The sun sets the Vermont forest ablaze with color
© Kent McFarland
The month of October reminds us of the cyclical nature of life. Like spring, autumn is a season of change. The forested hills fade from summer emerald to a watercolor painting of red and gold and brown. Here’s your field guide to some moments that you might not otherwise notice during these few precious weeks that feature colored hills beneath a deep blue sky.
By Spencer Hardy
On a warm, sunny day in October, any large clump of asters is likely to be buzzing with life. But unlike earlier in the fall, the cast of characters is often pretty limited, being dominated by European Honey Bees (Apis mellifera), Common Eastern Bumble Bees (Bombus impatiens), and drone flies (genus Eristalis). And yet October still has its fair share of surprises (and great low-angle light for photography!).
With many formal research projects done for the season and the windows of warm weather shrinking, the Vermont Wild Bee Survey has relied heavily on community scientists–principally through iNaturalist–to document the bee fauna at the tail end of summer. With over 2,400 observations of 46 species, we have not been disappointed. Some incredible bee records have been shared this month, including nesting Golden-tailed Leafcutters (Megachile relativa) and a male of the summer active Broad-handed Leafcutter (Megachile latimanus). Undoubtedly though, the most fascinating October observations have been of the S1 Ground Cherry Sweat Bee (Lasioglossum pectinatum). This is a globally rare bee that only collects pollen from ground cherries and tomatillos (genus Physalis) and was first discovered in Vermont in 2020. Over the past 3 years, observations from two iNat super users on opposite sides of the state have demonstrated that this rare species often flies into mid-October in association with cultivated tomatillos, and that it also visits various Asteraceae at the end of the season, presumably for nectar.
All this goes to show, don’t hang up the net and camera quite yet–you never know what surprises are still awaiting discovery, even in your own yard!
By Allie Radin
As fall comes to the Upper Valley, pumpkins appear on farm stands and nature starts to wind down for winter. One insect found in Vermont stays ready for fall all year round: the Halloween Pennant dragonfly (Celithemis eponina). Named for its distinctive wing coloration, the adults of this species sport orange to yellow wings with dark-brown bands reminiscent of Halloween color schemes.
With a range encompassing the eastern United States, this dragonfly can be found from Texas to Maine. The Halloween Pennant is often found near water, sitting on the tops of vegetation and waving in the breeze like a, well, pennant. Halloween Pennants, like other dragonflies, are proficient aerial predators that hunt insects. Unlike some other dragonfly species, the Halloween Pennant will still be active in wind and rain.
While this species is named for fall festivities, the Halloween Pennant is most readily found in Vermont during the summer months. You can record your own sightings of the Halloween Pennant in the Vermont Atlas of Life on iNaturalist or Odonata Central. The easiest identifying features are its wings, which have a distinctive striping pattern. The Halloween Pennant lookalike species, the Calico Pennant (Celithemis elisa), has clear wings with smaller brown spots that only touch one side of the wing. Halloween Pennants, on the other hand, have brown bands that stretch from top to bottom of the wing. Perhaps you can be an uncommon Halloween Pennant sighting this fall–there’s still time to make a Halloween costume!
By Dana Williams
As the weather cools and walking under oak trees becomes a perilous activity due to falling acorns, many animals are thinking of the long cold winter ahead–specifically how they plan to survive it. Migration may be at the forefront of birders’ minds this time of year, but our year-round residents have plenty of strategies too. Caching, or stockpiling food, is one such strategy that is a common behavior to see in the fall, including from some of the non-migrating members of the Mountain Birdwatch focal species list.
As you’re walking in an evergreen forest, look at the base of the trees and see if you can spot a large mound of pine scales and cores. This is a midden, and the scolding you receive is likely a Red Squirrel (Tamiasciurus hudsonicus) warning you away from pilfering their larder hoard of green conifer cones. Larder hoarding is a method of storing food in a central, defensible location. Admittedly, middens are hard to miss when a single one can hold the remnants of over 6,000 cones and be up to 30 feet across. These middens are built up across several years (and several squirrels) with layers of cone castoffs becoming an insulating layer that keeps newly stored cones moist, cool and closed to protect the nutrient-rich seeds inside. Midden piles are a squirrel’s key to winter survival, and sometimes mother squirrels—especially those with late litters—will carve out parts of their territory to pass on to their offspring in order to improve their chances of survival.
Black-capped Chickadees (Poecile atricapillus), on the other hand, are scatter hoarders that spread small stockpiles of food across a landscape. This prevents them from having all their eggs in one basket, so to speak. Even if one food source fails, they have others to fall back on. A single cache can fail for any number of reasons, including the food going bad, the location being forgotten, or cached items being raided by friends and foes alike. In fact, flockmates watch when and where individuals make caches and up to 5% of caches may be immediately stolen. When chickadees are visiting your bird feeders this winter, keep an eye out for individuals who grab a seed and fly away from their flock–they’re likely going to cache it for later.
As the weather gets colder and caching behavior increases, be on the lookout for stashes of seeds, plants, insects, spiders and more in the hollow stems of plants, under tree bark, inside curled dry leaves, in the corner of a shelf in your barn, stuffed into the nooks and crannies of moss or buds, or even piled into an old bird nest. You can share your animal sign observations to iNaturalist, or you can learn to recognize some of them and help identify the observations of others! (https://www.inaturalist.org/observations/identify).
By Eric Hanson
Those lucky enough to still be spending time on their favorite Vermont lakes may have noticed the disappearance of their resident adult loons, even with chicks still around. Carol Brooke-deBock has been following the two chicks on South Pond in Marlboro but has seen only a single adult since late August. She actually observed one chick take a short flight, preparing for migration, on September 10. Other people have observed congregations of 4–18 visiting loons (usually on larger lakes). Denis LaPointe reported a consistent group of eight to nine adults on Norton Pond, and Nina Sharp has been sharing Caspian Lake with a group of 10 plus loons during her daily rows.
So, when do loons take to the skies? To help answer that question, I’ll refer to a study on 32 loon pairs in Maine and New Hampshire by Lee Attix, who worked for Biodiversity Research Institute at the time. Starting in September, Lee followed loon pairs twice a week until late November (most of the males and females were banded and thus could be identified). He found a lot of variability in the timing of loon departures but also some general trends. As noted above, some adults start to move or even leave in September, while others stick around until late November. Chicks tend to depart in late October and November, but like the adults, some will leave in late September. Others never seem to get that migration restlessness (referred to as “zugunruhe” in textbooks) and are still on the water when ice starts to form. Some of the study’s major findings include:
Most New England loons spend the winter off the Northeast coast, with a short migration period of only one to two days. Juveniles figure out how to reach the ocean on their own and likely take a much longer time getting there. Based on a sample size of one in a satellite telemetry study (Kenow et al., 2009), a lone Adirondack (NY) juvenile left in late November and took 56 days to puddle jump from lake to lake, eventually reaching Long Island Sound in January.
Juveniles that reach their second year are considered immature birds, and they usually spend several years on the ocean before returning to their natal lake region as sexually mature individuals. Loons from the central part of North America will overwinter along mid-Atlantic and southeastern coasts and the Gulf of Mexico—they have a lot further to fly than New England’s loons!
One study that followed two loons from Saskatchewan revealed that one individual migrated to Lake Michigan and straight down to the Gulf of Mexico, while the other loon flew to the same location in the Gulf via Lake Erie, the Chesapeake, and across the Florida Panhandle (Paruk et al., 2014). How did they choose which route to take? We don’t really know, but once a loon learns a route, they stick with it for years to come.
After spending the winter eating seafood on the ocean, loons will return to northern, forested, freshwater lakes and ponds in the spring, usually in April or early May. The magic of migration in all animals is fascinating; what initiates it, and how do species find their way back in spring to the same lake or forest stand? The sun, stars, Earth’s magnetic field, learned behavior, and genetics are several of the myriad factors that influence these amazing journeys.
The yellow streaming blooms of American Witch-hazel (Hamamelis virginiana) can be found in the understory in October when most leaves have fallen to the ground. The long, bright-yellow petals, sweet smell of nectar, and pollen-loaded stamens suggest insects as the primary mode of pollination; but with the cool temperatures, most insects are finished for the season. Who visits this late bloom?
The entomologist Sigmund Graenicher, working in Wisconsin near the turn of the 20th century, observed insect visitors from 44 genera, including bees, wasps, flies, and moths. Decades later, University of Vermont biologist and naturalist Bernd Heinrich discovered that a group of owlet moths feed at the flowers on cool evenings in October, when they need sugars to fuel the high body temperatures (~86° F) necessary for flight.
When the moths are at rest, their body temperature falls to the air temperature around them and they enter a state of torpor. During daytime when temperatures fall below freezing, they hide under insulating leaves on the forest floor. But when night falls, they have to fly to find food and mates, which requires raising their body temperature—maybe by as much as 50° F—to activate their flight muscles. To do this, they shiver. On long flights they will sometimes repeatedly stop and shiver to warm up again. All of this is powered by the sugars they consume.
In a 1987 Scientific American article Heinrich wrote, “Adult winter moths generally feed on the sap of injured trees, although on late-fall nights a few years ago I saw many of them feast on the blossoms of witch hazel, Vermont’s latest-blooming plant.”
The owlet moths that pollinate American Witch-hazel are in the family Noctuidae, and they include: Grote’s Pinion Moth, (Lithophane grotei), Morrison’s Sallow (Eupsilia morrisoni), and the Three-spotted Sallow (Eupsilia tristigmata).
Add your observations to the Vermont Atlas of Life on iNaturalist and help us track witch-hazel flower phenology and some of the insects you might find visiting the flowers.
