WHITE FEATHERS

A search for the answer to a seemingly trivial question—why do tree swallows line their nests with white feathers?—reveals much about the nesting behavior of these wild birds but even more about the lifestyle of a dedicated scientist.

Heinrich (Emeritus, Biology/Univ. of Vermont; The Naturalist's Notebook: Tracking Changes in the Natural World Around You, 2017, etc.), a prolific author and naturalist, is no casual observer of nature. Each spring from 2010 to 2018, the now-retired professor sat quietly for hours watching tree swallows, counting, measuring, recording, and conducting experiments. He focused on a single pair of tree swallows, first in Vermont and then from his cabin in Maine. Rising sometimes before dawn, he recorded to the minute the birds’ behaviors: “Finally, at 6:46 a.m., he landed on the box, peeked in, and flew back up to perch quietly on the locust tree until 7:12 a.m.” Heinrich kept precise tabs on when the migrating birds returned, mated, built a nest, and laid eggs as well as when the eggs hatched, how often the chicks were fed, and when they fledged. The affinity of tree swallows for white feathers puzzled him, and he conducted experiments with feathers of various sizes and colors, even with strips of toilet paper when no feathers were available. The answer to the white feather puzzle he offers here is appealing but one that he admits needs further testing. As he writes, “eight years observing ‘my’ swallows’ behaviors related to white feathers yielded both fascination and frustration.” The author provides more information about the nesting behavior of tree swallows than most general readers will want to know, but the picture that emerges of a naturalist at work is impressive. Illustrations include eight pages of his own black-and-white close-up photographs and a scattering of delightful drawings of trees, nests, birds, feathers, and eggs.

Definitely one for dyed-in-the-wool bird lovers.