Butcher Bird

A week of light snow, followed by sleet and freezing rain last January, turned our mountain into an ice rink and penned me inside until it warmed above freezing. That occurred on January 25 when it was 36 degrees and dripping rain at dawn.

A northern shrike on an electric wire beyond our barn (Photo by Mark Bonta)

A northern shrike on an electric wire beyond our barn (Photo by Mark Bonta)

Late that afternoon our son, Mark, who was living in our guesthouse, called to tell me there was a northern shrike perched on the electric wire beyond our barn. I pulled on my boots and jacket and walked slowly downhill to where Mark was standing between the barn and the shed. There I had an excellent view of the shrike, which kept turning its head to look at us and twitching its tail. Mark then circled around the barn to Butterfly Loop, hoping to take a closer photograph of the bird.

But the shrike flew down past me and into the top of a small tree near the guesthouse. Next it flew into the tallest front yard black locust tree. Finally, the shrike flew away. I was thrilled because that was the first time I had ever seen one.

There was no trace of brown on the bird, which meant that it was an adult northern shrike. It looked like a brighter-colored version of a northern mockingbird with a gray head and back, black wings and a tail marked with white, a white throat, breast and belly, but it also had a distinctive black mask.

Early the following morning Mark searched for the shrike and found no trace of it. However, later in the morning, as I descended the Amphitheater Trail in First Field, I spotted the shrike at the top of a black walnut tree near the shed. But it flew off. Then, as I approached the house, it suddenly flew over the roof and away. A few minutes later Mark located it across First Field at the top of a catalpa tree.

A northern shrike with its prey (Photo by Kelly Colgan Azar on Flickr, Creative Commons license)

A northern shrike with its prey (Photo by Kelly Colgan Azar on Flickr, Creative Commons license)

The shrike had been using the wire and tree perches to hunt for prey. Called a “butcher bird” because it not only has a hook-tipped bill with which it kills prey with a bite to its neck but often it impales it on thorns or barbed wire or shoves it into forked branches for later consumption. Ten-inch northern shrikes will kill birds larger than themselves, for instance, 12-inch mourning doves and 11-inch blue jays. In the winter they are also looking for meadow voles and white-footed mice to consume.

Although we kept looking, we saw no further sign of the shrike until February 9. It was 31 degrees at dawn and the ground was covered with a light snow that had fallen overnight. I headed out at 9 am, bound for Greenbrier Trail. As I ambled along Butterfly Loop toward Margaret’s Woods, I paused to admire the snow-covered landscape. A bird, its tail twitching, was perched on top of the same catalpa tree across First Field where Mark had last seen the shrike. At first I thought it was a crow but through my binoculars I could see that the northern shrike was making a return visit after its first visit two weeks before. As I neared the tree it flew away.

I resumed my walk but coming back across First Field two hours later, a spot of white in a black locust tree at the base of Sapsucker Ridge turned out to be the shrike. From there it flew to the top of a pear tree and then into a black walnut sapling at the edge of First Field close to where I was standing. Lastly, it flew behind the barn and back across the field to the catalpa tree.

I had been trying to contact Mark since my early morning sighting, but he had been off birding at the Far Field. Finally, both he and his brother Dave joined me, and we all had a look at it back in the small locust tree at the base of Sapsucker Ridge. And that was our last glimpse of the elusive boreal songbird. It had enlivened what had been a dull winter for birds since neither northern finches nor red-breasted nuthatches had irrupted from the north.

A northern shrike in British Columbia (Photo by Murray Foubister on Flickr, Creative Commons license)

A northern shrike in British Columbia (Photo by Murray Foubister on Flickr, Creative Commons license)

Northern shrikes are also an irruptive songbird that breeds in the shrubby north from Labrador and Quebec to western Alaska. Many of them migrate south to southern Canada and the northern United States during late autumn and early winter. Every three to six years their numbers peak, and northern shrikes can be found as far south in the eastern United States as Virginia.

Most years, five to ten northern shrikes are observed in Pennsylvania especially in the northwest. They prefer to hunt on open brushy fields, which describes our First Field, as well as farm fields and strip mines. They may also hang out near bird-feeding stations and catch songbirds.

Last winter only four northern shrikes were found during the statewide Christmas Bird Count (CBC) and three during the 2020 Winter Raptor Survey (WRS), which is held from mid-January until mid-February. All three of the WRS shrikes were reported from northwest counties—Warren, Clarion, and Butler. The closest reported shrike to us was one at Bald Eagle State Park during the CBC. Irruptive northern shrikes have not been well-studied but sometimes they hold large territories of several hundred acres. Otherwise, they wander widely.

The largest recorded irruption of northern shrikes throughout North America happened in 1995-96, but in Pennsylvania it was the third largest with 50 shrikes in 29 counties. The largest in our state occurred the winter of 1999-2000 when there were 137 shrikes in 47 counties.

A northern shrike at the John Heinz NWR, Philadelphia (Photo by Brian Henderson on Flickr, Creative Commons license)

A northern shrike at the John Heinz NWR, Philadelphia (Photo by Brian Henderson on Flickr, Creative Commons license)

Paul Hess wrote a comprehensive article for Pennsylvania Birds on this irruption. It began with the sighting of two northern shrikes on October 24 in Erie County, which Hess described as “the state’s most regular shrike location even in non-invasive years.” By November, after the first strong cold front, shrikes were being reported statewide. Thirty were counted on CBCs in December and early January and shrike sightings continued until early March. Berks County in eastern Pennsylvania had the highest number (12).

Because there are few accounts of shrike ecology in North America, Hess summarized three notable features of our irruption, namely that 53% of shrikes (48) were adults and 47% (40) were immatures.

Secondly, only 20% held territories, and they were mostly adults, while the rest wandered, responding to food and weather conditions.

A house sparrow killed by a northern shrike at a bird feeder in North Dakota (Photo by Matt Reinbold on Flickr, Creative Commons license)

A house sparrow killed by a northern shrike at a bird feeder in North Dakota (Photo by Matt Reinbold on Flickr, Creative Commons license)

Thirdly, the prey they caught were primarily songbirds at bird feeders because meadow voles were scarce that year throughout the state.

Since that irruption, Pennsylvania has had two more, according to Greg Grove, who started the Winter Raptor Survey in 2000. Our second largest shrike irruption was 2007-08 with 80 shrikes in 39 counties. That was followed by a smaller irruption in 2011-12 with 44 shrikes in 27 counties.

Northern shrikes start returning north from Pennsylvania by the fourth week in February or first week in March. While they may pair up on winter territories, even far south, most courtship chasing, feeding, and aggressive displays by males toward females occurs on their breeding grounds.

Both sexes also sing either two-phrase, thrasher-like imitative songs of nearby bird species or sweet warbles and harsh screeches.

A juvenile northern shrike (Photo by Eric Ellingson on Flickr, Creative Commons license)

A juvenile northern shrike (Photo by Eric Ellingson on Flickr, Creative Commons license)

The male feeds the female during late courtship, nest-building, laying, incubation and the early nestling period. The female chooses the nesting site in late April or early May in shrubby willow trees or spruce conifers. She places it in a fork of a branch near the trunk usually eight feet from the ground. She also brings most of the nesting materials aided by the male. The nest is a large, deep, bulky cup filled with ptarmigan feathers, animal hair, and dried moss and lined with grasses and sedges.

In the nest she lays 4 to 9 grayish or greenish white eggs spotted heavily with brown and incubates them 14 to 21 days while the male is busy feeding her and defending a 360-acre hunting territory as well as a 7-acre nesting territory. Mostly the male hunts for grasshoppers, beetles, bumblebees, insect larvae and spiders during the summer months.

The offspring spend 18 to 20 days as nestlings and another several weeks as fledglings being fed by their parents and taught how to hunt. By mid-summer the fledglings are on their own, and sometimes the siblings stay together and join other broods of immatures as they continue to hone their hunting skills.

By mid-September these groups disperse and individually move along river corridors out of the boreal forest into open country. They also follow ridge lines like small hawks do, flying just above the tree tops as they head south for the winter.

Because seeing a northern shrike here in winter is a rare privilege, I don’t expect to see one hovering over our First Field this winter. But Pennsylvania is overdue for another northern shrike irruption

 

A Pandemic Year

December is my least favorite month. I used to call it the “freezing rain” month. But lately it has been giving me more varied weather from warm and sunny to cold rain, freezing rain, and snow.

Holding a maitake, also known as a hen-of-the-woods mushroom

Holding a maitake, also known as a hen-of-the-woods mushroom (Photo by Dave Bonta on Flickr)

Since I write my columns four months ahead of time, I’m writing this one during the extreme drought and heat of August and wondering what December 2020 will bring.

After being “locked down” here since early March, I was not looking forward to late fall and winter. We’ve been living on our central Pennsylvania mountain since August of 1971 and most winters have been a challenge during the best of times.

Now, with the pandemic raging, these are the worst of times that my husband, Bruce nd I never imagined during our younger years. But with Bruce at 79 with Parkinson’s disease, I must remain fit enough to take over more chores than ever, aided by our caretakers and our two sons—Dave and Mark—who are sometimes here and sometimes not.

Mark and Paola in the forsythia patch near the house

Mark and Paola in the forsythia patch near the house

Dave, unable to join his wife, Rachel, in London because of the pandemic, put in a large, fenced and mulched vegetable garden. He also did most of our food shopping, while Mark and his wife, Paola, did our banking, mail and drugstore pick-ups, and handled some of our larger property issues.

But by December, Mark and Paola may be off on new jobs, and Dave on a plane to the United Kingdom as soon as they open their country to Americans. Then it will be up to me to shop and handle all the other business our sons have been doing for us.

Steve and Zhouyue, “Joy,” at their wedding ceremony in China

Steve and Zhouyue, “Joy,” at their wedding ceremony in China

Our oldest son, Steve, is teaching English in an American-run school in Shanghai and he, his Chinese Christian wife, Joy, and daughter Elanor shared a one-room apartment during the pandemic there. He warned us via Skype to wear masks whenever we left the mountain, claiming it was the only way to avoid COVID-19 as he and his family had done.

Furthermore, Mark, Dave, and Paola lived in the guesthouse and only visited us outside on our veranda and six feet apart. Our other granddaughter, Eva, who lives and works in NYC, along with her boyfriend Geoff, also visited us outside and camped in a tent beside the barn. But once winter sets in, we will greet visitors on the veranda bundled up in our winter coats and hats. Already there have been days when such visits were a freezing challenge. However, if this winter is as warm as last winter, it should be fairly easy to survive and thrive.

Birds arrived in mid-February 2020 that usually arrived in mid-March and we were ready for an early spring. Instead, March blew in cold and we were faced with trying to avoid COVID-19. No more weekly food shopping, library visiting, and lunch in a restaurant in State College. But spring had arrived and I had plenty to do, trails to take here, and birds and animals to observe. We were congratulating ourselves that it was spring and easy for us to get out. We expected by summer that the pandemic would be over.

In the meantime, the spring continued cold but the Neotropical migrants returned according to schedule. Wildflowers bloomed a little later than usual, but by May 10 even the trees had leafed out. That morning we had an unprecedented freeze. It was 25 degrees at dawn, and the herbs I had planted on my back porch had blackened beneath their plastic cover.

Pink lady’s slippers

Pink lady’s slippers (Photo by Dave on Flickr)

In the woods, the tender new leaves on saplings had also blackened and eventually dropped. Ferns too, especially sensitive ferns, looked dead. The buds on most of our pink lady’s slippers drooped and instead of our usual 30 to 40 blooms, I found four late in the month. It had paid to be a late bloomer for that species. The mayapples also were affected, and their flower buds dried up. Never had we had such a hard freeze so late in the spring.

The year had started out rainy and our vernal ponds continued to be full. In early March they were crowded with hundreds of calling and mating wood frogs. Although the ponds began dwindling in June, they finally dried up in July. We had gone from extreme rain and storm events to a drought that challenged Dave and his garden. Often, in July, we could hear distant storms, but all we received was a misty day.

Dave and Rachel at their wedding ceremony on Sapsucker Ridge

Dave and Rachel at their wedding ceremony on Sapsucker Ridge

I left the mountain once in late July for fruit from the Amish in the valley and wore a mask. To my sorrow, the Amish orchard had lost all their apricots and most of their plums and early peaches because of the May freeze. Our wild blueberry crop had also failed. But I was able to fill our freezer with the black raspberries and blackberries I picked in our field and extra produce from Dave’s garden. Our caretakers gifted us with eggs from their free-range chickens. And I knew they would begin hunting as soon as archery season opened in early October.

Despite the setbacks in our food supply, living here surrounded by the natural world kept us sane and content. Bruce managed a walk down our road most days. He also did veranda-sitting and sunporch bird-watching. I rarely missed a day of walking up and down our trails. Dave preferred hiking in late afternoon in search of plants or during the night to observe fireflies, while Mark was up with the birds.

Spined micrathena

Spined micrathena (Photo by Dave on Flickr)

Both sons made discoveries they shared with me since they ranged farther and on steeper trails. We all bushwacked during the summer because there were no ticks anywhere from June through September. I even sat on the ground, my back against a tree, something I hadn’t done since the ticks arrived 15 years ago. The drought meant there were few biting insects too. But the spined micrathena spiders spun their usual orb webs across the trails in August.

Over in China, Steve too found bird-watching therapeutic and ranged far and wide in search of more species to add to his lifetime bird list that he first started here when he was seven years old. And he occasionally sent videos of his adventures with the tiny hedgehogs that lived on the school grounds.

In early November I will put up our bird feeders, which we’ve done for the almost 50 years we’ve lived here. I will also continue my participation in Project FeederWatch, which I began in 1989, even though the last several years have not been too exciting. Maybe this winter the northern finches will appear. Or maybe they won’t.

An eastern towhee

An eastern towhee (Photo by Mark in Plummer’s Hollow)

Last December it was so mild one day that a chipping sparrow appeared with the juncos at the feeders. And an eastern towhee wintered off Bird Count Trail, a discovery I made in December. We averaged 12 to 15 species at our feeders most days and more gray squirrels than we liked. But because of the excessive rain and then the freeze this year, acorns have been scarce for three years, although the scrub oaks did produce this year. American tree sparrows were sparse but we usually had a couple at the feeders. Still, they were so few that we didn’t hear their melodic calls during the winter.

The mild winter was a boon to the Carolina wrens that sang through even the few cold days that we had. The local Canada geese flock flew over every morning at 10:30. At least one field sparrow joined the First Field flock of song sparrows and white-throated sparrows.

Mark’s photo of a hermit thrush in Plummer’s Hollow

Mark’s photo of a hermit thrush in Plummer’s Hollow

Coming home one evening with Eva late in December we saw an opossum at the gate, and on another night she and Geoff had a good view of a fisher running up our hollow road ahead of their car. I did my usual tracking in the frequent light snows and Mark his bird-watching. He not only found my eastern towhee but a hermit thrush as well above Bird Count Trail.

At the end of the month, I went for a walk in the silent forest at 2:30 in the afternoon. The light was the slanted light of winter but it was 65 degrees. I wondered if it was late fall, early spring, or an incredibly late Indian summer day. In any case, we enjoyed the halcyon winter days of 2020, unaware of the pandemic to come.

Now, in December of 2020, however long it takes before we can emerge from our self-imposed isolation, this pandemic year will be one to remember, a year when the natural world became even more of a solace than it has been for our family throughout our lifetimes.

 

Female Songsters

Last November dozens of migrating white-throated sparrows took refuge in our fields and forests during the early cold and snow. Despite the weather, they sang their “poor Sam Peabody, Peabody, Peabody” song and occasionally they were joined by a singing song sparrow. Like most birdwatchers, I assumed the singers were male, but I may have been wrong.

A white-throated sparrow in Alabama

A white-throated sparrow in Alabama (Photo by Patricia Pierce on Flickr, Creative Commons license)

Researchers have found that northern female songbird chicks still have a brain area for singing that has atrophied in those species where females no longer sing. Furthermore, Karan J. Odom, at Leiden University in The Netherlands and Lauryn Benedict at the Cornell Lab of Ornithology published a paper in The Auk in 2018 asking scientists and birders to spread the word that the females of most tropical and some temperate songbirds do sing. Previous work by Benedict and others found that 42% of female songbird species found in the United States and Canada and 43% of European songbirds have some song.

Odom and Benedict appended to their paper a list of the singing North American female songbirds based on information from The Birds of North America (BNA) life histories of all North American bird species. (The BNA has recently been incorporated into Birds of the World.) Currently, there are 144 species, 67 of which breed, live year-round, or migrate through Pennsylvania.

The list favors those species where females are drab-colored and males flashy, such as common yellowthroats and red-winged blackbirds, which enable observers to easily tell them apart, but there are some, such as black-capped chickadees and tufted titmice, where the sexes look alike.

A female northern cardinal in the Codorus State Park, Hanover, PA

A female northern cardinal in the Codorus State Park, Hanover, PA (Photo by Henry T. McLin on Flickr, Creative Commons license)

Sometimes females have their own unique song while others closely resemble the males’ song. For instance, northern cardinal females sing the same “cheer, cheer, cheer” song as the males, but female red-winged blackbirds sing a rapid “btut-tut-tut” in answer to the males’ “okalees.”

Of the birds I saw at my feeders and in the forest and fields last November, 10 species have singing females—American crows, black-capped chickadees, tufted titmice, house finches, eastern towhees, fox sparrows, song sparrows, northern cardinals, dark-eyed juncos, and white-throated sparrows.

Female chickadees sing a faint “fee-a-bee,” which is lower in volume than the males’ “fee-a-bee” during breeding, but females sometimes sing “fee-a-bee” loudly throughout the rest of the year as well as the “chick-a-dee” call, according to Susan Smith, who studied black-capped chickadees for decades and wrote the BNA account.

Many female bird species sing but this female eastern towhee also has attitude

Many female bird species sing but this female eastern towhee also has attitude (Photo by Kelly Colgan Azar on Flickr, Creative Commons license)

Male and female eastern towhees call “che-wink,” and once, back in 1958, a mated female towhee in Indiana sang an “unmusical, flat, somewhat squeaky” song, V. Nolan, Jr. reported. Jon S. Greenlaw in 1971 in New York state heard a female sing “two weak, husky, flat ‘shreeeeee’ trills from high perches and then flew, followed by her mate, who was nearby, according to his BNA paper.

White-throated sparrow females sing the same song as males, but their songs are shorter and their notes less steady in pitch. Occasionally, they sing even in fall migration and during the winter, J.B. Falls and J.G. Kopachena report in the BNA.

Other BNA research pieces report that tufted titmice females sing “peter-peter” like the males do, but the females’ song is lower in pitch. Fox sparrow females also sing the same song as the males, but their song is softer and shorter than the males’ song. House finch females too sing a simplified version of the males’ song, as do female song sparrows.

Margaret Morse Nice studying a nest of baby field sparrows

Margaret Morse Nice studying a nest of baby field sparrows (Photo by Al Fenn on Wikipedia, fair use license)

Margaret Morse Nice, who studied song sparrows intensively for decades in Ohio, found that female song sparrows sing rarely, especially in response to territorial conflicts with female intruders in the spring, and she reported in 1943 that only 11 out of 200 females she observed sang. Canadian researchers in 1988 seemed to agree with Nice’s research because they found that a mere 12 of 140 females they studied in British Columbia sang.

Odom and Benedict in their paper reported that they and their colleagues have started the Female Bird Song Project at Leiden University and the Cornell Lab of Ornithology. They asked that birders, researchers, and wildlife recordists around the world listen for female bird song and deposit their observations and recordings of female songs in biological collections. They further suggested that birders could easily upload their audio recordings of singing females to the Cornell Lab’s Macaulay Library with their eBird checklists. They also gave pointers on how to write descriptions of the songs and how and where they were heard as well as the kind of video recordings participants in the Female Bird Song Project should do. Their goal is to find as many female songbird singers as possible.

They suspect that migratory behavior among many northern bird song species may make it safer for the singing males to defend territories while the females quietly go about nest-building and tending young in the few months they have on their nesting grounds.

A female dark-eyed junco

A female dark-eyed junco (Photo by Tom Murray on Flickr, Creative Commons license)

This seemed to be proved recently on the campus of the University of California in San Diego when dark-eyed juncos there stopped migrating and then the females started singing. According to Dustin Reichard, who is studying this phenomenon, the female juncos sing to stop other females from copulating with their mates.

Another recent singing female was observed in June 2017 by Alexander Sharp, a graduate student at Ball State University. In Yellow Wood State Forest in southern Indiana where Sharp was monitoring a cerulean warbler nest in a tree 50 feet above the ground, the male was singing. He also heard a higher-pitched but repetitive “zeet” like a male bird’s song coming from the nest. He thought, since it was mid-June, that it was a nestling learning the male’s song.

But the next day, when he returned to the nest with other university researchers, they heard the same different call. However, when the “singer” peered over the nest edge, they were shocked to see that it was a female.

A female cerulean warbler

A female cerulean warbler (Photo by Alan Schmierer on Flickr, Creative Commons license)

Then, less than a week later, they found a second female singing a “truer song that was long, rhythmic, and complex.” She sang only while foraging with her mate, while the first singer seemed to be singing an encore to her mate’s song.

Even though Ball State University scientists had been studying cerulean warblers for 20 years, this was the first time they had recorded female bird song in this species. They not only wrote about their discovery in The Wilson Journal of Ornithology in June 2019, they made excellent video recordings of the female singers and put them up on YouTube where I enjoyed watching and listening to the female songsters.

Ornithologists are also looking more closely at female songbird behavior. Ornithologist Bridget Stutchbury, working in northwestern Pennsylvania, discovered that hooded warbler females were leaving their nesting territories every three hours to search for extra-pair copulations, she told writer Kathi Borgmann in her excellent article in Living Bird “The Forgotten Female Now a Focus of Study,” upending her belief and those of other ornithologists that only males look for extra-pair copulations. Stutchbury also found that female blue-headed vireos left their nesting territory after their eggs hatched to look for males. Then, when their young fledged, they left with another male and their first mates cared for the fledglings alone.

Ruth Bennett, formerly a doctoral student at Cornell and now a postdoctoral researcher at the Smithsonian Migratory Bird Center, studies Neotropical migratory songbirds on their wintering grounds. She has discovered that in two-thirds of the species she studies, the males and females use different habitats. This means that when conserving land for such species, most notably the rapidly declining golden-winged warblers that Bennett specialized in, both habitats must be preserved.

Kenn Kaufman, an extraordinary birder and the author of several books about birds as well as bird guides, recently wrote an article entitled “I Became a Better Birder When I Stopped Focusing on the Males” for Audubon online back in 2018. “Females pass judgment on whether a male’s display attracts them,” he wrote. “They also defend territories, usually build the nest, often travel farther than males and move to more distant wintering areas.” He adds that a female, “represents her species as well as the male could, and probably has more interesting behavior.”

As scientists continue their research on female bird song and behavior, all of us who are fascinated by birds will look forward to their findings. And I, like Kaufman, will spend more time observing our female songbirds.

SGL#166 Beaverdam Wetland

On a rainy Sunday afternoon in early October, my husband Bruce and I joined fellow members of our Juniata Valley Audubon Society on a field trip to SGL#166.

George Mahon, a member of the Juniata Valley Audubon Society, in the Beaverdam area

George Mahon, a member of the Juniata Valley Audubon Society, in the Beaverdam area (Photo by Bruce Bonta)

This 11,776-acre game land includes the Beaverdam Wetland Biological Diversity Area (BDA), which is tucked in a remote wooded valley in southern Blair County between Canoe and Brush mountains and forms the headwaters of Canoe Creek. And it lives up to its name because beavers still occupy the creek and wetlands.

Since Beaverdam Road is only open during big game seasons to a parking lot four miles from the game land’s southern boundary, we had a reasonably short hike on the gravel road to reach the Beaverdam area.

The rain stopped when we started off through a diverse upland hardwood forest that includes such trees as American basswood, sugar maple, and white oak, as well as limestone-loving yellow or chinquapin oak and the thicket-forming shrub or small tree American bladdernut that favors moist, floodplain forests and stream banks.

A winterberry growing along the trail

A winterberry growing along the road (Photo by Bruce Bonta)

From the road I saw invasive stiltgrass and garlic mustard and occasionally a fern understory, but according to the Beaverdam Wetland BDA report, this forest also contains the usual invasive multiflora rose, Japanese barberry, and European privet as well as the native spicebush and black haw shrubs. We also stopped to admire a young American chestnut tree, a patch of partridgeberry and a winterberry, covered with red berries.

The BDA report lists a wide variety of spring wildflowers in the forest such as blue cohosh, wild ginger, jack-in-the-pulpit, mayapples, false Solomon’s seal, yellow fairy bells, and sweet cicely.

We were in, what I later learned from Justin Vreeland, Regional Wildlife Management Supervisor for the Southcentral Region of the Pennsylvania Game Commission, is the Canoe Creek Old Forest Unit (OFU), a 3,922-acre portion of the game land managed for late-successional forest attributes.

A view of Canoe Creek in the Canoe Creek State Park, downstream from the Old Forest Unit

A view of Canoe Creek in the Canoe Creek State Park, downstream from the Old Forest Unit (Photo by David Brossard in Wikimedia, Creative Commons license)

In addition to protecting the Canoe Creek riparian zone, it is hoped that this contiguous tract of mature hardwood forest will attract many forest-interior and riparian birds of conservation interest including Acadian flycatchers, blackburnian, black-throated green, black-throated blue, worm-eating, Kentucky and cerulean warblers, Louisiana waterthrushes, red-shouldered and broad-winged hawks, scarlet tanagers, wood thrushes, and yellow-throated vireos.

During our visit our bird list was meager—gray catbird, blue jay, eastern towhee, field sparrow and ruby-crowned kinglet—due to the weather and because most of the previously mentioned forest birds were already on their way south for the winter.

The beaver pond in the wetland area

The beaver pond in the wetland area (Photo by Bruce Bonta)

Once we reached the wetland complex with beaver ponds on either side of the road, the trees and shrubs changed to what the BDA report describes as “a mosaic of graminoid [grassy] meadow, shrubland and palustrine [wetland] forest communities.” The BDA report adds that “the floodplain holds an especially interesting palustrine woodland with a high diversity of plant species,” such as poison sumac, royal, interrupted and marsh ferns, white turtlehead, yellow marsh marigold, five sedge and two grass species.

We saw the shrub buttonbush and the vine virgin’s-bower, both wetland species, as well as thickets of alder. The bark of the latter is sometimes eaten by beavers, although they prefer aspens above all, followed to a lesser degree by willows, but they will eat the bark of other tree species if neither aspen nor willow are available. In spring and summer months, they switch to non-woody vegetation especially grasses and aquatic plants.

For instance, a study in Mississippi found in the stomachs of beavers material from 42 tree species, 36 genera of green plants, four kinds of woody vines and a lump of grasses, according to Ben Goldfarb in his engaging book Eager, the Surprising Secret Life of Beaver and Why They Matter. He writes that “beavers are among our closest ecological and technological kin” because both humans and beavers are “wildly creative tool users who settle near water, share a fondness for elaborate infrastructure, and favor fertile valley bottoms carved by low-gradient rivers.”

Before Europeans arrived in North America, researchers calculated that the continent had between 15 and 250 million beaver ponds. “The Lehigh River,” Goldfarb writes, was “almost choked with beaver dams, which helped form the ‘Great Swamp’ at its headwaters…” Beavers still change the landscape and by doing that create prime songbird habitat.

A beaver dam

A beaver dam (Photo by Tom Gill on Flickr, Creative Commons license)

In another study in coastal Maryland back in 2000, researchers found that a single beaver pond slashed the discharge of total nitrogen by 18%, phosphorus by 21%, and total suspended solids—waterborne particles classified as a pollutant by the Clean Water Act—by 27%.

These clever engineers build their dams for safety from predators—black bears and coyotes in our area—shelter from weather, and food storage. Propelled in water by their webbed feet, they can hold their breath for 15 minutes, have transparent eyelids that allow them to see underwater, and a second set of fur-lined lips behind their upper and lower chisel-shaped teeth, that enable them to chew and drag wood without drowning.

Beaver fur consists of two-inch-long coarse guard hairs over a soft, thick, buoyant and waterproof underfur. A Scrabble-letter-sized patch of it has as much as 126,000 individual hairs, more than we have on our heads. Their flat, scaly tails are rudders and alarm systems and they have a net of tightly meshed blood vessels that can regulate their temperature.

A beaver at work

A beaver at work (Photo by Tim Lumley on Flickr, Creative Commons license)

They fell trees by balancing on their back legs with their tails beneath their bodies, and use their large teeth to chip away at the trunk until the tree falls. Then they gnaw off the branches and cut the trunk into manageable pieces before hauling them off to their building site. Researchers report that 62% of the trees beavers cut fall in the direction of the dam they are building. They peel their lodge or dam sticks and eat the inner bark before weaving them into their constructions.

The dams they build can be as small as a couple feet to half-mile-long dikes. A family unit of between four and ten consisting of mating adults, newborn kits, and yearlings can build and keep up more than 12 dams and change a narrow stream into a broad chain of ponds. They also construct burrows and lodges where they sleep, raise kits and winter. Since they don’t hibernate the adults spend the winter dragging sticks and roots from their submerged larder to feed their family.

Needless to say, we didn’t see any beavers during our field trip. Vreeland hopes to develop higher-quality beaver habitat along Canoe Creek by planting aspens.

The Canoe Furnace used trees from the Canoe Valley as fuel

The Canoe Furnace used trees from the Canoe Valley as fuel (Photo in the Penn State Special Collections in Flickr, Creative Commons license)

There have always been beavers in this valley, although trees were first cut as early as 1807-1809 and into the 1870s to fuel Canoe and Etna iron furnaces. A lumber railroad operated in the upper Canoe Creek watershed and mining railroads along the southern ridge.

Since that time, at least one lumber company early in the twentieth century “turned [the valley] from a splendid forest to a desert waste,” according to outdoor writer and hunter, Harry P. Hays, who frequented the valley then. He also visited Margaret Aurandt, whose grandfather, John Hancuff, was the first settler in the valley in the early nineteenth century.

Aurandt was born in 1866 and lived in the valley most of her life, the last 17 years—from 1912 to 1929— alone and on her own, “her friends the trees, birds, flowers, animals, and other things of the forest. Her home stood at the edge of a magnificent stand of white pine trees, where the mid-day sun could only send scattered shafts of gold.” The logging “was a great blow to the lonely woman, who grieved deeply, and was bereft of much of the former joy of her woodland life,” Hays writes.

One hundred years have passed since the logging occurred. I think Aurandt would be pleased to learn of the establishment of the Canoe Creek Old Forest Unit, which Vreeland hopes will benefit many mature-forest-dependent species including a wide variety of birds such as northern goshawks, wild turkeys, and winter wrens, as well as mammals—fishers, silver-haired bats, white-tailed deer, black bears, gray and southern flying squirrels.

Furthermore, according to the comprehensive management plan for the OFU (shared by Mr. Vreeland), officials want to “promote late-successional forest conditions on higher quality soils.” Such forests “are rare because these historically were converted to agricultural land uses or subject to multiple timber harvests.” For this reason, large parts of the OFU are on good growing sites for both hardwood and conifer forests. The plan also calls for providing “an extensive area of unfragmented forest,” although it is now bisected by the game land’s road and a 100-meter-wide electric right-of-way corridor.

Still, the OFU is unique in southcentral Pennsylvania, and Vreeland says in an email, “I firmly believe if we are to conserve wildlife diversity, we need to maintain forests, to include areas largely left to nature’s processes, on an array of soil types, including productive ones, because these will produce different structural and compositional characteristics than a similarly aged forest on poorer soils.”