Category Archives: Citizen Science

September brings spike in bird migration

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Hans Toom/Pixabay • Few warblers make as great a journey as the blackpoll warbler. This small songbird makes a roundtrip flight of 12,400 miles for its seasonal migrations each year.

September’s arrival puts fall migration into sharp focus. The birds that returned this past spring — the warblers, vireos, tanagers, grosbeaks, flycatchers, hawks, hummingbirds and many more — have begun or are beginning to make their way back to the locations where they will spend the winter months far from the cold, bleak conditions over most of North America.

Every morning as I leave for work I hear the buzz of hummingbird wings. When I return in the evening, I am often greeted by the scolding calls of red-eyed vireos from the woodlands around my home.

Some of these birds migrate out of the tropics every spring to avoid competition. Others find North America a land of abundant, albeit temporary, resources. This land of plenty offers a wealth of insects, seeds, fruit and other nourishing, nutritious food to help parent birds keep their strength while they work to ensure their young thrive. Of course, once the bountiful period concludes, they return to the tropics of Central and South America to winter. Those that do so successfully will make the journey back to the United States and Canada in the spring. It’s an ongoing cycle, repeating year after year, season after season.

The phenomenon of migration isn’t exclusive to the neotropical migrants of the New World. Birds in other parts of the world migrate, too. Waterfowl, shorebirds and raptors are among some of the families of birds that stage impressive migrations.

Photo by Jonathan Cannon/Pixabay.com • The Arctic tern outdoes all other birds when it comes to migration. These seabirds journey from their Arctic nesting grounds to spend the winter around the Antarctic, a journey of some 50,000 miles a year.

The Arctic tern, for example, truly takes migration to extremes. This small seabird travels each year from its Arctic nesting grounds to the Antarctic region, where it spends the winter months. Put into terms of mileage, the Arctic tern can travel about 50,000 miles in a single year. For a bird with a body length of about 15 inches and a wingspan of about 28 inches, this incredible migration is an astonishing feat. These statistics permit the Arctic tern to easily lay claim to the title of champion migrant among our feathered friends.

According to the website for National Geographic, Arctic terns face a serious threat from climate change. In a profile on the tern at its website, National Geographic warns that Arctic terns are projected to lose 20 to 50 percent of their habitat due to the temperature changes linked to climate change. They also face loss of habitat due to encroachment by human activities such as oil drilling.

The ruby-throated hummingbird, a favorite of many bird enthusiasts living in the eastern United States, makes an impressive migration each year. Just to reach the United States, these tiny birds undertake a strenuous journey. They leave their wintering grounds in Central America to return to the United States and Canada for the nesting season. Most of these tiny birds, which are barely four inches long, make a non-stop flight of more than 500 miles across the Gulf of Mexico. The journey can take almost an entire day. With the end of summer, the entire population of ruby-throated hummingbirds, increased by a new generation of young birds, makes the Gulf crossing for a second time in a year to return to the American tropics for the winter months.

Photo by Bryan Stevens • A ruby-throated hummingbird perches at a feeder for a sip of sugar water.

Among North America’s buteo hawks, which includes raptors such as red-shouldered hawk and red-tailed hawk, the broad-winged hawk stands out as a dedicated migrant. These hawks form flocks that at times number in the hundreds or thousands as they sail and glide on thermals rising over various mountain ranges. These hawks and other raptors are well-known in the region for migrating past the Mendota Fire Tower in Southwest Virginia every September and early October.

The broad-winged hawk’s counterpart in the western United States is Swainson’s hawk, which shares the broad-winged hawk’s inclination for migrating in large flocks. Swainson’s hawk is named for William Swainson, the famous 19th century English naturalist for which Swainson’s thrush is also named.

The hooded warbler, my favorite member of the migratory New World warblers, migrates back to Mexico and Central America for the winter months after nesting during the spring and summer in a range concentrated in the southeastern United States. The males, after going quiet in late summer, have started singing on occasion from the shaded woods around my house. I think this has more to do with restlessness as they prepare for to depart on a migration flight that will take them to the balmy Caribbean, Mexico and Central America while we shiver through the months between October and April. It’s not a migration of an incredible distance, but it’s still quite an accomplishment for a bird only five inches long and weighing less than half an ounce.

Another warbler is a true migratory champion. Few warblers make as great a journey as the blackpoll warbler. Instead of migrating over land, this five-inch-long warbler undertakes a two-stage migration. The first half of the migration is a non-stop flight of about 1,500 miles. Every fall, these tiny birds fly over the Atlantic Ocean during this part of their migration, departing from Canada or the northern United States and not stopping until they reach various locations in the Caribbean. There they will spend some time recovering from the exhausting first half of their journey before they continue their way to such South American countries as Colombia and Venezuela. Once again, during the time they spend flying over open ocean, these tiny warblers do not feed.

Fall’s a great time to witness the variety of avian life. Look for some of these migrants passing through your yards, gardens or favorite birding spots.

For those wanting suggestions for seeking out migrating birds, the linear trail in Erwin, Rocky Fork State Park in Flag Pond and Limestone Cove Recreation Area are some good bets.

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To ask a question, make a comment or share a sighting, email me at ahoodedwarbler@aol.com. 

Reader from Utah shares story about pine siskin rescue

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PineSiskin-Utah

Photo Courtesy of Fred Bergold • This pine siskin recovered after crashing into a window at the Utah home of Fred Bergold.

A recent email reminded me that some of the birds that visit us during the winter range far beyond our yards and gardens here in Northeast Tennessee.

I received an email from Fred Bergold, a reader who resides in Utah.

“This little warbler flew into our window,” Fred explained in his email, which arrived with photos attached. “My wife picked it off the deck and held it for about half an hour.”

The kind treatment worked. “When it got its bearings back, it flew to the top of our Colorado green spruce,” Fred wrote.

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Photo by Bryan Stevens • Pine siskins feast on thistle seeds at a feeder.

“We feed the local wintering birds black oil sunflower seeds, which many species seem to like,’ Fred continued. “We live in Fruit Heights, Utah, just north of Salt Lake City.”

When I looked at the photos Fred provided, I realized that the bird in question wasn’t one of the warblers but a species of small finch known as a pine siskin. I replied to Fred’s email and offered a quick lesson in distinguishing pine siskins from warblers and other small songbirds.

I informed Fred that siskins usually travel in flocks and that they love feeders with sunflower seeds.

I also shared with him that I’ve gotten to travel to his home state of Utah twice since 2003. Getting to see some western species — American dipper, lazuli bunting, western tanager, violet-winged swallow — while visiting the state produced some memorable birding moments.

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Photo by Bryan Stevens • A Pine siskin in a spruce at Carver’s Gap on Roan Mountain.

Winters, no matter where one lives, can decrease the variety of bird species one sees on a daily basis. I often find myself hoping for the excitement produced when flocks of “irruptive” finches not often seen in the area expand their range into the region. In addition to pine siskins, birds such as evening grosbeaks, purple finches, common redpolls and red crossbills represent a few of these northern finch species that occasionally stage massive migratory movements, or irruptions, into areas far outside their typical ranges.

These finches are not the only birds to stage these periodic irruptions. The website birdsource.org identifies several non-finch species — red-breasted nuthatch, Clark’s nutcracker, bohemian waxwing, black-capped chickadee and varied thrush — that undertake periodic winter irruptions. Two of these northern finches — the pine siskin and the red crossbill — are sporadic summer residents on some of the higher mountains in our region.

Siskins-OnGround

Photo by Bryan Stevens • A flock of pine siskins carpet the ground beneath some feeders as they forage for food.

These irruptions are not usually motivated by cold or severe weather. The absence of a favored food source on a bird’s normal winter range is usually a trigger for an irruption. Birds, such as pine siskins, will fly farther than normal in a quest for reliable food sources. Not surprisingly, well-stocked feeders often attract their attention.

The pine siskin belongs to a genus of birds known as Spinus, which includes three species of goldfinches and more than a dozen species of siskins, many of them native to Central and South America. Only one species — the Eurasian siskin — is found outside of the New World. Other siskins include the black-capped siskin, hooded siskin, red siskin, black siskin, Antillean siskin and Andean siskin.

GoldfinchBABE

Photo by Bryan Stevens • The American goldfinch is a relative of the pine siskin, and the two species often associate with each other at feeding stations.

Siskins often associate with American goldfinches. In shape and size, the two birds are extremely similar. Unlike goldfinches, however, siskins display extensive streaking on their back and breast. The bill of a siskin is sharp and pointed. Overall a drab brown in coloration, siskins also show some surprisingly bright yellow coloration in their wings and tails. Although sociable, individuals can display some irritable tantrums when competing for prime space at feeders.

Some people quickly discover that a large flock of pine siskins is quite a drain on the daily allotment of feed provided for backyard birds. For such small birds, they have large appetites. Siskins are also extremely tame and can often be approached quite closely. A few years ago during a particularly frigid cold snap, I succeeded in luring a pine siskin to land on my gloved hand, which held some sunflower seeds. Needless to say, it was a very memorable, intimate moment.

In addition to this unusual tameness, siskins are extremely vocal birds. These birds have a shrill trill that sounds almost mechanical to my ears. Large flocks also produce a constant twittering noise as they perch in trees or on feeders.

Next month will offer an opportunity to participate in the annual Great Backyard Bird Count, which is a free, fun, and easy event that engages bird watchers of all ages in counting birds to create a real-time snapshot of bird populations. Recording visiting birds such as pine siskins is an important component of the GBBC. Participants are asked to count birds for as little as 15 minutes (or as long as they wish) on one or more days of the four-day event and report their sightings online at birdcount.org. Anyone can take part in the Great Backyard Bird Count, from beginning bird watchers to experts, and you can participate from your backyard, or anywhere in the world. The 21st annual GBBC will be held Friday, Feb. 16, through Monday, Feb. 19, 2018. Please visit the official website at birdcount.org for more information. I’ll also focus on the GBBC more in upcoming columns, including information about activities planned at a local park.

Evening_Grosbeak_Ted_Schroeder_OR09

Photo by Ted Schroeder/Great Backyard Bird Count • Evening grosbeaks may be more common on this year’s GBBC, according to early reports on the movements of these large, colorful finches.