The 114th Christmas Bird Count

Carolina Wrens by Dave Bonta

The Carolina wren pair that hung around the house in the winter of 2013-14

Last December I watched as day after day brought cold temperatures and more snow. We were expecting our son Dave’s English girlfriend, Rachel Rawlins, and her 14-year-old son, Alex, for the holidays, and Dave had already polished the sled runners.

Rachel, who lives in London, is interested in birds and arranged her schedule so she could be here for our Christmas Bird Count on December 21. It was the 114th CBC, as it’s fondly called, and is the longest running citizen science survey in the world.

Frank Chapman started the CBC back in 1900 to counter the competitive Christmas Side Hunt. On Christmas day folks chose sides, went out, and shot all the feathered and furred quarry they could find, and the team that killed the most won the competition. Chapman rounded up 17 birdwatchers from Pennsylvania to California, and suggested that they count birds instead of killing them. On that first count, five of the 25 CBCs took place in eastern Pennsylvania.

From that humble beginning, the CBC is now continent-wide with over 2300 count circles 15 miles in diameter. Ours is centered on a tiny crossroads in Sinking Valley called Culp. It includes our mountaintop property where we’ve been counting since 1979. For a long time I and one of our two birding sons—Steve or Mark—counted here. When they left home, I soldiered on alone, but a few years ago, Carl and Kurt Engstrom volunteered to cover the steep Sapsucker Ridge portion of our mountain while I covered the somewhat easier Laurel Ridge portion.

Recently, Steve and Mark moved back to the area, and Steve is now the CBC coordinator for the Juniata Valley Audubon Society count circle and is assisted by Mark. Determined to get total coverage of our circle, they have been going down to the valley to places that other members of our group are not able to count.

Rachel sunbathing on the Guest House porch

Rachel sunbathing on the Guest House porch

I figured Rachel and I would have a lovely slog through the snow, but after she and Alex had an invigorating time sledding on the 19th, they watched with us as the mountain turned from white to mostly brown under all night thaws and daytime temperatures in the low 50s Fahrenheit. Then rain and mist fell the evening before our CBC and into the early morning with dire predictions for the rest of the day.

The Engstroms set out by 8:00 a.m. after Carl reported four eastern bluebirds on our electric wires near the bluebird box and helped to count the meager number of feeder birds—a disappointing contrast to the huge numbers when we had seven inches of snow on the ground and temperatures had ranged in the low teens.

Undeterred by the weather, Rachel and I donned raincoats. I also carried an umbrella and kept my new “waterproof” binoculars underneath my raincoat, which did not make it easy to spot birds quickly. My so-called waterproof boots leaked as usual. Rachel, on the other hand, insisted in her British way that “layers of wool” would keep her warm and dry as did her waterproof boots and wool hat. Still, when the first deluge of rain hit us, like a cold tropical downpour, she didn’t object to sharing my umbrella through the worst of it.

The spruce grove in winter

The spruce grove in winter

Her job was to write down the bird species and numbers while I called out the identifications. At first she didn’t have much to do. We headed up to the spruce grove where I was certain we would find birds. But the birds hadn’t sought refuge there. We did instead, hoping for a cessation of the pounding rain. As we waited, we peered down into the valleys that were white with fog. At least we were above that. Those folks birding there might not fare too well. But we weren’t faring very well either, having neither seen nor heard any bird, not even on the heifer carcass staked out to attract golden eagles in front of a trail cam behind the grove.

On we sloshed to the Far Field. Still nothing.

“Are you game for a longer hike,” I asked Rachel.

Of course she was. As a British citizen, she was used to rain. Lots of rain.

We threaded our way through the trail-less woods beyond the Far Field and finally saw a downy woodpecker and northern cardinal and heard a black-capped chickadee or two.

Red-tailed hawk with vole

Red-tailed hawk with vole

From the Second Thicket, also empty of birds, we took a steep trail halfway down the mountain, stepped over a rivulet, and followed another trail through a hollow I long ago named Ruffed Grouse Hollow because I had once counted 40 ruffed grouse there on a CBC back in the early eighties. Not on this one, though. But we did find a couple of blue jays, a red-bellied woodpecker, and more cardinals and chickadees. And we heard a red-tailed hawk. Or did we? Blue jays are excellent mimics of red-tails.

“Put a question mark beside it,” I told Rachel.

All the while it rained, sometimes hard, sometimes not so hard. My shoes and socks were thoroughly soaked, but I walked fast enough that they felt reasonably warm.

A couple of times we questioned ourselves. What were a 73- and 52-year-old woman doing in this mad quest to count birds? Having fun, we assured ourselves over and over.

At last we reached the hunting lodge, and Rachel photographed the antlers hung on its back outside wall, especially one that held an old robin’s nest in its tines. After that, we took our first rest under the shelter of the porch and watched the rain. I had hoped that the hunters might have put some feeders of deer suet in their yard as they had the last time I had been there on a CBC. Then, I had been alone and in the midst of a snowstorm. But this time there was no suet or birds.

Maybe there would be birds in their autumn olive hedgerow or their cultivated fields. Nothing!

The antler nest (photo by Rachel Rawlins)

The antler nest (photo by Rachel Rawlins)

Back into the forest we went in search of the upper trail. And then, at 11:00 a.m., our luck changed. A red-tail flew over even as blue jays scolded.

“Count that red-tail,” I told Rachel. “It’s probably the same one we heard earlier.”

We saw a few more chickadees, downies, and cardinals. Then we plunged into an overgrown area in search of another trail heading back toward the Second Thicket. As I floundered around, Rachel said, “Look.” She pointed up at a cluster of black birches with fruiting catkins that were twittering with American goldfinches. I counted and re-counted and searched in vain for a pine siskin. After numerous counts, I settled on 29.

Just like that we were on a minor roll. Two golden-crowned kinglets answered my pishing and not Rachel’s trilling birdsong, which was her British equivalent of our pishing. I had been hoping for kinglets and was grateful.

“Maybe we’ll see a brown creeper,” I said. “It’s difficult to tell their call from a kinglet’s.”

“Look,” Rachel said once again, this time with considerable excitement in her voice, and she described the location of what resembled the Eurasian treecreeper. Sure enough, it was a brown creeper scuttling up a tree trunk like a tree-borne mouse.

Brown Creeper by Kelly Colgan Azar

Brown Creeper (photo by Kelly Colgan Azar [license])

That ended our short bird rally, although we did add still more chickadees, downies, cardinals, and three tufted titmice to our list, all birds we could have counted at our bird feeders. I did locate one hairy woodpecker in our forest, but after five hours and four miles of slogging through the rain, we had counted a mere 11 species. We also spotted one of the bluebirds Carl had seen earlier as we approached our yard, and with other species at our feeders—white-throated, song and American tree sparrows, mourning doves, slate-colored juncos, house finches, white-breasted nuthatches, and Carolina wrens—we had a grand total of 19 species.

Marcia at the Second Thicket, 2013 CBC (photo by Rachel Rawlins)

Marcia at the Second Thicket, 2013 CBC (photo by Rachel Rawlins)

Later, at the bird count dinner, no one had done much better, although Carl and Kurt had found one hermit thrush amid the grape tangles on Sapsucker Ridge and our sons Steve and Mark had spotted a rusty blackbird in a large flock of European starlings and brown-headed cowbirds down in the valley. Even though we had dedicated counters, we had one of the worse counts ever—only 43 species in all.

In other sections of Pennsylvania on other days counters did better—155 species statewide with Southern Lancaster County’s 102 species the best count in the state. Still, we know that as citizen scientists, according to the Audubon website, our counting helps protect species and their habitat and has “allowed researchers, conservation biologists, and other interested individuals to study the long-term health and status of bird populations across North America.” With the CBC and other bird counts, as well as other scientifically-based studies in whatever field a person might be interested in, we amateur naturalists can make a difference.


Photos by Dave Bonta except where indicated.

Year of the Sinking Valley Eagles

Bald eagle with fish by Ron Holmes-USFWS

Bald eagle holding a fish in its talons by Ron Holmes/USFWS (license)

I’m sitting on Alan’s Bench this breezy first day of November, watching for migrating raptors along our ridge top. Since we live on the westernmost ridge in the Ridge-and-Valley Province, I am up here most breezy autumn days.

Suddenly, a large bird flies past above Sapsucker Ridge. It’s a mature bald eagle.

The next day I’m at the same place, but it’s mid-afternoon instead of late morning. Another mature bald eagle flies high and slowly above Sapsucker Ridge. Two bald eagles in as many days seem like a good omen. I wonder if they are migrating or local birds.

Then, on the 30th of January, my husband Bruce and I, along with an enthusiastic young birder, Michael David, who is working on his year-long, Blair County bird list, set out on our Winter Raptor Survey in Sinking Valley. Our mountain, locally known as Brush Mountain, almost entirely encircles this rural valley. Partly farmed by Amish and mostly by English, its rolling fields are open to the winds of January.

We’ve picked a cold (five degrees) but clear day for our count. Ever since Greg Grove started this count, back in 2001, we’ve driven the same route that Bruce mapped out after studying the back roads that wander through Sinking Valley.

It’s a slow day at first for raptors, but Michael points out American robins feeding on staghorn sumac berries and an American tree sparrow amid the dried grasses beside the road. I later spot a pileated woodpecker in a small patch of woodland. We are looking for American kestrels on telephone wires, but all we turn up are mourning doves. On a large farm field in the middle of the valley, we count 26 horned larks so close to the road that we see every marking on them.

Rusty blackbird by Nicole Beaulac

Rusty blackbird by Nicole Beaulac (license)

Near a stream next to a tree I notice a suspicious lump. It turns out to be a seated great blue heron. Just as we are musing over that strange sight, a golden eagle flies overhead. But mostly it’s a day for red-tailed hawks. On every tree line across a field are perched from one to a handful—26 by the end of our 32-mile, three hour, slow ride.

At one farm we stop to look at a large flock of brown-headed cowbirds because Michael thinks there may be a rusty blackbird among them. He gets out of the car and walks down the road to scan the flock which keeps flying ahead of him. I follow half-heartedly, knowing I’m not going to be able to pick out a rusty from the throng of cowbirds high in the trees.

Instead, I notice a huge tree far across a field. In it sits a large bird that looks as if it has a white head. It’s a mature bald eagle. Sitting on a branch above it is a second mature bald eagle. I’m excited and call Bruce, who’s been sitting patiently in the car, to bring our spotting scope for a better view. After several years of seeing one mature wintering bird eagle in the valley, I wonder if they are a pair and nesting somewhere nearby.

Back in 2011, when an Amish youngster who watches birds in his spare time first told us of a wintering bald eagle during our Winter Raptor Survey, I speculated about possible breeding. But I thought that because there was no river or lake nearby, bald eagles wouldn’t nest in a place without fish to eat.

A hard winter and late spring keeps me from returning to the valley until mid-May in search of fresh rhubarb and asparagus from Amish farmers. That’s when I learn that a pair of bald eagles is nesting on the other end of our mountain. My Amish friend has spent time watching them from afar across a steep, wooded ravine on State Gamelands #166.

Bald eagle family

Bald eagle family at John Heinz National Wildlife Refuge in Philadelphia by Bill Buchanan/USFWS (license)

They have two eaglets, he tells me, and once he saw a parent feed them a gray squirrel.

“It took them exactly 20 minutes to eat that squirrel,” he says.

Returning back across the valley on my usual circuitous route, I pass the tree where I had seen the eagles perching in January. One eagle sits in it. Later, when I take out maps and do the calculations, I realize that the tree is about one mile, as the crow flies, from the nest. I assume it is a favorite hunting area and learn from another resident that he had seen an eagle fly overhead with a rabbit in its talons.

According to Patti Barber, a biologist with the Game Commission’s Endangered and Nongame Bird Section, bald eagles are opportunists. In the winter they often live on carrion, and in Alaska even go into dumpsters. On the other hand, friends of mine who monitored three bald eagle nests in a nearby county saw them feed nothing but fish to the young, although they observed only four feedings. But once, in the middle of a road, they saw a bald eagle eating a dead woodchuck.

All of their nests were in very large white pine trees. Two were on steeply forested ridges and the third on a farm fence row. One was near a river, another near a lake, and the third near a small, wooded stream.

My Amish friend is amazed at the size of the nest.

“I once heard it described as like a Volkswagen upside down in a tree,” Barber says. “It’s the biggest nest of any bird in Pennsylvania.” And they continue to add to the nesting material every year they use it.

Bald eagle by  e_monk

Bald eagle by e_monk (licence)

The number of bald eagle nests in the state keeps climbing. When I contact Justin Vreeland, Wildlife Supervisor of the Game Commission’s South Central Region, he tells me that 15 new nests have been reported in his 12-county region this year, and that our nest is the second one for Blair County. The other one is on a heavily forested slope above the Frankstown Branch of the Juniata River near Water Street.

Altogether, Vreeland knows of 70 nests in his region, but when he started working here in 2005, only 12 had been reported.

The number of bald eagle nests in the state continues to climb, Barber says. The 2014 mid-year inventory of nests was 254 in 59 of Pennsylvania’s 67 counties. But as Game Commission Director R. Matthew Hough said at that time, “The all-time high numbers illustrate Pennsylvania’s bald eagle population is better than ever. But these are only ones we know about. There are more.” And our nest is one of them.

At some point the state will reach a saturation number, but we’re nowhere near that, Barber tells me. For example, along the Susquehanna River in one area are two nests four miles apart. Then another pair nested between the two nests.

I have yet to see the Sinking Valley nest. My Amish friend tells me it’s a steep climb. But before I knew about this nest, we took our granddaughter Elanor to the Nature Center at Bald Eagle State Park in mid-April to watch a nest in a white pine tree halfway up a wooded mountain and across an arm of the lake from the Center. We set up our scope and had an excellent view of one parent sitting on the nest while the other flew low above the water in search of fish.

At a time when so much of the news about the natural world is dismal, the return of the bald eagle in Pennsylvania from three nests in 1983 to 254 and more to be counted in 2014 is a heartening story. If anyone would have told me when we moved here in 1971 that bald eagles would be nesting on our mountain, I wouldn’t have believed them.

Gamelands Tour

view of SGL#108

view of SGL #108 on last October’s tour (all photos in this post by Bruce Bonta)

I’ve always preferred to walk rather than drive through the fields and forests of Pennsylvania. Still, I was tempted last October by a driving tour in nearby State Gamelands #108 and persuaded my husband, Bruce, to accompany me. It was a lovely autumn day when we found our way to a gamelands access road in Cambria County, not far from Prince Gallitzin State Park, and lined up behind a couple dozen cars.

At the gate we were greeted and handed several information sheets and a map that designated stops along our 7.5 mile, self-guided, one-way tour. We also tested our outdoor knowledge along the route by guessing the identity of marked trees and wildlife mounts including fisher, mink, ring-necked pheasant, black bear, barred owl, and bald eagle.

But we especially enjoyed stopping and talking to the agency personnel. I noticed the incredible abundance of pokeweed and staghorn sumac along the road and was assured by Joe McAnulty, one of the Food and Cover crew members, that they purposely widen roadsides to let in the sun, which encourages the growth of wildlife food, for example, the pokeweed and sumac, as well as blackberries and sassafras. They also allow wild grapevines to grow.

“We manage for animals,” McAnulty assured us.

With the help of special machines, also on display, they create wildlife openings in the forest to support native plants, legumes, or annual grains. They had just finished a prescribed 87-acre burn to encourage scrub oak to grow, which almost always produces a large crop of acorns every fall. In addition to the 23,086 acres of SGL#108, four workers are responsible for managing the 23,000 acres of four other nearby gamelands, McAnulty told me.

At another stop, we talked to a couple law enforcement personnel who showed us the amazing array of tools they need to foil lawbreakers. A deer exclosure, a couple shelterwood cuts, and a vernal pond were also highlighted on our route, but I was particularly eager to see a rehabilitated strip-mined area, which had been converted to a small-game and grassland nesting bird habitat.

Samara Trusso

Game Commission biologist Samara Trusso with short-eared owl habitat

There I talked to biologist Samara Trusso who told me that short-eared owls winter on the grasslands in February and March. This is important because there is a chance that they might breed there too, although so far no breeding has been recorded. The short-eared owl is one of Pennsylvania’s rarest breeding birds and is listed as endangered in the state. Pennsylvania is the farthest south this mostly circumpolar species nests and then only rarely.

Trusso also said that the rehabilitated strip-mined area provides grassy habitat for grassland birds because the sites have acidic, nutrient-poor soils that produce grasses and legumes and have a slower rate of plant succession. But she assured me that the 40% shrub component of this large acreage has no impact on grassland breeding birds that have been documented for the site—grasshopper, Savannah, and Henslow’s sparrows, northern harriers, eastern meadowlarks and bobolinks.

That was our last stop, but we drove a couple more miles through the grasslands.

“This looks like harrier country,” I commented to Bruce just as a northern harrier flew up and over the grasslands.

Then, as the area grew more shrubby and medium-sized conifers, including larch and red pine, as well as deciduous trees provided more cover; two cock ring-necked pheasants strolled out in front of our car and fought. It seemed a fitting end to what had been a worthwhile tour and one that has been given every fall except for a year when it snowed.

wildlife opening on SGL #108

wildlife opening on SGL #108

To my surprise, we emerged at a gate on State Route 865 near Blandburg at the top of the Allegheny Front, a mere 26 miles from our home. I immediately made plans to return and see the breeding grassland bird species. Snow in late winter foiled my attempts to hike in and see the wintering short-eared owls, but one lovely Sunday in late June, hoping to see the documented grassland breeding birds, we parked at the Blandburg entrance and hiked back the way we had driven on the auto tour. Bruce was armed with gameland maps he had gotten off the web and had plotted out a circular route for us.

The first couple miles, amid the conifers and deciduous trees, we heard common yellowthroats, field sparrows, and song sparrows. But then, alternating with the singing of song sparrows, I heard the dreamy, lisping tsit-tsit-tsit-teee-taay of a Savannah sparrow. He remained hidden in the shrubs, but his song was unmistakable. A few minutes later, I heard the thin, dry buzzy tumble of notes of a grasshopper sparrow. He too remained out of sight in the shrubs.

Sassafras on SGL #108 (seen on the October tour)

sassafras on SGL #108 (seen on the October tour)

We passed a large field white with daisies and heard a common yellowthroat sing both his familiar “witchity” song in addition to one of the less common variations of his song. A sudden breeze carried turkey vultures and a red-tailed hawk past. The hawk was then sent on its way by several red-winged blackbirds.

Eventually we reached the largest open section of grassland. The sun was hot and bright, and already it was late morning. I began to wonder if I would see any of the grassland birds. And then our luck changed. A Henslow’s sparrow sat in a dead shrub near the road and sang his quiet tsi-lick hiccup of a song. He was so close that we could watch him open his beak and sing over and over. I noted his short tail, flat, olive-colored head, big pale bill, finely striped breast, and reddish wings through my binoculars before he flew away.

Henslow’s sparrows are found mostly in the western part of Pennsylvania on rehabilitated strip-mined areas because they like a buildup of dead litter and perennial stalks, according to Andrew M. Wilson in the Second Atlas of Breeding Birds in Pennsylvania. The State Wildlife Action Plan lists the Henslow’s sparrow as a species of High Concern because we have about nine percent of the world population. This native of the tallgrass prairie has lost much of its habitat to agriculture in the Midwest.

I was especially pleased to see favorites of mine—bobolinks that rose from a couple shrubs beside the road, the three males scolding, their buff-yellow napes and white wingbars a striking contrast to their black bodies. Then a brown-backed female with a brown stripe on her head joined the agitated males.

timber rattlesnake coiled to strike

the timber rattler that Bruce insisted on photographing

At the same time I noticed a timber rattlesnake crossing the gravel road in front of us. Bruce rushed up to snap several photos before it slid off into the field, causing still more anxiety on the part of the bobolinks. We watched them for as long as we could as we continued our hike past the grassland. Just as I was lamenting that I hadn’t heard or seen an eastern meadowlark, a male flew up from the middle of the field, flashing his yellow chest and throat, the latter with its black V necklace. Both the bobolinks and the eastern meadowlarks prefer to nest in hayfields, the bobolinks particularly in fields at 2,000 feet on the Allegheny Plateau. But early mowing has led to the demise of many young birds and so this high-altitude unmowed field is of great importance to those species.

From the top of the open grassland, we had a view in every direction encircled by mountains and forest. Despite the dry day, it was hot in the grassland, and gratefully we descended a trail down to a series of forested ponds. We sat on rocks beside one pond to eat our lunch. At another pond a female wood duck with her ducklings swam into cattail cover when they saw us. Singing woodland songbirds included wood and hermit thrushes, black-and-white and black-throated green warblers, ovenbirds, scarlet tanagers, cedar waxwings and indigo buntings.

Looking down on still another large pond from a small planting of red pines, we flushed a great blue heron. A ruffed grouse with half-grown young flew from the edge of the woods.

We spotted the first monarch butterfly of the season nectaring on yellow hawkweed, but it was near large areas of common and poke milkweeds growing beside the access road. That was where it would no doubt lay its eggs because monarch caterpillars only eat the leaves of milkweed species.

The last half-mile of our six-and-a-half mile hike was along State Route 865 where we saw and heard our first sign of people since we had parked our car. We were impressed by the remote peace and lack of even one piece of trash on this section of the gamelands. It was as far from the madding crowd as any place near our home—a prairie on a mountaintop where increasingly rare grassland birds thrive.

White-footed Mice

White-footed mouse from Squirrels and Other Fur-Bearers

Illustration from Squirrels and Other Fur-Bearers by John Burroughs (1909)

“I think mice are rather nice.” So began the children’s poem by Rose Amy Fyleman that I read to my three sons when they were young.

Fyleman was an English writer who lived in earlier times (1877-1957) and her mice were not the primary hosts for the larvae and nymphs of black-legged (Lyme disease) ticks or the possible carriers of hantavirus. Unfortunately, our winsome, large-eyed, big-eared white-footed mice are. They can be covered with the larvae and nymphs of black-legged ticks and build up huge concentrations of the Lyme disease bacteria Borrelia burgdorferi, which doesn’t sicken them, and thus remain the principal reservoir for the disease.

They also enjoy life in our old farmhouse, and we are compelled to keep traps laced with peanut butter especially in early autumn when they are seeking warm winter homes. Live-trapping and moving them are not an option even if we wanted to. The late, great mammalogist William J. Hamilton, Jr. once live-trapped and marked white-footed mice and released them a mile away from their home territory. A few days later they were back, exhibiting an amazing homing ability.

In addition, they know their home ranges of approximately one-fifth of an acre so well that they can quickly find hiding places whenever they are needed.

White-footed mice in an old bluebird box by Mark Lethaby

White-footed mice in an old bluebird box by Mark Lethaby (license)

But as Hamilton once wrote about the white-footed mouse, “It often takes up residence in houses; the first evidence of its presence may be a boot half filled with cherry pits or hickory nuts.” In our house, I find sunflower seed stashes not only in old boots but stuffed under the cushions of our sofas and chairs. And occasionally I’ve uncovered shredded sweaters or shirts balled up into nests on some forgotten closet shelf or in an old bureau drawer.

However, most white-footed mice find homes outdoors in abandoned squirrel, woodchuck, or bird nests, bird nest boxes, tree cavities, half-rotten stumps, rock piles or even in a ball of leaves underground. Recently, researchers have noted that they especially like the humid conditions under the rapidly expanding invasive shrub Japanese barberry, which is also favored by black-legged ticks, still another connection with Lyme disease and white-footed mice.

White-footed mice use their long tails as props and balancing organs, to climb trees, although they are not as adept as their longer tailed congener’s deer mice. White-footed mice (Peromyscus leucopus) and woodland deer mice (P. maniculatus) look alike, and often live in the same habitat in our Appalachian forests. The length of their tails can sometimes be their distinguishing characteristic because the tails of white-footed mice are slightly less than half the total length of their bodies while the eastern woodland deer mice have tails more than half their total length. But the best way to tell them apart is by comparing their skulls. Since I’m not inclined to measure their tails or study their skulls, perhaps some of the mice in our home are deer mice because they too can create havoc inside homes and camps and are carriers of hantavirus, although so far they’ve not been indicted as primary hosts for black-legged ticks.

Both species of mice are abundant over a wide range of North America, but white-footed mice have drastically increased their distribution over the last few decades and now are found in the eastern two-thirds of the United States except for Florida, as far west as portions of Wyoming, Colorado, and eastern Arizona, south through eastern Central America and north in Ontario, Quebec, southern Nova Scotia, and even Labrador.

White-footed mouse by Patrick Coin

White-footed mouse by Patrick Coin (license)

Back in the 1980s, J.O. Wolff did extensive studies of both white-footed mice and deer mice in the Appalachians of southern Virginia and found that female white-footed mice lived in separate home ranges while males had ranges overlapping one or more females with which they mated. It seems as if white-footed mice are usually polygamous, but can also be monogamous, and even in at least one known case polyandrous. These choices may protect their mothers and their young because males can recognize their mates and children and will not kill them. They even often help raise their offspring, although females do most of the work.

Mating begins in early March and continues through late October in Pennsylvania. Their gestation period is usually 23 days unless a female is still nursing a previous litter. Then gestation can be anywhere from five to 14 more days. Most litters contain four or five young but can be from two to eight.

Born tiny and naked, they develop rapidly, and at three weeks of age they are able to leave their nest, although if they are threatened they can leave at 16 days. Previously, if their mother is disturbed while nursing, she runs from the nest with her young clinging to her teats and sometimes falling off as she heads for the nearest hiding place.

These young can breed as early as 46 days of age, but most are two months or 60 days old before they do. Still, it is easy to see how many would survive if they did not have many predators such as skunks, mink, weasels, raccoons, foxes, coyotes, bobcats, black bears, and black rat snakes.

These “most abundant and ubiquitous rodents in Pennsylvania,” according to mammalogist Joseph F. Merritt, also have catholic food tastes, eating whatever fruits, seeds, and small creatures are available. A short list includes various grass seeds, raspberry seeds, shadberries, the fruits of viburnum species, hickory nuts, basswood seeds, and conifer seeds, and in the summer they add meat to their diets in the form of caterpillars, ground beetles, snails, centipedes, occasional small birds, and even other small mammals including young white-footed mice. But their favorite foods appear to be pitted wild black cherry seeds, acorns, and the seeds of jewelweed. The latter taste like walnuts and have turquoise-blue endosperms that turn their stomach contents turquoise-colored in late summer.

northern red oak (Quercus rubra) acorns by free photos & art

northern red oak (Quercus rubra) acorns by free photos & art (license)

On a study of the impact of small mammals on northern red oak regeneration by Colleen A. DeLong and Richard H.Yahner from October 1989 until December 1990 in Huntingdon County, Pennsylvania, they attributed most red oak acorn loss to white-footed mice from 67% to 88% in autumn and 94% to 100% in spring in a section of mature forest where they had planted 400 red oak acorns. Certainly, we’ve had fewer mice in our traps lately, and it may be because we haven’t had a good acorn crop in three years. In fact, many wild fruit and nut crops were sparse or nonexistent in 2013, including wild black cherries.

But by mid-autumn white-footed mice have collected caches of food to get them through the winter. Hamilton discovered that they are also fond of storing clover seed and beech seeds, and once found almost a peck of beechnuts they had stashed in a beech tree cavity in New York State.

Here in Pennsylvania, some white-footed mice have periods of torpor from late December until early February, but most remain active. They stay warm by nesting with other white-footed mice and/or deer mice huddled in tree cavities or by nesting underground.

During all seasons of the year, though, in our home, “they run about the house at night; they nibble things they shouldn’t touch, and no one seems to like them much,” as the poet Fyleman wrote. She may have thought mice were nice, but despite their beguiling appearance, I think they are an attractive nuisance.