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Grizzly bears, black bears, wolves, coyotes, cougars/ mountain lions,bobcats, wolverines, lynx, foxes, fishers and martens are the suite of carnivores that originally inhabited North America after the Pleistocene extinctions. This site invites research, commentary, point/counterpoint on that suite of native animals (predator and prey) that inhabited The Americas circa 1500-at the initial point of European exploration and subsequent colonization. Landscape ecology, journal accounts of explorers and frontiersmen, genetic evaluations of museum animals, peer reviewed 20th and 21st century research on various aspects of our "Wild America" as well as subjective commentary from expert and layman alike. All of the above being revealed and discussed with the underlying goal of one day seeing our Continent rewilded.....Where big enough swaths of open space exist with connective corridors to other large forest, meadow, mountain, valley, prairie, desert and chaparral wildlands.....Thereby enabling all of our historic fauna, including man, to live in a sustainable and healthy environment. - Blogger Rick

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Thursday, August 4, 2016

"As with many rodents, Red Squirrel populations rise and fall based on the mast(nuts and seeds) that’s available"...........Roughly half the size of the Gray Squirrel, the Red Squirrel is found from the Tundra tree line of North America south into the northern USA, ranging down both the Appalachians and Rocky Mountains......A lover of Conifer dominated forests, it is also at home in mixed and deciduous woodlands................"In a year after a big cone crop, a favorite winter food,, their population booms"........, "In years after a "mast-failure, their population plummets".............. "Red squirrels typically have two litters in a summer, important for a species that is prey for weasels, coyotes, and various raptors.......................Their own dietary menu consists of fruits, fungi, insects, adult birds and their nestlings and eggs.............The Squirrels put a damper on bird populations when they come off a heavy mast year and are almost a non-factor on bird populations when they come off of a lean mast year.................

Driving a Midden

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The first red squirrel appeared at about 50 mph. It climbed up over my headrest and landed in my lap. I don’t recall the next few seconds very clearly, but according to my 5-year-old daughter Lucy, I yelled something along the lines of, “oo squirrel. oo oo. squirrel squirrel.”
What I do remember is concentrating on finding a safe place to pull over, and my surprise that the squirrel remained in my lap for the duration. It had a warm, soft weight. Puppy-like. I brought the car to a stop by some woods and pushed the button to the passenger side window. The squirrel came out of stasis, ricocheted off the steering wheel, and launched itself into the bushes.
And that, I thought, was the end of the anecdote. No harm done, and a cautionary tale about why it’s unwise to leave the sun roof open in squirrel country.  
Alas, the sun roof was not the problem. Squirrels are still getting in my car, and I don’t know how. What I assumed was a one time occurrence, I now see as an opening volley. This is war, and the stakes are existential: is my car a car, or am I driving a midden?
When I turn the ignition key, I brace for rodent alarm calls. Last week, I found a hemlock cone wedged between the console and my seat. Lucy has regaled her friends, and their parents, and random people we encounter in awkward retail settings, about her mother’s wonderful, magical squirrel-inhabited car and the happy day when a cute little fuzzy friend perched on her head.
There is scat. It almost always appears on the dashboard, just above the radio where I’m sure to see it. And no, I don’t think this placement is a coincidence.
Driving a Midden Image
There are photos. My husband set up a game camera in the back seat and acquired a number of action shots and contemplative poses. He attached a “best of” selection to an email, which he sent to me when he knew we’d be out of communication for a few hours. In the email, he offered a carefully worded suggestion that perhaps it was time to reduce foraging opportunities.
This advice was a little hard to take from the family’s Johnny donut crumb, and also a little impractical in a vehicle that is daily employed to transport two very young children. Still, he had a point. I vacuumed out the car, and devoted a couple hours to shampooing the interior. This made no difference.
I showed one of the car-cam photos to Steve Parren, Wildlife Diversity Program Manager at Vermont Fish & Wildlife. In his professional opinion, the squirrel “looked quite content.”
Parren also provided some background on red squirrel population dynamics and feeding behavior. Some quick facts: as with many rodents, red squirrel populations rise and fall based on the mast that’s available. They are especially dependent on pines and other conifers for winter food, so in a year after a big cone crop, their population booms. Red squirrels typically have two litters in a summer, which is just as well for the species; there’s a long list of creatures that eat them, from weasels to birds of prey.
And likewise, during the warm months, they take an anything-goes approach to where they get their calories. Fruit and fungi are common foods – they’ll sometimes cache these in a notch of a tree to dry and store for future consumption. Insects, eggs, and baby birds are also on the menu.
They may even consume adult birds. Parren described the case of a horrified bird watcher who witnessed a red squirrel snatch a chickadee right off the feeder. In general, he said, people are taken aback by carnivorous squirrels, which he described as “cute little creatures with a dark side.”
I also spoke with Steve Faccio, Conservation Biologist at the Vermont Center for Ecostudies (VCE), and asked how squirrel populations may affect nesting success for birds. Faccio said that at high elevations, there’s a distinct pattern between balsam fir cone production and red squirrel nest predation. Balsam firs – the dominant conifer up on our mountains – typically produce cones in synchronized biannual cycles. In the winter of a cone production year, squirrels thrive on well-stocked middens, and are present in high numbers the next spring. Faccio described videotapes of red squirrels sitting in nests, cracking open one egg after the other and lapping up their contents. (In the case of eating fledglings, the tactic is more grab and go. The squirrel seizes its prey and carries it out of the nest).
Then the next winter comes, cones aren’t available, and the squirrels are pretty much absent from the habitat the next spring. High elevation nesting birds get a break from red squirrel predation.
What is not well understood, said Faccio, is squirrel dispersal in low cone years. He expects that squirrels respond to the low food conditions by moving downslope, but the pattern of their movements is a topic that merits more study.
It turns out this is one of those years when there aren’t many red squirrels high on the mountains. So assuming they didn’t all just die of starvation or other creatures eating them – where did they go? I’m working on my own idea about this. I call it the Toyota hypothesis

Red Squirrel

(Tamiasciurus hudsonicus)

from: Saunders, D. A. 1988. Adirondack Mammals. State University of New York, College of Environmental Science and Forestry. 216pp.
Order: Rodentia
Family: Sciuridae
Description: This, the Adjidaumo of Longfellow’s celebrated poem Hiawatha, is the voice of the Adirondack’s brooding forests. The red squirrel’s appearance varies seasonally. The paler, reddish to olive gray coat of summer includes a black line along each side, and creamy white or buffy underparts. In the winter, reddish brown ear tufts and a bright rusty red stripe along the back develop while the black lines along the sides are usually faint or absent, and the underparts become silvery gray or white. A buffy or white eye-ring is present in all seasons. This common tree squirrel of the Adirondacks is about half the size of a gray squirrel, and is stouter, longer, and lacks the dorsal stripes of the eastern chipmunk. The red squirrel is about 30 cm (12 in) long, the tail accounting for nearly a third of the total length. Large adults weigh 240 g (8.4 oz).
Range and Habitat: The range of the red squirrel is from the tree line of North America south into the northern U.S., the Northeast, and continuing in the Rocky and Appalachian Mountains. Although primarily an inhabitant of coniferous and mixed forests, it may also reside in deciduous forests, especially the northern hardwoods. In the Adirondacks, the red squirrel is associated with the coniferous and mixed forests at all elevations.
Within these habitats, red squirrels build nests 3-18 m (10-60 ft) above the ground inside a natural tree cavity, abandoned woodpecker nest, or on a branch. Exposed nests are usually near the trunk on a large branch, occasionally in a witch’s-broom.
The nest is 20-50 cm (10-20 in) in diameter, and made of a coarse outer layer of bark or litter from the forest floor, and an inner layer of finely shredded bark, often from yellow birch or white cedar. A single entrance, opposite the side nearest the trunk of exposed nests, leads to the inner chamber. Red squirrels may also build nests in an underground chamber which they excavate. These chambers are approximately 23 cm (9 in) long, 10-13 cm (4-5 in) in diameter, and 30 cm (12 in) beneath the surface of the ground. Buildings, logs, stumps, log piles, bird houses, and rock walls are other locations.
Food and Feeding Behavior: The seeds of conifer cones form the mainstay of diet of this rodent. To get these cones, the red squirrel clambers about the branches of balsam fir, larch, white cedar, pines, and spruces, cutting green cones. A dozen or more may fall to the ground before the squirrel descends to retrieve and bury the cones in one or several chambers in its territory. By cutting only green cones, the red squirrel ensures that the seeds are still present. Middens mark the presence of the red squirrel. The term midden in the case of this species refers to both food cache, and to the debris that accumulates over months and even years from stripping cones on a nearby log, branch, or stump.
Other important foods include the buds, inner bark, sap, nuts and seeds of deciduous trees and shrubs. Fungi, even some species of the toxic genus Amonita, and fleshy fruits may form a large part of the summer diet with the surplus carried aloft to dry among twigs or wedged between branches. Red squirrels also consume invertebrates such as insects, and some vertebrates, for example, small mammals birds, and birds’ eggs.
Remnants from a red squirrel meal
Juvenile red squirrel peeking from
Activity and Movement: The red squirrel is diurnal and arboreal, its activities in the trees often unnoticed because of the dense foliage. During the warmest days of mid-summer, activity peaks at twilight. Midday activity is typical of cold winter days when red squirrels leave the protection of their nests to visit food stores, sometimes digging elaborate snow tunnels to reach there stockpiles.
Red squirrels navigate trees with ease, running up and down trunks, or along branches, bounding up to 2.4 m (8 ft) through the air from one branch to another to reach different trees, occasionally falling to the ground unscathed. On the ground, they walk or run, and when alarmed, they may attain speeds of 22.5 km/hr (14 mph) for short distances.
Reproduction: The courtship which precedes mating between a pair of red squirrels is brief and relatively unritualized. One to 10 males may pursue a female during her one day estrous period, the dominant male eventually approaching the female while giving quiet vocalizations, and then mounting her. Copulation is brief, but may recur several times before the female becomes aggressive. Some females may mate again with different males. After a gestation period of 36-40 days, the female bears her young in a nest of shredded bark and leaves. A typical litter contains 3-5 young, but can vary from 1-8. Blind, naked, and pink at birth, the young develop slowly, their eyes not opening until 27 days of age. By day 30, they are fully furred, and they begin to venture from the nest. They are weaned soon after. By 9-11 weeks of age, they establish their own territories.
Some females produce litters in both April and August, but others produce just one litter annually during one of these periods. Sexual maturation of the young occurs the winter following their birth. Red squirrels may live 10 years, although 3-5 years is the average life span for adults.
Predators: Raccoons, foxes, bobcats, coyotes, weasels, minks, fishers, hawks, owls, and martens are predators of the red squirrel.
Social Behavior:
  • Social System - Pugnacious, fearless, timid, saucy, curious, and loquacious are terms early naturalists used to characterize the red squirrel. While more descriptive terms are used today, these older words do capture the personality of the red squirrel. The red squirrel is sedentary, solitary, and promiscuous, and defends a territory of 0.4-3.2 ha (1-8 acres). During breeding season, males wander from their territories. While in estrous, a female permits their encroachment on her territory.
  • Communication - A resident red squirrel gives a long, rattling buzz, the notes slowing and fading, when another red squirrel enters its territory. At the highest intensity, tail-jerking and foot stamping accompany the call. Neighboring red squirrels may respond with similar calls, producing a chorus. This call functions to advertise an occupied territory and to increase the distance between individuals. A slowly repeated “whuuk” occurs as an alarm call. Motor patterns, posturing, and chemical signals convey information among red squirrels, but are not as specialized as vocalizations, a consequence of the lifestyle amidst concealing conifer.

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