Squirrel Wars

Last autumn, our granddaughter Eva, who was staying with us for several months, started complaining about the noise in the attic above her bedroom.

The squirrel cage in our attic (Photo by Bruce Bonta)

The squirrel cage in our attic (Photo by Bruce Bonta)

At first, I dismissed it as the usual small animal noises on the roof or even in the attic. My bedroom was next to hers and I wasn’t hearing anything out of the ordinary. After all, Eva had lived in town homes all her 22 years and wasn’t used to country life in an old (1871) clapboard farmhouse.

Back in 1971, after we bought our home, we told the contractor who was putting in a second floor bathroom that we were hearing animals in the walls rolling black walnuts.

The contractor, who had worked for the previous owners for decades said, “Oh, that’s the red squirrels. This place has always had them in the walls and attic. That’s why I built the squirrel cage in the attic.”

The squirrel cage is a six foot by 12 foot construction of stiff, fine wire mesh, hardware cloth in which we were instructed to store all items that squirrels might chew on or use as nesting material.

An American red squirrel eating a nut

An American red squirrel eating a nut (Photo by Connormah in Wikipedia, Creative Commons license)

For two years the squirrels continued their lives in our home until my husband Bruce’s parents moved into our guesthouse. I mentioned the squirrels to Pop, and one day, when I came home from shopping, Pop pointed proudly to my clothesline. Hanging by their tails were two dead red squirrels that he had shot. That deed ended the rollicking in our walls and attic, and, in fact, the red squirrel population on our mountain.

Now, more than four decades later, Eva’s complaints continued. Finally, in mid-December, I too began to hear running feet above my ceiling. I wondered if the red squirrel population had recovered but had seen no sign of any in the woods. Then, on a dreary December 29 morning I heard a commotion in the attic. I opened the attic door in my study and saw not a red but an eastern gray squirrel peering down at me. It had used the juniper tree outside my study window as a springboard to the eaves where it had chewed a hole into the attic.

Our caretaker, Troy, repaired the eaves, but he worried that the squirrel might be trapped in the attic, so he set a live animal trap where I had seen the squirrel and baited it with shelled peanuts. The following morning I heard scrabbling in my bedroom ceiling. Troy had caught a squirrel in the trap. Later he released it several miles from our home and re-set the trap.

A gray squirrel at a bird feeder

A gray squirrel at a bird feeder (Photo by Orest Ukrainsky in Flickr, Creative Commons license)

In the meantime, I battled gray squirrels at our three bird feeders hanging from our back porch and on the ground below where they gobbled up most of the birdseed I spread for the birds. Never in all the years we lived here had we had so many squirrels at our feeders. Our dozens of black walnut trees had had few black walnuts, and the acorn crop in our forest had been sparse for the second year in a row.

Meanwhile the squirrel wars continued in the attic. The peanuts were eaten night after night in the trap but no creature was caught. On the morning of January 13 I watched a squirrel climb the juniper tree, stopping occasionally to eat some snow. I alerted Bruce and he saw the squirrel leap on to the roof and come into the attic by way of a new hole it had chewed near the old, patched one.

Troy climbed the ladder to patch the new hole and carefully examined the eaves around the house for new holes but found none. Later, he returned with a trail camera tied to a heavy paint can that he put near the live animal trap. He baited the trap with a plastic cylinder peppered with small holes and filled with shelled peanuts.

At 2:00 a.m. I heard a squirrel run across my bedroom ceiling. The trap was not sprung and the cylinder was gone. I began to think we had Einstein squirrels in residence.

Game cam image of a gray squirrel in an animal trap in our attic

Game cam image of a gray squirrel in an animal trap in our attic (Photo courtesy of Troy and Paula Scott)

That evening Troy came by to check his camera. It looked as if three gray squirrels, one flying squirrel, and a short-tailed shrew had figured out how to get into the trap, grab the capsule and/or previously the peanuts, and escape without springing the trap.

I wasn’t too concerned about the flying squirrel. Apparently, southern flying squirrels sometimes live in attics, “gain[ing] access through windows, crevices under eaves, and similar apertures to the attics of homes,” according to one researcher as quoted in Flying Squirrels: Gliders in the Dark by Nancy Wells-Gosling, p.112. Probably they are the creatures that I do sometimes hear in the attic or walls, but their sounds can’t be compared to the noise of gray squirrels.

A short-tailed shrew

A short-tailed shrew (Photo by Gilles Gonthier in Flickr, Creative Commons license)

The short-tailed shrew, on the other hand, was a puzzle. They do eat plant food, including corn and beechnuts during the winter, and, judging by our attic shrew, shelled peanuts as well. Still these are burrowing animals not known to live in houses, although I once found one in a bucket in our basement.

The weather worsened with cold and snow, and we declared the attic war a stalemate. Troy’s last check of his trail cams showed only one flying squirrel left in the attic. Besides, it was dangerous for Troy to use the ladder, and we hoped his latest eave repair would deter any more destruction by the gray squirrels.

But the squirrel war outside continued. After an eight-inch snowstorm on January 19, followed by minus one degree Fahrenheit the next day, the birds and squirrels were desperate for food especially since ice-covered snow was as deep as a foot in the forest.

From two above zero on January 21, the temperature rose above freezing, and it rained for two days, and then the thermometer dropped to 22 degrees. Our feeders and the ground below was swamped by 15 bird species and at least seven hungry gray squirrels. They were joined in the dawn light by a large cottontail rabbit.

Feeder birds blanketing the snow

Feeder birds blanketing the snow (Photo by John in Flickr, Creative Commons license)

To give more ground-feeding birds a chance against the squirrels, I started throwing birdseed out on the frozen snow on the opposite side of the house near the veranda. This worked for a couple days until the squirrels caught on and managed to dominate both feeding areas. However, on the last day of January it was seven degrees below zero. Birds, especially the white-throated, song, and American tree sparrows and dark-eyed juncos, blanketed the ground below the back porch and on the veranda side, but the squirrels gave up earlier than usual.

The continual snow, rain, and freezing that characterized most of February brought more gray squirrels to the feeding areas. But most returned to their tree nests in the forest every evening. The two most aggressive ones stayed close to the food. One lived beneath our generator near the back porch and the other stayed in the juniper tree even when it was snowing hard. I assumed they were two of the original attic dwellers.

By February 23 we had 11 gray squirrels, and they began attacking our two tube feeders. One squirrel pulled out the plastic guards around the holes of a new red metal feeder I had received at Christmas and ate all the seeds. Never had I had to fight such determined and bold squirrels. Another climbed up our back porch storm door, trying to get inside late one morning while our son Dave was eating in the kitchen.

A relatively squirrel-proof bird feeder hangs on our back porch (Photo by Bruce Bonta)

A relatively squirrel-proof bird feeder hangs on our back porch (Photo by Bruce Bonta)

Finally, the squirrels defeated me, especially the three biggest, boldest pests that never quit for the day, and I removed the tube feeders, leaving only a much larger, relatively squirrel-proof feeder to feed the birds. Still, they mobbed the porch, and when I threw out pounds of mixed seeds for the birds, the squirrels ate most of it.

Our outdoor squirrel war continued even into mid-March, and I acknowledged utter defeat by the 11 squirrels that never left until the snow melted.

On the other hand, we never heard or saw another gray squirrel in the attic so you could say that our squirrel war of 2018-2019 was a draw.

 

The Art and Science of Feeding Birds

I first began feeding winter birds in November 1968 when we lived in rural central Maine for five years. At the beginning of November, I hung a feeder filled with sunflower and mixed seeds from the yard American elm tree, but it wasn’t until a wet, snowy November 10 that the first birds appeared. I glanced out a window of our cape-style farmhouse to see 11 evening grosbeaks in the feeder and on the ground beneath. After that, the grosbeaks appeared during snowstorms throughout late fall, winter and early spring.

Evening grosbeaks on a bird feeder

Evening grosbeaks on a bird feeder (Photo by Linda on the bridge to NewWhere on Flickr, Creative Commons license)

The following winter the grosbeak flock numbered as many as 100 on snowy days. They were joined by common redpolls, American tree sparrows, blue jays, white-breasted and red-breasted nuthatches, black-capped chickadees, hairy and downy woodpeckers, and a few slate-colored juncos. Even then, I was listing numbers and species and watching and recording their antics in and around the feeders.

When we moved to Pennsylvania in late summer of 1971, I hung our feeder from the top of our back porch, five feet from the kitchen door, and spread seed on the back steps and cement pad beneath. Back in Maine our active bird feeder had provided entertainment for the whole family especially our three young sons. And I was eager to see what species would visit our new home.

Evening grosbeaks made occasional visits, but there were only a few of them at any time, and before the end of the century there were none. Then, as now, white-breasted nuthatches are the first birds to spot me putting up the feeder every November. Common redpolls are uncommon visitors once or twice every other year. Blue jays, too, are intermittent visitors, having cached acorns for the winter, unlike in Maine where oak trees were scarce and we hosted 14 blue jays at a time. American tree sparrows are almost as numerous here as they were in Maine even though Maine is closer to their boreal breeding grounds. Slate-colored juncos, lumped together with several other junco species in 1983 and re-named dark-eyed juncos, are more numerous in Pennsylvania.

Hand feeding a black-capped chickadee

Hand feeding a black-capped chickadee (Photo by Yvon Hache on Flickr, Creative Commons license)

Hairy and downy woodpeckers rarely visit our feeders here because they have a large forest of deciduous trees they forage on. But in Maine we lived in the country surrounded by fallow fields that attracted bobolinks and eastern meadowlarks in the spring. Beyond the fields was a patch of mature white pines along a lake that hosted dozens of small vacation cabins, so there were less trees to furnish insects for woodpeckers.

We had black-capped chickadees in both places, and I learned to handfeed them here where it isn’t too cold to stand outside next to an empty feeder, my palm outstretched and filled with sunflower seeds. Usually, they landed on my hand within 20 minutes. It took the tufted titmice, watching the chickadees, a little longer to venture near.

Tufted titmice and northern cardinals weren’t residents in central Maine in the 1960s as they are now, so I was pleasantly surprised when they appeared at our Pennsylvania feeder. And not so pleasantly surprised when gray squirrels raided it. In Maine, gray squirrels rarely appeared and the more common red squirrels stayed in the pine forest. After struggling to keep the squirrels from our open, wooden feeder in Pennsylvania, I replaced it with a couple tube feeders, which they have not had much success invading.

A red-bellied woodpecker at a feeder in Pennsylvania

A red-bellied woodpecker at a feeder in Pennsylvania (Photo by Rona Proudfoot on Flickr, Creative Commons license)

In Pennsylvania the first red-bellied woodpeckers, previously a southern species, arrived in our yard in 1980, and after a few years became the most common of our feeder woodpecker species. In 1986 Carolina wrens, another southern species, visited the feeder area, although several times their numbers were reduced after severe winters. Lately, though, our warmer winters have kept them alive and thriving.

Once Project FeederWatch was launched in 1987 by the Cornell Lab of Ornithology, I started paying even more attention to feeder birds, devoting portions of two consecutive days each week to counting numbers and species.

Writing in Living Bird, the magazine of the Cornell Lab, Gustave Axelson summed up some of the results of Project FeederWatch studies. Common red polls used to irrupt south from their boreal breeding grounds every other year when aspen and birch seed crops were lower, but beginning in 2005, some FeederWatch counts in low redpoll years have been higher than expected and may mean that food in the boreal forest is scarcer.

A cooper’s hawk with its catch near a bird feeder

A cooper’s hawk with its catch near a bird feeder (Photo by Tony Alter on Flickr, Creative Commons license)

Cooper’s hawks are not migrating to Mexico as much as they used to. Many hang out near feeders, as many bird feeder watchers can attest to, probably because they have learned that feeders attract large numbers of prey such as dark-eyed juncos and American goldfinches, but their predation has not affected the overall numbers of these common species.

Northern cardinals have expanded their range and are now reliable feeder birds as far north as Quebec, New Brunswick and Nova Scotia not only because of bird feeders but because more people are landscaping their yards with shrubbery that provides cardinals with more food and cover.

Biologist Bernd Heinrich, writing in Natural History, recounted his studies on how birds managed to recognize and then use a food as foreign to them as cultivated sunflower seeds. First he watched as white-breasted nuthatches and black-capped chickadees often picked up seeds and then threw them aside. Heinrich opened those seeds and found them empty of a nut. He hypothesized that the birds were testing the weight of every seed, knowing that if it was too light, it was useless as food.

A black-capped chickadee opening a seed

A black-capped chickadee opening a seed (Photo by Christa R. on Flickr, Creative Commons license)

Heinrich also began to observe how each species ate oil sunflower seeds because their bills weren’t designed to handle this unnatural food. It took a chickadee 35 seconds to grab a seed, fly always to the same nearby maple tree, perch on a slender branch on which it could curl its toes around and over the seed, hammer it open with its bill, extract and eat the seed and fly back to the feeder for its next seed, actions that I and other bird feeder watchers have observed. But Heinrich thought to time it and to further add that, “broadly speaking, the branch constitutes tool-use.”

Blue jays do the same as chickadees, although they need a larger branch for their larger feet. They too use the same branch over and over, but unlike chickadees that don’t cache their seeds, a blue jay will sometimes fill its buccal pouch with seeds and fly off to cache them.

Nuthatches and woodpeckers take the seeds, one at a time, fly with it to a favorite cleft in tree bark, shove it in the cleft, break it open with their beak, and eat the nut.

Wild turkeys at a feeder in Pennsylvania

Wild turkeys at a feeder in Pennsylvania (Photo by Aaron of NEPA on Flickr, Creative Commons license)

Heinrich also wondered about predation risk and hypothesized that, “if feeding efficiency is measured in terms of the least time needed to forage for the most food secured,” then mourning doves and wild turkeys are best at this. Heinrich’s doves come at first light and dusk for three minutes at a time and eat 90 seeds a minutes. They spend the rest of the day sheltered in a spruce/fir thicket digesting the seeds. Wild turkeys eat 135 seeds a minute. Both species have crops where they store their seeds. While resting, they move the seeds to their gizzards where they are ground up.

A Cornell Lab study tackled the question of how black-capped chickadees, tufted titmice, white-breasted nuthatches and house finches weighed the possibility of starving on a cold winter’s night to risking predation while eating birdseed to sustain themselves. They set up feeders near the Lab’s headquarters that contained radio frequency identification (RFID) technology. Then they captured and fitted the birds with little RFID tags which enabled those feeders to record every bird’s visit. In two winters they recorded 472,368 feeder visits by 94 tagged birds.

All four species began eating at the feeders a half hour before sunrise and visited more and more frequently as the day passed Their numbers peaked two hours before sunset and then declined sharply for all but the white-breasted nuthatches. They hypothesized that the birds are less concerned about day-flying predators—Cooper’s and sharp-shinned hawks—than they are nocturnal predators, primarily eastern screech-owls.

A tufted titmouse at one of our feeders

A tufted titmouse at one of our feeders (Photo by Eva Bonta and used with her permission)

Still another Lab study was on whether bird-feeding hurts or helps birds since more than 50 million North Americans feed one million tons of seed to birds every year. They studied 98 species of birds that use feeders the most and found that they do as well or better than those birds that don’t use feeders. Feeder species showing declines, such as evening grosbeaks, seemed to because of other pressures like habitat loss.

Conversely, those that needed the most help, such as seabirds, shorebirds, and tropical birds, are not feeder birds so we aren’t helping the neediest birds.

Still, no matter where we hang our feeders, we can feel a connection to the natural world that may inspire us to advocate for those many species that need our help.