Bernd Heinrich - The Homing Instinct: Meaning and Mystery in Animal Migration

Text and illustrations copyright 2014 by Bernd Heinrich

All rights reserved

For information about permission to reproduce selections from this book, write to Permissions, Houghton Mifflin Harcourt Publishing Company, 215 Park Avenue South, New York, New York 10003.

www.hmhco.com

The Library of Congress has cataloged the print edition as follows:

Heinrich, Bernd, date.

The homing instinct : meaning & mystery in animal migration / Bernd Heinrich.

pages cm

Includes bibliographical references and index.

ISBN 978-0-547-19848-4

1. Animal homing. I. Title.

QL754.H45 2014

591.56'8dc23

2013042030

eISBN 978-0-547-52363-7
v1.0414

A BOUT A DECADE AGO I STARTED PULLING TOGETHER BITS and pieces on the homing topic and in 2011 had a book manuscript scheduled for publication. I was then living at camp in Maine, where I had done my fieldwork on bumblebees for years; lately my work involved feeding ravens with cow carcasses in the winter, and I then got interested in beetles that bury mouse carcasses in the summer. Soon the topic of recycling of animal carcasses of all sorts seemed more urgent than the scheduled book about getting to and living in a particular place. So, I put writing about homing on hold. By the time I again picked up my pencil, it seemed as though everything I thought of or had an interest in had, in one way or another, started to have a bearing on home and homing. In the meantime I had also been confronting personal issues of homing, and they seemed to take on increasingly similar forms to what I was reading about in animals.

I had already left my academic position in Vermont and wanted to return home to live in Maine, possibly in the home to which I had bonded strongly as a child. I had planted a row of trees there about thirty-five years ago. Those trees, now huge, brought back many memories related to them. They reminded me of my father, who had liked them, probably because he had strong feelings for a row of chestnut trees that also lined the way to his old home in the old country that he had often talked about. Because I had written a book about my father, and not also one about my sisters or my mother, I had come into the disfavor of both. There had been parent-offspring conflict before my mother died, and then the house stood empty. So then there was also sibling rivalry over the estate. It seemed like being in a real-life situation of the sociobiology theories, in an almost perfect rendition of a naked mole rat colony where one of the family finds a big tuber, and the others claim it as theirs, and then a vocally assertive member establishes herself as the matriarch. I realized then that the difference between what can happen to a human and to a naked mole rat family is mainly one of terminology. This thus provided the topic of home and homing a much wider perspective.

Our passionate preoccupation with the sky, the stars, and a God somewhere in outer space is a homing impulse. We are drawn to where we came from.

Eric Hoffer

With all things and in all things, we are relatives.

Native American (Sioux) proverb

I LEANED ON THE SHIPS RAILING AT THE STERN, A TEN-YEAR-OLD boy with virtually no notion of where my family might be going. I heard the deep roar of the engines, the whine of the wind, and the rush of the churning water. I felt adrift, as though carried along like a leaf in a storm, feeling the rocking, the spray, and the endlessness and power of the waves. I had no notion that we were among multitudes who had made hard decisions to court the great unknown, or any clear idea of why my family had left the only home Id known in a forest in Germany. The only picture of what our new home might be was that we might find magical hummingbirds, and fierce native tribes armed with knives, bows and arrows, spears, and tomahawks.

Security for me was the memory of where we had come from, specifically a little cabin in the woods and a cozy arbor of green leaves that enclosed me like a cocoon where I could see out but nobody could see in. It meant a feeling of kinship with the tiny brown wren with an upright stubby tail that sang so exuberantly near its snug feather-lined nest of green moss hidden under the upturned roots of a tree in a dark forest. I had in idle moments in my mind inhabited that nest. I found, too, the nest of an equally tiny long-tailed tit. This little birds home was almost invisible to the eye because it was camouflaged with lichens that matched those on the thick fork of a tall alder tree where it was placed.

The ocean all around was a spooky void. But then, after several days at sea, a huge white bird with a black back appeared as if out of nowhere, and it followed us closely. I saw its dark expressionless eyes scanning us. It was an albatross. It skimmed close over the waves and sometimes lifted above them, circled back, and then picked up momentum to again skim alongside our boat. It followed us for hours, maybe even days.

The albatross was big and flew without beating its wings. Years later I wondered if, even in the featureless open ocean where so much looked the same every hour and every day, it may have known where it was all along. How do we find our home and recognize it when we find it? These questions were inchoate then, but given the examples of other animals, they put many ideas of home and homing in context.

Later, as a graduate student, I read that pigeons could return home to their loft even when released in unfamiliar territory, and that some other birds could navigate continental distances using the sun and the stars. There were few answers to how they did it. But I read about researchers at Cornell University who attached magnets to the heads of pigeons and got them all confused. Donald Griffin, my scientific hero (who had discovered how bats can snatch silent moths out of the air in a totally dark room that had wires strung all over the place), was releasing seagulls over forest where they could never have been before and then tracking the birds flight paths by following them in an airplane. Most of his birds turned in circles before some of them flew straight, although why was not clear. Searching for a thesis problem to work on, I wrote to ask him if birds passing through clouds might keep in a straight line by listening to the calls flocks make while migrating. He replied in a long, thoughtful letter to let me know that this idea was too simplistic, and that one should not discount much more complicated mechanisms. That was excellent advice. I did not then have the means to solve any of these puzzles, but over the years I have kept in touch with the evolving field of animal navigation and its relevance to the need for a home.

For other animals and for us, home is a nest where we live, where our young are reared. It is also the surrounding territory that supports us. Homing is migrating to and identifying a suitable area for living and reproducing and making it fit our needs, and the orienting and ability to return to our own good place if we are displaced from it. Homing is highly specific for each species, yet similarly relevant to most animals. And the exceptions are illuminated by the rule.

The image of that albatross took on more meaning decades later, after I learned that the species mates for life and returns to the same pinpoint of its home, on some island shore where it was born, perhaps fifteen hundred kilometers distant. During the years when it grows to adulthood it may never be in sight of land. Seven to ten years after having left its home, it returns there to nest. It chooses to go there because of its bond. When a pair eventually have a chick in a nest of their own, each parent may travel over fifteen hundred kilometers of ocean to find a single big meal of squid, and after gathering up a full crop, it then flies home in a direct line; it knows where it is at all times.