivy. Needless to say, we were very thankful for the boardwalk which kept us at a safe distance from most of it.

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Part of our group trying to catch a glimpse of an elusive bird high up in a tree. Otter (in red T-shirt) is trying out his new camera to see if he can get a shot…

8 Great Crested Flycatcher

… and succeeded in documenting this Great Crested Flycatcher.

The most common shrub along the boardwalk is Spicebush, which was so common that we forgot to take a picture.

However, there were some other interesting plants along the way:

9 American Hazel

American Hazelnut, which we rarely see with beautiful fruits. And fruits they had…

10 American Hazel 2

When in fruit, our two native Hazelnuts are easily distinguished. The fruits of American Hazelnut are surrounded by “fringed” (botanists speak of “laciniate”) bracts (leaf-like structures), while the fruits of Beaked Hazelnut are covered by bracts which are prolonged beyond the nut into a long, slender beak. In Columbia County, American Hazelnut is usually found in the western part, near the Hudson River, while Beaked Hazelnut is the common species found in the Taconics and the hills in the eastern part of the County.

12 Ninebark

Ninebark is another shrub which is found in our County exclusively along the Hudson River. It is a member of the Rose family, with leaves reminiscent of Hawthorn, but its fruits are dry, four-parted capsules (a bit like the core of an apple without the apple around it).

12a IMG_0013

Carrion Flower (so named because of the somewhat rotten smell of its flowers) is a non-woody vine related to Greenbriar. Its leaves have a characteristic venation with several parallel veins and only very faint cross-veins. The fruits ripen to a very dark blue color.

13 spider

A Fishing Spider of the family Pisauridae was guarding its nursery web (bottom left), filled with tiny spiderlets. The body of the mother spider was about an inch long.

15 IMG_0231

A Daddy Long-legs or Harvestman, a relative of spiders in the order Opiliones. Daddy Long-legs differ from true spiders in the way they eat: Spiders can only suck liquid food, while Daddy Long-legs can eat small particles of insects, plants, fungi, or dead matter.

16 IMG_0204

This and the following image show two different species of Robberfly or Assassin Fly. This group of insects are powerful predators on other insects. They usually catch their prey in flight and then insert their mouthparts to suck out the juices.

17 IMG_0212

 

18 IMG_0017

One of the small tributaries draining from the freshwater tidal swamp into Mill Creek at receding tide.

19 Pickerelweed

Pickerelweed is emerging at the shore of the creek at low tide. During high tide, most of the stalks are submersed and only the leaves and blue flowers stick out of the water.

20 IMG_0024

A section of the boardwalk near the observation tower. The tree cover is sparser here and allows a dense stand of sedges (Carex trichocarpa) to dominate the vegetation on the ground.

21 IMG_0019

Water Hemlock (Cicuta maculata), one of our most poisonous plants in the County (and totally unrelated to our Hemlock trees, but a close relative of the Hemlock that Socrates took to end his life), stands tall next to the boardwalk, surrounded by the broad arrow-shaped leaves of Arrow Arum.

22 IMG_0018

Another view from the boardwalk into more open vegetation along Mill Creek.

23 silver-spotted skippers

Two Silver-spotted Skippers frolicking around the flowers of Tall Meadow-rue.

25 IMG_0246

This somewhat blurry image was taken at a long distance because we were both curious about the butterfly and the plant, but could identify neither from where we stood. The flower shape fits with Stachys sp., and the plant is most likely Smooth hedge-nettle (Stachys tenuifolia), not American Germander, as we had guessed in the field. The butterfly is one of the Skipper species, most likely Broadwing or Dion Skipper.

29 buttonbush w least skipper

This spherical inflorescence belongs to Buttonbush, which was in full bloom and attracted a variety of butterflies and other insects. Here pictured is the Least Skipper. We also saw an Azure and a Little Wood Satyr feeding on Buttonbush flowers.

According to Kathy Schmidt, a local snail expert, who is also known as the talented nature illustrator whose beautiful drawings adorn most outreach materials produced by our colleagues from Hudsonia Ltd., the following (and last) image is of an Ovate Ambersnail (Novisuccinea ovalis), a native air-breathing land snail which loves humid microclimates.

30 snail

 

 
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Posted by on July 22, 2014 in Uncategorized