Bernd Heinrich's first book-length investigation into raven behavior, Ravens in Winter (1989) offers an in-depth look not only at a specific scientific question, but also at the process by which wildlife biologists go about answering such questions. Heinrich's curiosity is piqued when he witnesses ravens apparently calling in other, unrelated crowds to feed with them on carcasses. Since this behavior seems to run contrary to 'common sense' (which would mean keeping the food to oneself) and to known behavior among other corvids (jays and crows are not known to recruit), Heinrich sought to find out what he was seeing and why it was happening.
More than five years in the field and countless experiments later, Heinrich thinks he has an answer, the evidence and results for which are laid out in Ravens in Winter. Heinrich also published his findings in a scientific journal, but we lay readers should thank him for sharing them with us in book form (I, for one, am not a casual reader of Behavioral Ecology and Sociobiology). By expanding his process, observations and results into a narrative, Heinrich offers a fascinating window into the scientific process, while telling a good story at the same time.
Heinrich's approach to scientific research is somewhat unconventional and extremely personal. He estimates that he hauled several tons of meat into the Maine woods to provide bait for the ravens, for example, and his accounts of nearly freezing to death in the tops of spruce trees where he sat morning after morning waiting for the ravens to come so that he could document the direction they flew in from were painful to read. But he persevered, and after several years had developed a workable model which answered his original question.
If you've ever watched some jays, or a group of crows, you know how fascinatingly bizarre corvid behavior can be. Ravens in Winter is the story of what one very ambitious and interested biologist did to satisfy his curiosity about one aspect of the lives of these intriguing birds.