Shockingly early mornings; cold, tedious hours of observation; occasional breakthroughs. Anyone who has wondered what biology field research is like will find a striking description of it in John and Colleen Marzluff’s account of their work on ravens.
Dog Days, Raven Nights (Yale University Press) relates the couple’s long Maine-winter days in the late 1980s spent stalking ravens. Fortunately, the Marzluffs’ experiences, early in their careers, were so novel to them that they took copious notes.
“It was such a big adventure, and as we met people in the first few weeks of our getting there I thought, ‘I have to write this down,’” says Colleen Marzluff in her husband’s office at the University of Washington, where he is a professor of wildlife science. In the fall of 1988, at Northern Arizona University, John M. Marzluff, now a well-established expert on corvids and the author of four books, including In the Company of Crows and Ravens (Yale, 2005), was a freshly minted postdoctoral researcher. Colleen Marzluff was an experienced field-research technician. Married three years, they had met on campus. He had been investigating pinyon jays, relatives of ravens and frequent victims of their nest-robbing. She had been plumbing the mysteries of jays’ and nutcrackers’ extraordinary spatial memories.
Off the couple went to work in mountainous western Maine with the brilliant, idiosyncratic biologist Bernd Heinrich. Under his direction, they would extensively study the winter ecology of the raven, at that time “just yielding to scientific scrutiny,” they write.
Happily, the Marzluffs recalled the wisdom of an early dog-sled designer: “A smart man never carries on his back what he can put in a sled.” They set about training Siberian huskies, which proved a blessing once local supporters brought them carcasses of animals that ravens love to eat: chunks of cow and draft horse, and sometimes deer or moose roadkill. Wolves, which are near-relatives of huskies, and ravens have long been known to assist each other in hunting; now the huskies helped the Marzluffs stalk their ravens. The dogs also kept the couple company during long stretches of observing the birds, as the Marzluffs ran Heinrich’s experiments.
Those experiments were designed to deterine why ravens in the snowy Maine woods seemed to tell other ravens in mass night roosts about their finds of carcasses and other food bonanzas. In evolutionary terms, self-interest would seem to dictate keeping quiet.
Were all the barks, clucks, gurgles, hoots, rattles, and whoops of the ravens just cries of excitement over the prospect of a feed? Were young ravens recruiting one another to throw older, feeding ravens off the top of the raven food chain? Or were they merely screaming and prancing like teenagers at a disco?
Eventually the researchers concluded that ravens were indeed sharing information about food sources. Those social acts made evolutionary sense because joint feeding optimizes survival.
The quest for explanations kept the Marzluffs in the field for three years, a period when they formed various kinds of partnerships: student-mentor, husband-wife, and human-dog.
“Each has taught us so much,” they write. So did the human-raven relationships, and the social bonds with local people they encountered in an area of rural Maine that few outsiders knew. In thick, damp woods, the couple found a welcoming social world.
“We literally stepped into a family from day one,” says John Marzluff. They became regulars at local holiday gatherings.
Heinrich’s reputation and support in the area, even while he was away at his research-and-teaching post at the University of Vermont, helped his recruits. Their mentor, who as a child had come to the area from Germany after World War II, was a woodsman, an expert on Bumblebee Economics (the title of his 1979 Harvard University Press book on the insects’ ecology), and a world-class ultramarathon runner (thanks to chasing his research prey up and down hills and through forests) who had turned his attention to corvids.
Not your run-of-the-mill neighbor.
Local residents, curious to see what Heinrich was up to this time, flocked around him and the Marzluffs when they constructed a big aviary in which to raise captive raven chicks. Says Colleen Marzluff: “They’d say, ‘Really, you’re going to build a huge cage?’ ”
“Yeah,” her husband pipes in, “and ‘When do you need us?’ ”
Against the dying orange, gold, and scarlet glow of maple and beech foliage, the Marzluffs underwent a trial by fire. In sections of the book that are coded to indicate which of the two is the author, Colleen Marzluff, now far away from academe, frankly addresses the tensions, while her husband, long an academic, takes it up more tentatively.
She writes: “When Bernd visited, we looked for intellectual stimulation, field assistance, and appreciation. We got plenty of the first but none of the last.”
“He expected us to work only with aviary experiments, not to reinvent his understanding of the entire raven winter social system,” she adds. But she and her husband became bored with simply observing captive ravens all winter long, and so they ventured out to explore the raven world.
Eventually, disagreements arose over who would be designated as primary author when fieldwork was written up.
In his office, John Marzluff says: “I hope people who aren’t in the sciences will understand that our book is about a long training period, basically.” That, and the frustrations of doing a senior colleague’s experiments when you have ideas of your own. “You are ready to go when you have the Ph.D.,” he says.
Still, the Marzluffs acknowledge how important Heinrich’s mentoring was: “Although we did not always see eye to eye on the daily grind of science,” they write, “we remain respectful friends and valued colleagues.” Heinrich, in a foreword to the book, says their account makes him “understand and appreciate much more about their personal adventure and unique experiences.” He writes: “The good times and often challenging times are laid bare.”
“We couldn’t have written this book when we left there,” John Marzluff says, “and we couldn’t write it for a long time after that.” Colleen Marzluff interjects that her husband “can look at it in hindsight, too, because now he’s in the hot seat himself, with doctoral students of his own.”
John Marzluff’s continuing research on corvids takes him—or his trusty doctoral students—to areas near his home, northeast of Seattle; to the Olympic Peninsula; to Arizona; and around the campus of the University of Washington.
He has examined issues such as corvids’ food fears, and increasingly he works with brain scientists at the University of Washington Health Sciences Center. With their help, he has been able to begin to understand what the brains of birds can reveal about their senses of sight and smell and their social world.
More contentiously, he has speculated about corvids’ culture, or whatever the appropriate term is for what happens when the birds combine their own instincts with behaviors they learned from others of their species.
As with any nonhuman animals, whether the social interactions of corvids can be considered an indication of their having a culture is “always controversial,” says John Marzluff, because anthropologists, biologists, and humanists all have different definitions of the term. Certainly ravens and other corvids, like humans, are social animals. Disentangling nurture from nature, he says, is a complex process.
“There’s more and more evidence of social learning and traditions in corvids,” he says. “You can call that culture, if you’re a biologist, without a problem.”
