Breeding Owls in Maine

By in Foraging, Reproduction, Species Accounts

Although April has barely arrived, nesting season has begun.  Birds of prey take a long time to fledge young so their breeding season starts early.  For example, Great Horned Owls incubate their eggs for five weeks and the young do not take their first flight for another seven or eight weeks.  Owls are courting now, accomplished mostly by vocalizations.  Now is a great time of go owling.

Let’s consider the three most common owls in the state.  We’ll cover their distinctive calls as well as their morphology, diet and habitat preferences.

Barred Owls are common residents of woodlands, particularly around lakeshores and swamps.  These birds are gray with distinctive vertical black and white lines on the underside. Barred Owls have large, brown eyes; all the other owls in the state have yellow eyes.

Barred Owls are active at night and at twilight.  They are heard far more often than they are seen.  The booming call of the Barred Owl has been described as “Who cooks for you? Who cooks for you-all?”.  Once you have heard the call, it becomes instantly recognizable.

Barred Owls have a fairly broad diet.  Small mammals like mice, voles and squirrels compose much of their diet although birds up to the size of Belted Kingfishers, turtles and even insects may be taken.

Great Horned Owls are perhaps nearly as common as Barred Owls in Maine.  Unlike a Barred Owl, a Great Horned Owl has two tufts of feathers on the top of its head that form the “horns”.  With a wingspread up to five feet, these owls are impressive birds.  The plumage is generally brown with some white feathers on the throat and cross-barred markings on the breast.

Capable of flying on silent wings and equipped with massive talons, Great Horned Owls are efficient predators.  Like the Barred Owl, Great Horned Owls hunt mainly at night and at dawn and dusk.  These birds can kill birds as large as pheasants, Red-tailed Hawks and Barred Owls and mammals as large as mink and domestic cats.

The call of the Great Horned Owl is a five- or six-note call, consisting of resounding hoots in the following cadence: hoot hoot-hoot hoot hoot.

The last of our common owls is the small Northern Saw-whet Owl.  Only eight inches long, Saw-whet Owls are endearing little predators.  They feed primarily on mice as well as young squirrels, chipmunks and small songbirds.

The common name of this owl presumably comes from one of its calls that can be likened to the sound that is made when a mill saw is sharpened or whetted.  The typical call is a series of monotonous whistles that seem to go on forever.

Saw-whet Owls are birds of dense forests, especially coniferous forests.  These owls are strictly nocturnal.

An owl prowl may well yield all three of these owls by aural identification. All of these owls will respond to imitations of their calls.  You might enjoy driving some back roads after dark, stopping periodically to listen for the sounds of owl courtship.

The Eastern Screech-Owl is a common bird throughout the eastern United States to our south but is quite rare in Maine. The Maine Bird Records Committee currently recognizes only four records for the state, all from the central part of the state.

Eastern Screech-Owls give two distinctive calls.  One is a long, tremulous trill and the second is a whinny, a string of descending notes.  Evan Glynn, Josh Fecteau, Andy Aldrich and Kevin Couture heard an Eastern Screech-Owl in York, Maine on March 22. They were able to get a recording to confirm the record. A very nice discovery!

To prepare yourself in advance of an owl prowl, I recommend visiting the Cornell Laboratory of Ornithology’s website, http://allaboutbirds.org  You can search for any species of North American bird.  The information will include several sound recordings.

Bohemian Waxwings

By in Foraging, Identification, Species Accounts

Regularly irregular or irregularly regular? I can’t decide.  I’m musing on the most enigmatic of our winter visitors, Bohemian Waxwings.

This species is one of a hodgepodge of species that stage irruptions into Maine from more northerly areas, presumably driven by food shortages. This group of birds also includes Red-breasted Nuthatches, Northern Shrikes, Snowy Owls, Great Gray Owls and a number of northern finches.

Bohemian Waxwings were nearly as scarce as hens’ teeth on Maine Christmas Bird Counts this year. I did not lose hope as I know that we usually get some of these gorgeous birds in Maine by the end of the winter.

On February 4, John Wyatt reported a flock of 2,000 Bohemian Waxwings over his house in Winterport.   He photographed the flock so we know his count is accurate.

Learning of John’s report, I stepped up my vigilance for spotting some waxwings.  With the abundance of ornamental fruit trees on campus, Colby College is a magnet for the fruit-eating Bohemian Waxwings.  Walking across campus on February 18, I heard the buzzy calls of waxwings.  The first two I saw were Cedar Waxwings but I quickly found some Bohemians in the small flock enjoying a meal of crabapples.

I was not prepared for the explosion of birds from the tops of several conifers.  The massive flock, at least 2,000 birds, took flight with a whirr of wings.  It was by far the biggest group of Bohemian Waxwings I have seen on campus over the past 25 years.

When the Bohemians will arrive and how many will appear are unpredictable. The best we can say is that at least a few will arrive in Maine at some point during the winter.

Where do the waxwings we are seeing now come from?  Bohemian Waxwings nest in Alaska and northwestern Canada, nesting as far east as Manitoba.  When they fail to find sufficient food on their nesting grounds, the birds are forced to move to find sufficient food.

Most irruptive species seem to move primarily along a north-south axis.  That pattern makes sense as the distance to travel to more moderate climates is minimized.  But Bohemian Waxwings have a strong longitudinal component of their migration, flying further in an east-west direction than in a north-south direction.  Another aspect of their enigmatic nature.  Perhaps greater fruit abundance in the east explains the pattern.

During the winter, Bohemian Waxwings rely almost exclusively on soft fruits. Such fruits consist of a lot of water so a waxwing needs to eat many fruits to acquire enough fuel to maintain its metabolism.

Of course, fruits are usually frozen solid in the winter.  Melting the fruits has to be a strong energy sink.  To raise the temperature of a gram of ice one degree Centigrade requires one calorie of heat. But to convert a gram of ice at 0 degree C (the freezing point) of water to a gram of water at 0 degrees C takes a whopping 80 calories of heat.  This heat, called the latent heat of fusion, is require to change water from a solid to a liquid state.  Waxwings melt a lot of fruits in the winter.

How can one tell a Bohemian Waxwing from a Cedar Waxwing?  Both species can occur in Maine in the winter so confusion is possible.  Bohemians are grayer than Cedar Waxwings.  Even more useful are the white and yellow marks in the wing of a Bohemian, which are lacking in Cedars.  Finally, the undertail coverts of a Bohemian Waxwing are cinnamon in color, contrasting with the gray underparts.  The undertail coverts of a Cedar Waxwing are white.  Since waxwings are normally found perched in trees, the view of the undersides is the typical view for a birder.  A quick glance at the undertail coverts clinches your identification.

South Carolina Trip – II – January, 2015

By in Trip Report

This column is the second of the two recounting some of the birding my wife and I did in South Carolina in January.

After a couple of productive days in the Beaufort area, described in the first column, we headed north to Charleston.  We had a great morning at the Caw Caw Interpretive Center near Ravenel off of U.S. 17. This area is a park of 654 acres.  The area was previously three rice plantations and is now managed strictly for wildlife.  With a mix of old rice fields, natural wetlands and forest, Caw Caw hosts a diversity of birds and other animals.  A series of trails offers access to different habitats.  In short, Caw Caw is a gem.

It was a bit chilly by South Carolina standards when we were there (low 40s) and bird activity was low. Nonetheless, we compiled a nice list. Highlights included a pair of Sharp-shinned Hawks, two raucous Red-shouldered Hawks, three Tree Swallows, a Common Yellowthroat among the hordes of Yellow-rumped Warblers, three Chipping Sparrows and several alligators sunning themselves on the banks of a canal.

Our birding in the Charleston area was mainly in the adjacent town of Mount Pleasant.  A walk along the board walk at Shem Creek Park yield a Bufflehead, six Horned Grebes, four Great Egrets, three Snowy Egrets, two Tricolored Herons and a stunning adult male Northern Harrier.

A trip to Fort Moultrie was interesting historically as well as ornithologically. The sheltered water had Buffleheads, Horned Grebes, many Brown Pelicans and a Great Blue Heron.  We were rewarded for our patience as we birded the dense thickets behind the interpretative center.  Birds seen included one each of Yellow-bellied Sapsucker, Eastern Phoebe, Blue Jay, Eastern Bluebird, Hermit Thrush, Brown Thrasher, Northern Mockingbird as well as a flock of 30 Cedar Waxwings.

We toured the Fort, which affords a view of the open ocean.  The sea was angry that day picking out birds on the water was difficult.

We continued on to the small fishing village of McClellanville, just a bit south of Georgetown.  We visited friends there for nearly a week.  We went birding every day but I will cover just two of our excursions.

The first trip was to Tibwin Plantation in Francis Marion National Forest.  Access is off Highway 17 just a bit south of McClellanville. A walk of perhaps a mile through longleaf pine forest leads to a large freshwater impoundment with an observation blind. What a treat this area was.  A number of ducks were spooked by our arrival but we enjoyed great looks at Gadwall, American Wigeon, Northern Pintail and Green-winged Teal.  Two Pied-billed Grebes and lots of Double-crested Cormorants were present as well.

The impoundment had some mudflats with six Western Sandpipers and three Short-billed Dowitchers. Over 40 Greater Yellowlegs foraged in shallow water.

Two Belted Kingfishers announced their presence with loud rattles. A Red-tailed Hawk and then a Bald Eagle flew right over our heads.

The highlight of the trip was a flock of American White Pelicans. In my experience, seeing a few of these pelicans along the coast in South Carolina is expected.  I did not expect to see the 55 American White Pelicans we saw at Tibwin Plantation! The light was perfect on these birds with their bright yellow bills and gular pouches.

Unlike Brown Pelicans that dive for fish, swimming American White Pelicans cooperatively herd fish into shallow water where they can be scooped up.  It was great to see that behavior.

A three-mile hike through the Santee Coastal Reserve north of McClellanville produced a nice list. We found an Anhinga, six American Coots, two Red-bellied Woodpeckers, a Pileated Woodpecker, a Marsh Wren, two Carolina Wrens, both species of kinglets, six Swamp Sparrows and two Red-winged Blackbirds.

If you are planning a trip to South Carolina, an excellent birding resource is:

https://www.carolinabirdclub.org/sites/SC/

 

 

 

South Carolina Trip – I – January, 2015

By in Trip Report

My wife and I had the pleasure of spending ten days in coastal South Carolina in the middle of January, 2015. The birding and the temperature were great.

We flew into Charleston.  The first birds we saw were dozens of Boat-tailed Grackles foraging on the grass adjacent to the landing strip.

We departed south from the airport to the delightful town of Beaufort.  It’s a town of about 12,000 with lots of wonderful antebellum architecture. Beaufort has also provided the location for a lot of movies including The Big Chill, The Great Santini, Forest Gump, GI Jane and Platoon.  The birding was excellent as well.

Our first excursion was to Hunting Island State Park, a large, elongate tract of land. As we drove into the park, we saw a gathering of white herons, foraging in a shallow pool. Snowy Egrets and Great Egrets were outnumbered by a dozen first-year Little Blue Herons in their white plumage.  An adult Little Blue Heron and a Great Blue Heron provided some contrast.

A boardwalk onto the marsh yielded at least five Clapper Rails, calling vigorously. We were never able to see one of these secretive birds. A Willet was a nice find.

Continuing to the tip of the island, we visited the informative Visitors Center. Scoping from the pier yielded a mixed flock of loafing birds: 20 Laughing Gulls, 15 Forster’s Terns, ten Royal Terns, 20 Brown Pelicans and 10 Double-crested Cormorants.

We hiked about half a mile to the exposed beach. Erosion has been extensive in this area. A number of magnificent live oaks were corpses, killed by the encroaching ocean. An observation tower formerly well above the tide line now rises from the middle part of the intertidal zone.  We found three Red-breasted Mergansers beyond the breakers and four Northern Gannets flew quite close to shore, affording us wonderful looks.

We found a mixed flock of songbirds in the pine woods on the way back including a Red-bellied Woodpecker, an Eastern Bluebird, a Pine Warbler and several Yellow-rumped Warblers.

The following day, we checked out the Port Royal Boardwalk. A Horned Grebe, two Bufflehead, ten Double-crested Cormorant and tons of Brown Pelicans were on the water. The marsh held a Tricolored Heron as well as both egrets. A Killdeer flew overhead, calling vigorously.  A small flock of shorebirds was aggregated on a small spit of sand. We found two Willets, a dozen Ruddy Turnstones and four Dunlin there.

The adjacent woodlands produced two Palm Warblers along with tens of Yellow-rumped Warblers, a Northern Mockingbird and a Northern Cardinal.

We headed north and spent a pleasant few hours at the Donnelley Wildlife Management Area near Green Pond just off Route 17. This highly diverse area offers both wetland and upland habitats including managed rice fields, salt marsh, agricultural lands and a number of forest types.  It is managed for both game and for habitat for non-game wildlife.

An 11-mile tour covers the WMA pretty well.  We found the land birding pretty slow but I can imagine that the forests must be hopping with birds during the spring and summer.

The wetlands here most many alligators.  Always a treat to see. We also found 4 Pied-billed Grebes, a dozen Northern Shovelers, two Great Blue Herons, four Great Egrets, two Snowy Egrets and four Wood Storks.  Eight Greater Yellowlegs were foraging in the shallows of a pond.  In a marshy area, I caught a glimpse of what I thought was a coot. We managed to see the bird finally and it was a Common Gallinule, the first we’ve seen in many years.

Raptors included an American Kestrel and a Red-tailed Hawk.  As usual, Turkey Vultures and Black Vultures were almost always in sight overhead.  On to the Charleston area in the next post.

Christmas Bird Count Summaries – II – 2015

By in Christmas Count Summaries

This column is the second of two describing the highlights of recent Christmas Bird Counts (CBCs).  The CBC season spanned December 14, 2015 until January 5, 2016.

We’ll start with the Mt. Desert Island CBC, held on December 19. Although the species count was not particularly high for a coastal count (58 species), the quality of the species list was high. Counters found 17 species of waterfowl.  The most unusual were a single Eurasian Wigeon (along with a single American Wigeon) and seven Ruddy Ducks, always a good bird in the winter in Maine.

Common Loons were common (79) but not a single Red-throated Loon could be found. Both of the expected grebes were present in good numbers: 59 Horneds and 98 Red-neckeds.  Diurnal raptors were pretty scarce: a single Red-tailed Hawk, a lingering Northern Harrier and 13 Bald Eagles.

Red-breasted Nuthatches vary greatly from year to year across their broad geographic range.  This species has been relatively uncommon in Maine this winter so the 87 nuthatches found on Mount Desert were excellent.  The extensive coniferous forest on Mount Desert is favored habitat for this species.

This winter is not shaping up as a banner year for irruptive finches but this count was better than most.  Nine Purple Finches, 18 Red Crossbills and eight White-winged Crossbills were impressive. A lingering Fox Sparrow was a nice addition to the list.

The Thomaston-Rockland CBC, also on December 19, produced a fine total of 74 species. Fourteen of those species were waterfowl, none unexpected.  Two Red-throated Loons were found.  Both cormorants were found: two Greats and two Double-cresteds. One lingering Belted Kingfisher was found.

The main highlights of this count were lingering land birds. Three species of warblers were present, each represented by singletons: Pine Warbler, Yellow-throated Warbler and Yellow-breasted Chat.  Pine Warbler is a summer resident but the other two are not. The northern limit of Yellow-throated Warblers is in the Mid-Atlantic States.

Other lingering species included a Ruby-crowned Kinglet, a Hermit Thrush, 11 American Robins, two Northern Mockingbirds, one Fox Sparrow, a Swamp Sparrow and a Brown-headed Cowbird.

The Ellsworth-Hog Bay CBC on December 26 offers a nice comparison to the nearby Mount Desert Island count circle.  Ellsworth counters found 45 species.  A Northern Pintail joined 226 American Black Duck and 397 Mallards for an impressive puddle duck count.

The diurnal raptors found were a dozen Bald Eagles as well as a Sharp-shinned Hawk and a Red-tailed Hawk.  A Lincoln’s Sparrow was surprisingly late.  The only finches were 37 American Goldfinches and eight Pine Siskins.

An unusual count on January 5, the Jordan Basin Count in the Gulf of Maine yielded a dozen species.  The most abundant bird was the Northern Fulmar with 67 individuals.  Four alcids were found: two Dovekies, 11 Common Murres, seven Razorbills and an Atlantic Puffin. The gull count included 12 Black-legged Kittiwakes and a Glaucous Gull.

The Bunker Hill CBC on the Mid-coast, held on December 21, yielded 53 species. Nine species of waterfowl were found, including a lingering Ring-necked Duck.  Lingering species included a Great Blue Heron, a Northern Harrier, a Belted Kingfisher, an American Kestrel, an Eastern Bluebird, 26 American Robins, a Red-winged Blackbird and five Brown-headed Cowbirds. A Black-backed Woodpecker was a surprising and delightful find.

The Waterville CBC on December 20 yielded 51 species. The Bufflehead count of 28 was a new high for count.  Barrow’s Goldeneyes have become less common on this count; only one was found this year.

Diurnal raptors included three Sharp-shinned Hawks, three Cooper’s Hawks and two Peregrine Falcons.  Five Red-bellied Woodpeckers were notable.

The farmlands in Clinton yielded seven Horned Larks.  A single Bohemian Waxwing was found among 27 Cedar Waxwings.  Lingering species included two Northern Flickers, five American Robins, two Carolina Wrens and two Northern Mockingbirds.

Christmas Bird Count Summaries – 2015 – I

By in Christmas Count Summaries

This column is the first of two summarizing the results of some of the recent Christmas Bird Counts in Maine. The count period began on December 14, continuing through January 5. We’ll travel widely across the state today.

As you know, the weather in November and December was unusually mild. Most freshwater bodies of water were still open. We therefore expected the Christmas Counts to have some lingering species that normally would be further south. The open water could provide habitat for waterbirds that are usually forced south by ice on ponds and lakes.

The Augusta Christmas Bird Count (hereafter, CBC) took place on December 19 and produced 53 species. Common Loons have usually departed from this area by December but seven were found this year. Two Great Blue Herons were present as well. The count of 33 Bald Eagles was not too shabby. Four Iceland Gulls and a Glaucous Gull were found among Ring-billed Gulls, Herring Gulls and Great Black-backed Gulls.

Lingering landbirds included a Carolina Wren, three Eastern Bluebirds and a Yellow-rumped Warbler. Not as many lingerers as expected.

This winter is shaping up as a poor one for irruptive species, those species that occasionally move south into Maine from areas to our north. The only irruptive species were a single Northern Shrike and six Pine Siskins.

The Lewiston/Auburn CBC was held on the same day. Counters there found 51 species.

Ten species of waterfowl were detected. The more unusual sightings were 20 Greater Scaup, 35 Lesser Scaup, 20 Buffleheads and one Barrow’s Goldeneye among the 39 Common Goldeneyes. The extensive open water accounted for the five Common Loons and a Belted Kingfisher.

Lingering species included a Hermit Thrush, eight Northern Mockingbirds and a Pine Warbler. I’m sure the counters were hoping for a better showing of late-departing birds.

Like Augusta, Lewiston/Auburn hosted few irruptive birds. Three Pine Siskins were the only winter invaders found.

We’ll head to the coast now, starting with the York County CBC. This count was held on December 14. A total of 81 species were counted.

Waterfowl diversity is always high on this count; 15 species were tallied this year. The highlights included 1,083 Common Eiders and 66 Harlequin Ducks. Two loon species were present: 86 Common Loons and 13 Red-throated Loons.

We expect Great Cormorants in the winter and Double-crested Cormorants during the summer in Maine. This year, one Double-crested was found among the 39 Greats.

This count produced an excellent diversity of lingering birds. These hardy birds included nine Great Blue Herons, a Northern Harrier, four Belted Kingfishers, two Northern Flickers, two Carolina Wrens, a Ruby-crowned Kinglet, 59 Eastern Bluebirds, one Hermit Thrush, six Northern Mockingbirds, a Yellow-rumped Warbler and a Baltimore Oriole.

Two rarities were found: a Dickcissel and a Clay-colored Sparrow. A dozen Pine Siskins were the only irruptive birds.

On downeast to the Schoodic Peninsula. The Schoodic Count was held on January 1. A total of 58 species were found, including an eye-popping rarity.

Thirteen species of waterfowl were present. A single Red-throated Loon was found along with 65 Common Loons. Fifty Horned Grebes and 95 Red-necked Grebes were nice counts. A single Razorbill was found ; 21 Purple Sandpipers were seen foraging on the rocky shore.

Lingering birds included a Northern Harrier, a Belted Kingfisher, two Northern Flicker, five Yellow-rumped Warblers, a Fox Sparrow and a White-crowned Sparrow.

One Northern Shrike was the only winter invader on the count.

The highlight of the count was a Black-throated Sparrow found by Ed and Debby Hawkes and Chuck Whitney. This species is normally found in the deserts of the southwestern states and Mexico. The sighting is the first confirmed record for Maine (a 1983 record provides only sketchy details) and only the fourth confirmed record for New England. Fantastic!

The History of Bird Feeding – II

By in Uncategorized Tags:

This column is the second of two on the history of bird feeding in North America. A major resource for this column is a recent book, Feeding Wild Birds in America by Paul Baicich and co-authors.

We pick up the story in the 1941 when the Audubon Guide to Attracting Birds was published, just a week before Pearl Harbor was bombed. Roger Tory Peterson wrote several of the chapters.

Of course, the war effort prevented bird enthusiasts from spending freely on birdseed. Many found that oatmeal, bread crumbs and peanut butter served to attract birds.  By the late 1940s, several companies were formed specializing in the retail sale of birdseed.

The 50s decade was a prosperous one. Suburbs proliferated everywhere and suburbanites engaged in various home-based leisure activities, including bird feeding. John Dennis was a particularly influential person through his column “Guide to Bird Attracting” in Audubon magazine. John Terres wrote the 1953 book, Songbirds in Your Garden that further stoked the popularity of bird feeding.

Two men, Simon Wagner and Bill Engler, from competing companies joined forces to develop birdseed packaging suitable to grocery shoppers. The plastic bags allowed the buyer to seed the product before purchase. A shopper could buy food for the family and for the birds at the same time.

John Barzen was one of the first to realize that most birdseed mixes sold in the 50s were actually cheap seeds (cracked corn, millet, milo) that attracted undesirable birds like House Sparrows. European Starlings and Brown-headed Cowbirds.  Barzen found that sunflower seeds, safflower seeds and peanuts were better at attracting birds like Northern Cardinals, chickadees and jays.  The first commercial suet cakes appeared in 1958.

Bird feeding continued in popularity in the 1960s. Nyjer seed (sometimes called niger seed or thistle) was introduced as a popular attractant for finches. Most of the nyger we use is imported from Ethiopia or India.

The importation of nyger has sometimes been halted because seeds of noxious weeds are often unintentionally mixed in with the nyger. Most of the nyger seeds are now heat-treated before sale; nyger seeds are more resistant to high temperatures than the weed seeds.

In 1969, Droll Yankee introduced the tubular feeder with a number of feeding ports, perfect for feeding sunflower seeds to hungry birds.  A tubular nyger feeder was first produced in 1972.

The first Earth Day in 1970 accelerated the environmental movement, given a strong push earlier by Rachel Carson’s Silent Spring, her 1962 expose of the impacts of DDT on birds. Bird feeding took on added importance as a way to protect birds.

Birdseed was sold in bulk for the first time, often by yearly sales conducted by bird clubs or environmental groups.  Stick-on window feeders made it possible to put up a feeder just about anywhere.

Although people had been feeding hummingbirds for decades, better hummer feeders appeared in this decade.

People became more sophisticated with their bird feeding in the 1980s, often targeting particular species. This practice was made possible by a landmark study by a U.S. Fish and Wildlife Service biologist, Aelred Geis.  He conducted extensive choice experiments, determining the preferred foods of many feeder birds.

Specialty birding chains appeared in the 80s.  These included Wild Birds Unlimited, Wild Bird Centers of American and Wild Bird Marketplace.

In 1987, Project FeederWatch (PFW) was hatched.  This program was actually an expansion of the Ontario Bird Feeder Survey.  Homeowners maintain feeding stations and record feeder visits at specified times.  PFW participants are generally diligent about keeping their feeders stocked continuously.

By the 1990s, one-third of all U.S. citizens over the age of 16 fed the birds. In this decade, scientists first started to look at the impacts of feeding (increased survivorship and nutritional status, range expansions of species like Red-bellied Woodpeckers, Tufted Titmice, Carolina Wrens, House Finches and recently arrived Eurasian Collared-Doves).

 

The History of Bird Feeding – I

By in Uncategorized Tags:

In the last column, I discussed the positive benefits of bird feeders and noted that no evidence exists to show that birds become dependent on feeders. Growing and selling birdseed is big business with sales of seed and feeders exceeding two billion dollars per year.  Over 50 million Americans are involved with some level of bird feeding and observation around their homes.  Such broad interest has not always been so.

Today, we’ll look at the history of bird feeding in North America. This topic has long been a research interest of mine. This column benefits greatly from information in Feeding Wild Birds in America by Paul Baicich and others.

Bird feeding is a two-way street.  We feed the birds to help them survive but also feed to lure the birds closer to us so that we may enjoy their beauty and behavior.

We can start in 1854 with Henry David Thoreau.  In his classic reflection Walden, he writes of tossing half a bushel of unripe corn just outside his cabin and watching the various animals that were attracted to the corn, including Blue Jays and Black-capped Chickadees.

We fast-forward to 1898 when Florence Merriam Bailey began teaching bird classes to teachers in the District of Columbia. Bailey had recently graduated from Smith College and had been actively involved in battling the harvest of egrets.  These birds were being slaughtered in large numbers because their breeding plumes had become fashionable in women’s hats.

Bailey showed that nailing a few bones and suet to a tree attracted a diversity of birds.  She recommended grains and table crumbs as well.

At the same time, Elizabeth Davenport in Vermont fed the birds a diversity of seeds as well as cornbread.  She kept careful records, documenting over 20 bird species at her feeders.

Anna Botsford Comstock, a professor at Cornell University, started the Nature Study program for children.  Kids were encouraged to feed birds and make observations on them. The Nature Study program continued into the 20th century.

The venerable table feeder was in use by the end of the 19th century. Window feeding-trays appeared in the early 1900’s.  Bird feeding was encouraged by the National Audubon Society’s magazine, Bird-Lore and by two books on attracting birds by Bradford Torrey and Njelte Blanchan.

Even at this early stage of bird feeding, authors and observers noted the dual benefits of bird feeding: helping birds survive and attracting birds to enjoy them.  Suet was recommended as a most valuable food.  We concur with this advice as fat is more calorie-rich than carbohydrates or proteins. Birds store fat to fuel their migrations, their over-night shivering and other activities.

By 1910, more sophisticated bird feeders began to appear. Hans Berlepsch, a German, had begun to design bird feeders that minimized waste. His bird bell (a silo-like contraption in which seeds fell onto a tray) was one of the most popular.

Waldo Lee McAtee, a federal biologist, advocated using coconuts or tin cans with small holes as feeders.  Such feeders minimize the loss of food.  The holes could be made small to allow chickadees access but not larger birds that tended to outcompete chickadees at a feeding table.

The first suet feeders appeared at about this time. Rather than simply tying or nailing suet to a tree, people began to make suet boxes from wood or metal. Some people mixed seeds in with the suet.

House Sparrows sometime dominated bird feeders.  Many people found this introduced species undesirable.  Clever inventors produced feeders that allowed agile chickadees to get to the food but not relatively clumsy House Sparrows.

Commercial bird feeders became widely available in the 1920’s and bird feeding continued to increase in popularity.  To be sure, World War I and the Great Depression forced cutbacks in bird feeding but bird feeders were a common sight in 1940.  We’ll continue in the next column.

[Originally published on December 13, 2015]

 

The Impacts of Bird Feeding

By in Physiology

A number of readers have contacted me recently with a concern about bird feeding. Holiday travel means that our bird feeders may be depleted while we are away, depriving birds of our handouts.  Readers are asking if we are doing harm to birds by providing and then removing food.

This query requires us to answer two questions. First, do birds benefit from bird feeding? Second, do birds become dependent on bird feeders?

The answer to this first question is yes. One line of evidence comes from a technique called ptilochronology, a daunting word that refers to the rate of feather growth.  Did you know that you can see daily growth bars on a feather?  Each contour feather a bird produces has a record of how quickly it was formed.

Tom Grubb and his students used this technique to examine the impact of bird feeding. They captured Downy Woodpeckers, White-breasted Nuthatches, Carolina Chickadees and Tufted Titmice in the winter in Ohio. The researchers plucked one of the tail feathers of each bird.  The birds quickly started replacing that missing feather.

Half of the birds had access to bird feeders and the remainder were found in areas where only natural food was available. After a month or so, the birds were recaptured and their regrown tail feather was examined. The birds with access to supplemental food regrew their tail feathers at a faster rate; the daily growth bars were longer in these well-fed birds.  So, bird feeding increases the nutritional status of birds.

Margaret Brittingham and Stan Temple examined the impact of bird feeding on the winter survivorship of Black-capped Chickadees in Wisconsin.  They banded over 500 chickadees.  Some populations were given access to unlimited sunflower seeds and some populations had to depend on natural food.  Over the course of three winters, Brittingham and Temple found that winter survivorship of banded birds with access to supplemental food was 67% compared to 37% for birds without sunflower seed handouts.  That’s a pretty striking result.

The researchers found that the greatest risk to the control (unfed) birds was in the coldest months with more than five days with subzero temperatures.  Chickadees with supplemental food were also heavier than the control birds.

These results have been corroborated in similar studies done in Pennsylvania and Ontario.

Birds therefore benefit from the food we provide for them.  But is there a risk that birds become dependent on our handouts?  The answer to that question is no to the best of our knowledge.

We return to research done by Brittingham and Temple in Wisconsin.  Having shown that bird feeding increases winter survival of Black-capped Chickadees, these ornithologists set up an experiment to test for feeder-dependence.  In one area, chickadees had been given sunflower seeds continuously for several years.  In the second area, no bird feeders were ever present.  The authors took away the bird feeders from the first area where birds had been feeding on sunflower seeds for years and monitored winter survivorship of both populations.

If the population given sunflower seeds in previous years had a lower survivorship than the population with no bird feeders, one could claim that the birds in the first area had become dependent on the sunflower seeds.  But there was no difference in survivorship for the two populations.  The previously fed chickadees did as well in the following year feeding on natural food, as the unfed chickadees did that never experienced the bounty of bird feeders.

Similar studies have not been done for other North American species that frequent feeders but I expect that results would be similar.  Depending on a single source of food is risky for any winter bird.  Winter songbirds commonly range over areas of 10 to 25 acres.  Much of this area is regularly patrolled and food is taken from a number of different parts of their winter area.

[Originally published on November 30, 2015]

November Migrants

By in Migration

It’s now mid-November and the images of swallows flocking in August as they prepare to migrate are distant memories.  Yet, the fall migration still continues.  The fall spectacle is a wonderfully protracted event.

The schedule of bird migration is largely governed by food.  Migratory birds leave Maine when their preferred food is no longer sufficient. The first to leave are the aerial insect-eaters like swallows, swifts and nighthawks.  Leaf-gleaning insect-eaters like warblers, vireos and tanagers are next on the calendar. The caterpillars and other insects on which these birds depend can be found through September.  Few warblers linger into October.

Sparrows occur throughout October as the seeds of grasses and other plants are available for these ground-feeders.  Most sparrows will depart before the first snows cover their food.

The migration we are enjoying now is waterbird migration.  As long as lakes are unfrozen, these birds can find the sustenance they need.

Fall birding on lakes and ponds can be exciting.  You never know what you might see.  In late October, I took one of my two ornithology lab sections to Sabbatus Pond, a known hotspot for ducks and other waterbirds in autumn.  The first day we saw the expected Buffleheads, Ring-necked Ducks, Greater Scaup, Lesser Scaup, Ruddy Ducks and American Coots.

The next day, those same birds were present but a student pointed out a group of birds in the middle of the Pond.  Several hundred dark ducks were arranged in a line, a common behavior in Black Scoters.  Sure enough, that is what they were.  The orange bills of these birds seemed to be illuminated from within.

The flock took flight and we were able to pick out two White-winged Scoters.  Bill Hancock saw these birds later in the day near sunset.  He watched the flock fly south from the lake, making this sighting a one-day wonder.

Black Scoters nest at high latitudes on small ponds.  They winter along the coast. The hopscotch migration of these seaducks gives us a chance to see them on freshwater bodies.

In early November, a smaller flock of Black Scoters and White-winged Scoters visited North Pond in Smithfield. They were accompanied by a few Red-necked Grebes, another species that winters along the coast.

On November 6, Tom Aversa and Bruce Barker found some remarkable waterbird diversity on Sebasticook Lake in Newport.  They saw the expected freshwater species like Canada Goose, Mallard, American Black Duck and Green-winged Teal.  But, if you just saw the rest of their list, you would certainly think Tom and Bruce were birding at a coastal site.  They saw Common Eiders, Black Scoters, White-winged Scoters, probable Surf Scoters, Long-tailed Ducks, a Red-throated Loon, a Red-necked Grebe, four Horned Grebes and Bonaparte’s Gulls.  As is normally the case, these coast-bound migrants did not linger.  Striking it rich with fall waterbirds is a hit-or-miss proposition.

On that same day at Lake Josephine in Aroostook County, Bill Sheehan found a Greater White-fronted Goose among the 800 Canada Geese there.  He was also able to find two Cackling Geese, a miniaturized version of the Canada Goose.

November can be a good time to see vagrant species as well.  On November 1, Derek and Jeannette Lovitch, Kristen Lindquist and Evan Obercian found a Gray Catbird and two Orange-crowned Warblers in Portland.

On November 7, Lisa Dellwo and Bill Schlesinger found a Yellow-billed Cuckoo in Lubec.  On November 9, Don Reimer found a Blue-winged Warbler at Sebasticook Lake.

Although none have been reported this year to my knowledge, Cave Swallows occasionally appear along the New England coast in November.  The closest breeding population is in east Texas.

The big excitement this November has been the Franklin’s Gull Lake Sebasticook, present for several days.  This vagrant from breeding areas in the Great Plains provides the tenth record for the state.

[Originally published on November 25, 2015]

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