Snapping Turtle Nests Raided
Female Snapping Turtles spend a lot of time and effort finding suitable sandy soil in which to dig their nest and lay their eggs. Some turtles have been found laying their eggs as far as a mile from the nearest water source. Once she has laid her eggs and covered them with soil, the female snapper returns to her pond, leaving her eggs to hatch on their own, and the hatchlings to fend for themselves.
It is estimated that as many as 80 to 90 percent of all turtle nests are destroyed by predators, weather conditions and accidental disturbances. Most of the damage is done by predators – skunks, raccoons, foxes, crows, among others. Most nests are discovered by smell, and most are raided at night. The fluid that coats the eggs, that is lost by the mother during egg laying or is lost through breaks in the eggs, produces a smell that is easily detected by predators. While a majority of nest raids happen within the first 48 hours of the eggs being laid, studies have shown that predation occurs over the entire incubation period (June – September). The pictured Snapping Turtle nest was dug up and the eggs consumed 10 days after they were laid.
If you are aware of a spot where a turtle dug a nest and laid eggs, you can try to protect the nest from predators by placing either a bottomless wire cage or an oven rack over the nest site, and putting a heavy rock on top. The tiny hatchlings will be able to escape through the openings but hopefully, if the rock is heavy enough, raccoons and skunks will become discouraged and give up trying to reach the nest.
The next Naturally Curious post will be on 7/5/17.
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Saving Grassland Birds
Grassland birds are disappearing in the Northeast. Among the species affected are Bobolinks, whose numbers have been declining since the 1900’s. One of the primary reasons for this decline is the mowing practices of farmers. Boblinks nest on the ground, in fields. Farmers’ now mow earlier and more frequently than in the past. Their first mowing (which has the highest protein content and the greatest yield) coincides with Bobolinks’ peak nesting time. These birds migrate 6,000 miles from their wintering grounds in South America and arrive in New England to breed in mid-late May, with young hatching in mid-June. Needless to say, many of their nests fail to produce young given the current mowing schedule of many farmers.
An organization called The Bobolink Project was formed to help farmers protect grassland birds. They accept donations which they use to reimburse farmers who sign up to delay their first cut of hay. This allows nesting grassland birds such as Bobolinks, Eastern Meadowlarks, Savannah Sparrows, Upland Sandpipers, and Grasshopper Sparrows to hopefully remain undisturbed until the successful fledging of their young. To learn more about adjusting mowing schedules to outside the peak breeding season of grassland birds (May 15 – August 15) and The Boblink Project, go to www.bobolinkproject.com .
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Wolf Spiders: Maternal Duties Coming To An End
Just a few days ago, this adult female wolf spider’s abdomen was covered three-spiders-deep with newborn wolf spiderlings. Wolf spiders, unlike most spiders, do not abandon their eggs. They carry their egg sac around with them until the eggs hatch, grasping it with spinnerets located at the tip of their abdomen. Not only does the female not desert her eggs, but she also provides protection for her newborn spiders. After hatching, the several dozen or more young crawl up onto her abdomen, where they ride around for several days. Eventually they drop off and begin a life of their own. In this photo, only three spiderlings remain (look closely) and they abandoned ship within the hour.
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Cooperative Warbling Vireo Nestlings
Shortly after being fed, most songbird nestlings produce what is called a fecal sac – a mucous membrane (usually white with a dark end) that contains their excrement. This sac enables easy removal of the chicks’ waste by the parents. In an effort to keep its young healthy and to reduce the chances of predators finding the nest, the parent takes the fecal sac in its beak, flies away and discards it some distance from the nest.
Some nestlings, including those of Warbling Vireos, are extremely cooperative when it comes to assisting their parents in keeping the nest clean. Just prior to producing a fecal sac they position themselves with their rear ends up in the air (see photo), where their parents can easily procure the fecal sacs when they appear.
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Luna Moths’ Sonar Scramblers
Luna Moths, Actias luna, are known for their hindwings’ beautiful, long, green tails. These tails are not simply decorative, nor is their primary function to attract a mate (pheromones do that). A recent study found that Big Brown Bats have an easier time catching Luna Moths that have lost their tails. Further research revealed that Luna Moths defend themselves from voracious bats patrolling the night air by spinning the tips of their two wing tails in circles. The twisting tails of the moth act like a sonar shield, interfering with the bat’s means of locating them – echolocation. In contrast with the stronger, ever-changing echoes coming off of the moths’ large flapping wings, the twisted shape of the tails create a persistent weak echo signal. According to researchers, this could make the insects trickier to catch, and harder to track as they fly.
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Cedar-apple Rust Galls Maturing
If you have both Eastern Red Cedars (Juniperus virginiana) and apple (Malus spp.) trees, you may be privy to the show of a lifetime on your cedar tree one of these days. There is a fungus, specifically a rust fungus, that needs two hosts, Eastern Red Cedar and apple trees, to complete its life cycle. In order to survive, the fungus must “move” from one host species to another.
If contaminated by the cedar-apple rust, an Eastern Red Cedar tree will have small, woody brown galls on its twigs for the better part of a year. Following a warm spring/early summer rain, these brown galls transform into orange, gelatinous growths the size of a golf ball, adorned with “telial horns” that point in all directions. The function of these horns is to disperse spores. If the spores happen to land on the leaf of an apple or crabapple tree, and conditions are just right, galls will result. These galls look very different from the cedar’s galls. Small, yellow spots on the upper surface of the leaves appear after affected apple trees bloom. The spots gradually enlarge and become yellow-orange-red. Small, raised, black dots form in the center of the leaf spots on the upper surface of the leaves as the leaf spots mature. (Apple trees may defoliate early or spots may develop on the surface of the apple as a result of this rust.) Very short, finger-like, fungal tubes protrude from the lower surface of the leaf directly below the spot which release yellow to orange powdery spores. If the wind carries them to an Eastern Red Cedar, the cycle continues. The complete cycle of cedar-apple rust takes 24 months to complete and requires infection of two different hosts.
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Black Bears Communicating
Black Bear males are not shy about making their availability and intentions known to the opposite sex. Their most prevalent means of communicating this information is to leave their scent on trees (as well as other structures, such as telephone poles– see photo) by scratching them with their claws, biting them and rubbing on them with their shoulders, back and neck. Often they will use the same marking tree year after year, with signs accumulating on the tree.
Both males and females mark trees year-round, but at this time of year, at the peak of their mating season, males are especially active markers, in order to convey their social identity, reproductive status and location to female passersby. One might consider such marking trees as ancient “scratch.com” mating sites. If you find one, be sure to look for stray hairs that have been inadvertently left behind. (photo by Alfred Balch)
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Common Green Darners Appearing
The Common Green Darner (Anax junius) is one of our most common dragonflies. often seen near ponds. The family of dragonflies known as “darners” consists of species with large eyes and long abdomens that tend to rest infrequently and when they do rest, usually hang vertically. The Common Green Darner is the only North American darner in which the male and female usually fly in tandem when the female is laying her eggs on emergent vegetation.
Up to 50 of the world’s 5,200 dragonfly species migrate and the Common Green Darner is one of them. In the fall most (but not all) adult Common Green Darners migrate south to Florida, eastern Mexico and the West Indies. Huge clouds of migrating dragonflies have been seen along the East Coast, Gulf Coast and the Great lakes in autumn. Transmitters weighing 1/100th of an ounce that have been attached to migrating dragonflies confirm that they migrate much like birds. Just like avian migrators, they build up their fat reserves prior to migrating; they follow the same flyway as birds, along the Atlantic Coast; and like birds, dragonflies don’t fly every day but stop and rest every three days or so.
Some dragonflies mate and lay eggs along the way, while others do so when they reach their destination. The eggs hatch, larvae develop and the adults head north in the spring. Unlike birds, migration is only one-way for dragonflies. It is the offspring of the fall migrating generation that migrate north in the spring. Here in the Northeast, most arrive before any resident Common Green Darners have emerged. (photo: female Common Green Darner)
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One-flowered Cancer-root Flowering
One-flowered Cancer-root (Orobanche uniflora), also known as One-flowered Broomrape, is now flowering in fens — wetlands similar to bogs, but less acidic and more mineral-rich. Covered with glandular hairs, its flower looks like it’s made of crystallized sugar. One plant produces up to five flowering stalks, each of which bears a single, fragrant, white-to-lavender flower.
One-flowered Cancer-root has no chlorophyll in the scale-like leaves that grow on its underground stem, and thus is incapable of making its own food. This parasitic plant is classified as a holoparasite – entirely dependent upon other host plants for its nutritional needs. A One-flowered Cancer-root seedling must find a suitable host plant (often sedums, saxifrages and asters) within a few days of germinating or die. The search for a host by One-flowered Cancer-root is guided by chemicals released by the growing roots of the host species. Once a host plant is located, the One-flowered Cancer-root’s root hairs exude an adhesive substance that attaches its roots to those of the host plant. Enzymes break down the cell walls of the host, and a tuber-like connection (haustorium) forms between the vascular tissue of the two plants, allowing the movement of water, minerals and carbohydrates to flow in one direction, from host to parasite. (Thanks to Shiela and Steve Swett for photo op.)
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Snapping Turtles Laying Eggs
In June, mature female Snapping Turtles leave their ponds in search of a sandy spot in which to lay their eggs. (Capable of storing viable sperm for up to three years, female snappers do not necessarily mate every year prior to laying eggs.) Once this prehistoric-looking reptile locates a suitable location she slowly scoops one footful of earth at a time up and to the rear of her, alternating her left and right hind feet. If the soil is dry and tightly packed, she will urinate on it in order to facilitate digging.
Hole made, she proceeds to slowly lift her body and release ping pong ball-sized, -colored and -shaped eggs, usually one at a time, but occasionally two, into the hole beneath her. Down she comes for a minute or two of rest, and then up she rises again to release another egg. She does this anywhere from 20 to 40 times, a process that can take up to several hours, depending on the number of eggs she lays. Then her large, clawed hind feet slowly begin to scrape the two piles of soil she removed back into the hole, one foot at a time, until the eggs are covered, at which point she tamps the soil down with her plastron, or bottom shell. She then returns to the water, leaving the eggs and hatchlings to fend for themselves.
It is hard to accept that after all the effort that has been put into this act, studies have shown that 90 percent or more of turtle nests are raided by the likes of raccoons, skunks and crows. For those nests that are not discovered by predators, the sex of the turtle that emerges from each egg is determined by the temperature it attained during a specific part of its development. Eggs maintained during this period at 68°F produce only females; eggs maintained at 70-72°F produce both male and female turtles, and those incubated at 73-75°F produce only males. The eggs hatch in September, with many of the Snapping Turtles emerging then, but in the northern part of their range, young Snapping Turtles sometimes overwinter in their nest and emerge in the spring. (Thanks to Chiho Kaneko and Jeffrey Hamelman for photo op.)
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Modest Sphinx Common & Scientific Name Correction
Poplar Hawk-moth and Big Poplar Sphinx are both common names used for more than one species of moth. Normally, the scientific name would clarify the identity of a species, but in yesterday’s post, the scientific name given was that of another moth with the same common name.
The confusion over the use of the same common names for different species of moths has led to the current use of the name Modest Sphinx for the moth depicted in yesterday’s post, with a scientific name of Pachysphinx modesta. It derived both common and scientific names from the fact that when it is seen up against a tree or other substrate with its forewings not fully extended, the bottom half of the moth is dark, as though “modestly covered” by a cloak or shawl. Thank you, Andree Sanborn, for your sharp eyes!
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Millipedes Meandering
How do you distinguish a millipede from a centipede – both multi-segmented arthropods that have a lot of legs? Although there are many less obvious differences, centipede bodies are relatively flexible and they have one pair of legs per body segment. Most of a millipede’s segments have two legs, and their tubular body is quite rigid.
Depending on the species, millipedes have between 80 and 750 legs, with most having fewer than 100, but they didn’t start out their lives with this way. When they hatch, millipedes only have three pairs of legs; every time they molt, they add more body segments and legs. When threatened, millipedes quickly coil their body into a spiral, protecting their legs and fragile underbody with their armor-like body plates (tergites).
If you come across a millipede, know that you’re looking at one of the earliest animals to breathe air and make the move from water to land. Pneumodesmus newmani, a fossil found in Scotland, dates back 428 million years and is the oldest fossil specimen with spiracles for breathing air.
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Poplar Hawk-moths Emerging, Mating & Laying Eggs
June is well-known for the giant silk moths that emerge this month, but there are other large moths that are encountered as well, one of which is the Poplar Hawk-moth (Laothoe populi). Hawk-moths, also known as Hornworms (their larvae, which feed mainly on species of poplar, usually have a horn), are a type of Sphinx moth, which are known for their fast, enduring flight. One of the more familiar species of this family is the day-flying Hummingbird Hawk-moth, which can be seen hovering at flowers while sipping nectar with its proboscis.
Adult Poplar Hawk-moths, with wingspans as large as four inches, emerge in early summer. Their life is so short that they do not have a functional proboscis and do not eat, but concentrate on mating. Females extend a scent gland from the end of their abdomen to lure in the night flying males whose large claspers are frequently wide open as they fly in to lights around midnight. The moths mate and the females lay their pale green eggs on the leaves of poplars and willows, which the larvae eat once they hatch. Fully-grown caterpillars pupate and overwinter in shallow burrows in the ground.
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Gray Treefrogs Well Camouflaged
If there is an amphibian that is a master of disguise, it has to be the Gray Treefrog (Hyla versicolor). This remarkable frog is capable of changing its color (gray, green or brown) to match its environment within half an hour, a process called metachrosis. Shades of gray are most common with black blotches on the back while green colors are more prominent during the breeding season and in yearling frogs.
Being a treefrog, it has large, round, sticky toe pads that help it cling to trees and shrubs, where it spends most of its time. Survival is more likely if predators don’t detect you, so Gray Treefrogs have evolved to look a lot like bark.
When the temperature reaches 59° F. the males’ bird-like trilling can be heard coming from foliage next to and hanging over their shallow breeding pools. If you wish to set eyes on a Gray Treefrog, now is the time, as they are calling and a silent Gray Treefrog can be extremely difficult to find!
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Clintonia Flowering
A shade-loving member of the Lily family, Clintonia (Clintonia borealis) forms colonies throughout moist woods of the Northeast. It reproduces via rhizomes as well as seeds, which accounts for its colonial habit. This wildflower has many common names, among them Bluebead, which reflects the brilliant blue color of its summer berries.
Native Americans used Clintonia as an eye and heart medicine, as well as a dermatological and gynecological aid. Of particular note are its thick, fleshy leaves, which made perfect palettes for Chippewa children who are said to have delighted in making designs in the leaves with their teeth. It’s likely they did this with young leaves, which taste something like cucumbers, as opposed to older leaves, which are tough and bitter.
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Hen Turkeys Protecting Poults
Wild Turkey chicks, or poults, can be seen these days scurrying at their mother’s feet, trying to keep up with her as they forage in fields for grasshoppers and other insects. How the hen turkey reacts to a human (or other) threat depends on the age of her poults. If they are very young (under a week old), she huddles stock still with her brood in a frozen position. With wings and tail spread, she provides them with shelter. If they are detected, she gives a vocal command to her young to remain “frozen,” and feigns an attack on the intruder, simultaneously making a “putting” sound to quiet her chicks. By the time they are a week old, poults tend to evade possible predators by running away. At nine days old and later, most poults fly into low vegetation when threatened. By the time her brood is three weeks old, the hen commands them to fly into trees at the sign of danger.
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Tamarack Seed Cones Are Upright!
Tamarack Cones Maturing
Tamarack (Larix laricina), also commonly called Eastern or American Larch, grows and drops a new set of leaves every year, just like maples, birches, or other deciduous trees. Found in many bogs, it is the only native deciduous conifer in the Northeast and is known for its green needles which turn a showy yellow in the fall before falling to the ground as winter approaches. Equally dramatic, however, are its seed cones. They are the smallest of any larch (1/2” to 1” long) and have only 12 to 25 scales. At a certain point (right now) in their spring growth they are bright maroon and resemble tiny roses. They eventually turn brown and open to release the seeds, four to six months after pollination.
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Turkey Vultures Preening
Turkey Vultures spend much of their day gliding and soaring with their wings out in a dihedral position, scavenging for carrion. This requires each of their wing feathers to be aligned in the most optimum position relative to its adjacent feathers and the bird’s body shape. In order to achieve this alignment (as well as dust, dirt and parasite removal and feather-oiling) Turkey Vultures typically spend two to three hours a day preening, mostly nibbling at the base of feathers, but also running their bill along the shaft of individual feathers from the base to the tip.
Typically in the morning they preen at their roost or in a communal post-roosting area on perches exposed to the sun before heading out to forage. Shortly before sunset they do the same in reverse, landing in an exposed pre-roosting perch site within half a mile of their roost site and engage in maintenance activities before bedding down at their roost site for the night.
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Fringed Polygala Flowering
I would like to dedicate this post to Jenepher Lingelbach, my very dear friend and giant contributor to the field of environmental education in Vermont. Thousands of people, both children and adults, benefitted from her enthusiastic and bountiful natural curiosity and her delight in sharing it with others. Jen’s influence will be felt for many generations to come.
Fringed Polygala (Polygala paucifolia) is one of those wildflowers that I am irresistibly drawn to photograph and post about almost every year. Also called Gaywings, this diminutive flower (about 1 ½ inches long) is a member of the Milkwort family, and produces compounds reputed to increase milk production in nursing mammals. The flaring wings and propeller-like. fringe on the flower’s tip give it the appearance of a small magenta airplane. When pollinators (mostly bumble bees) land on the fringe-tipped petal, the reproductive structures are exposed. In addition to the showy flowers that are insect-pollinated, there are also inconspicuous flowers that are borne underground and which self-fertilize without opening. (Thanks to Roger and Eleanor Shepard, and Sara and Warren Demont for photo op.)
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Barred Owl Parents Providing Fledglings With Food
Young Barred Owls are fed from the time they hatch (four to six weeks old) until late summer or early fall, months after they have fledged and long after they are capable of flight. When first out of the nest, the fledglings cannot fly, and thus are totally dependent upon their parents’ continued delivery of prey. The fledged young initially stay near one another and the nest site. The parents continue to feed them, and as the young become more mobile they slowly move away from the nest tree. Flight is attempted between the ages of 12 and 15 weeks. The first attempts are, as you would imagine, rather awkward, but as their wings strengthen, the young owls’ flying skills improve. Even so, the parents continue to feed them through the summer and often into the fall, when prey deliveries slow down and eventually cease, forcing the young to disperse. (Photo: Recently-fledged Barred Owl chick eyeing the Flying Squirrel its parent is delivering.)
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Wild Chervil Removal Tips
Should you wish to rid yourself or others of invasive Wild Chervil, a Naturally Curious reader, Susan Hand, generously shared this helpful information:
Wild chervil is not a strict biennial but monocarpic meaning that it flowers once then dies. The problem is that each root is capable of producing many offsets, lateral buds that do not die when the main root dies. New seedlings can take several years to reach blooming size.
The best way I have found to control or remove this plant is to dig it up being careful to get all the buds. The roots tend to be less than one foot deep but you do not need to get all of the root just the very top where the leaves join and the root and all the offsets, think carrot not dandelion.
I live in central Vermont and have been dealing with chervil for 19 years removing it from my 3.5 acre property and have for the most part succeeded. I have found if I remove all the blooming plants and as many of the smaller non blooming plants that I find the it does not spread but it can take up to five years to completely remove a large patch.
Wild Chervil Flowering
You can’t drive very far right now without seeing a sea of tiny, white flowers belonging to an invasive plant, Wild Chervil (Anthriscus sylvestris), crowding the shoulders of the road. A member of the carrot family, Wild Chervil leafs out early in the spring before most native plants and consequently shades them out and displaces them. It spreads aggressively and produces many seeds that are dispersed by birds, water and mowing (after the seeds have set).
Native to Europe, Wild Chervil was introduced in the early 1900’s to North America in wildflower seed mixes intended to reproduce the European countryside in gardens. Little did gardeners know that among these seeds was a plant that would outcompete native plant species and drastically reduce wildlife habitat. In addition to choking out native plants, Wild Chervil also is the host for a virus that infects carrots, parsnips, and celery.
Because it is a prolific seed-producer Wild Chervil can be challenging to eradicate. The best way to control it is to stop it from flowering and setting seed, but unless you mow early, every year, before its flower buds open, this isn’t a very effective method. Its up to six-foot-long taproot makes removing it by hand extremely difficult, but possible; however, this method also runs the risk of breaking off lateral buds at the top of its roots that can grow into new plants. Beware — Wild Chervil looks a lot like Poisonous Hemlock (Conium maculatum).
One of the few positive things to be said about Wild Chervil is that its flowers are a source of nectar for small bees, parasitic wasps, flies and beetles. Black Swallowtail larvae feed on the foliage. Many of these flowers are being visited now by thousands of flies in the Bibionidae family. Pull over the next time you see clouds of white smothering the edge of a road and look for these tiny, black flies. The males are the ones with the big eyes (pictured).
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Striped Maples Flowering
Striped Maple (Acer pensylvanicum), named after the vertical white streaks on its bark, is often associated with Moose and White-tailed Deer, both of which feed on its bark. In some places it goes by the name “Moosewood” for this very reason. The shape of its leaves give it another common name, “Goosefoot Maple.” In the spring when Striped Maples are nearly in full leaf, bright yellow bell-shaped flowers appear on long, pendulous strings, or racemes. (The flower stalks of the similar Mountain Maple also materialize after the leaves have matured, but these flower clusters are upright, held above the surrounding leaves.)
Striped Maples have the unusual ability to change sexes repeatedly over their lifetime (as does Jack-in-the-Pulpit), a phenomenon called gender diphasy. Among five study populations located in New Jersey, approximately one in four trees exhibited a change in the sex of its flowers between flowering seasons. The flowers of most Striped Maples are predominantly male. If changes occur in the canopy and new conditions seem favorable, a predominantly male tree can become predominantly female (and vice versa, if conditions deteriorate). Size, injury, and carbohydrate reserves are thought to impact the frequency and direction of gender change. Another unusual trait of Striped Maples is that the final sex of a flower is determined within one month of flowering, in contrast to most woody perennials which set buds the previous year.
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