Bernd Heinrich’s Homing Instinct was a great book to read in the early fall, when Northfield’s skies are full of geese and ducks wending their way south – after long, leisurely stops in our ponds and creeks. The book’s subtitle – “meaning and mystery in animal migration” – suggests that Heinrich will explore animals’ instinctual seasonal movements, and indeed much of the book does deal with that topic. In the first section – “Homing” – Heinrich tells staggering stories about how various birds, insects, and mammals find their way over distances that are extraordinary on both their own scales (bees that thoroughly master acres and acres of forest and field) and on global ones (eels that breed in the Sargasso Sea but live most of their lives in coastal waters in North America and Europe).
The science that underlies human understanding of these animals’ movements is amazing, but the animals’ own comprehension of the world is far more so. Loggerhead turtles apparently navigate incredibly long distances by reading tiny changes in the earth’s magnetism. I was impressed by the Heinrich’s stories, by scientists’ efforts to comprehend animal migration, and by the animals’ own skills, but I was also depressed by the realization that by wrecking the planet, we humans are directly and indirectly destroying animals (and of course plants and other kinds of life) that are so much more complex and mysterious that we do or perhaps ever will know. (Here my wonderings ran to bison, which in their herds before the Great Slaughter may or may not have migrated seasonally or on another schedule across hundreds or thousands of miles of North America.)
The book’s subtitle is misleading though in that much of the second half of the book concerns animals’ homes, not their movements. Here, Heinrich deals with all kinds of birds’ and insects’ nesting behavior and structures as well as a few mammals (pointing out that very few “higher” mammals actually build homes!). The center of this second section – “Home-making and Maintaining” – is a long, engrossing description of Heinrich’s own efforts to understand the spiders that lived in his Maine cabin. Their web homes are both shelters and tools, which – as Heinrich shows – the spiders used in sophisticated and, frankly, terrifying ways. This chapter – like the “Sun, Stars, and Magnetic Compass” chapter in the first section – are standout natural-history essays.
In the book’s third and last section, Heinrich changes register dramatically, writing at length about his own “homing instincts” for what sounds like a gorgeous patch of Maine woods. I was at first put off by this change from animal to human life, but gradually, Heinrich shows how his drive to live there, and not somewhere else, is continuous with the instincts and drives of the animals he’d discussed earlier in the book. This section is a lovely way to bring the book home.