One of the marvels of avian biology is the adaptations that allow birds to live through brutally cold winter weather. Birds use a multi-pronged approach. To understand the ways that birds accommodate the cold, we will delve into some physics, geometry and biochemistry. Like mammals, birds maintain a constant body temperature in the face of varying environmental temperature. In the winter, birds lose heat from their surface to the cold air or water. To keep their temperature constant, their cells must produce enough heat to balance the heat that is lost to the environment. Virtually all of a b ..read more

The 122nd Christmas Bird Count (CBC) sponsored by the National Audubon Society is now history. On a day between December 14 and January 5, groups of birders spread out to census all the birds in a circle with a 15-mile diameter. There are over 2500 CBC circles in North America with others in Central America and South America. This annual census is a powerful tool in assessing the changes in winter bird abundance. This column is the first of three in which I will review the highlights of some of the Maine CBCs. Today we’ll look at four Mid-coast sites and two inland sites. The Augusta CBC on D ..read more

The Endangered Species Act has been instrumental in the conservation of many bird species as well as other organisms. The ESA was enacted in 1973 by the U. S. Congress in a resounding fashion.  The vote was 92 for and none against in the Senate and 390 for and 12 against in the House. Truly a bill with bipartisan support. To be sure, business interests and some Republican officeholders fight to weaken or eliminate the ESA but it has withstood those challenges. Over 80% of Americans support the ESA. The ESA is the most comprehensive legislation for the protection and recovery of endangere ..read more

Running a marathon is a great test of human endurance. World-class marathoners raise their metabolic rate five times their resting metabolism as they traverse the 26.2 miles in about two hours. In what seems to be a never-ending effort to test endurance limits, even more arduous competitive events have been created. Toss in a 2.4 mile swim and a 112-mile bike ride and you have the Ironman Triathlon. Other athletes run ultramarathons, long-distance races up mountains and races to see how far one can run in 24 hours. For all of these events, the metabolic rate tops out at five times the resting ..read more

Late this spring (https://web.colby.edu/mainebirds/2021/05/31/common-bird-names-and-eponyms/), I wrote about a movement to remove people’s names from the common names of birds. In large part, this movement is driven because some of these eponyms honor people with disreputable pasts. Most recently, McCown’s Longspur was changed to Thick-billed Longspur because McCown was a Confederate leader and advocate of slavery. Rather than review every eponym to see if the person has skeletons in his or her closet, advocates are arguing for the replacement of all eponyms with an adjective that describes s ..read more

Life is never simple. When we try to solve a problem, our solution may entail unexpected side effects. Social scientists call such effects unintended consequences. Just listen to a litany of negative side effects of a new drug in a TV commercial. The drug may well help a patient but at the risk of incurring undesirable side effects. Sometimes an unintended consequence can be helpful. Aspirin relieves pain but it also has anti-coagulant properties that can reduce the likelihood of heart attacks and lower the severity of strokes. Natural communities are ripe for unintended consequences because ..read more

The nesting season has come to a close for most of our Maine birds. That means that many of our migratory breeding birds will be departing soon for their wintering grounds. Some have already left. Our swallows and many of our flycatchers are among the earliest migrants. We’ll have to wait until 2022 to see barn swallows and cliff swallows. Warblers, vireos and thrushes will be streaming south throughout September.  The sparrow migration will pick up speed in October. Migration, even for short distances, is an arduous task that demands a high expenditure of energy.  Two other events i ..read more

One of the big stories of this bird breeding season is a mysterious epidemic that has lead to widespread deaths of songbirds. These deaths have been reported from Maryland, Virginia, West Virginia, Delaware, Pennsylvania, Kentucky, Ohio and Indiana. Species that are particularly susceptible are blue jays, American Robins, European Starlings and Common Grackles. Juvenile birds are disproportionately affected. Birds that are infected show swollen eyes, often with crusty deposits around the eyes. Some birds tremble, twitch or stagger around, suggesting some neurological damage. So far, the epide ..read more

We see great variety in the shape, location and size of bird nests in Maine. The simplest nests are scrapes on the forest floor, fields or beaches.  The nest of a Killdeer is a good local example.  The female lays four eggs in a nest scrape just big enough to contain the eggs.  As you would expect, the eggs are well camouflaged.  In the woods, American Woodcocks and Whip-poor-wills create nest scrapes for their eggs.  For most species that create nest scrapes, little effort is made to line the nests with soft material.  Piping Plovers make a similar sort of nest ..read more

This month is the height of the nesting season for Maine birds. All of our birds have laid eggs and many of those have hatched, The eggs that a female lays are, of course, vital for successful reproduction. Getting the chicks hatched and, for many species, feeding the young are critical steps in adding new birds into the population of each species. Aside from the efforts of the parents, nothing is more important in breeding success than the nest. A nest is an intricately designed, multi-functional structure. A nest is more than a cup to hold the eggs. The nest facilitates efficient warming of ..read more