small prey and also scavenge from carcasses opened by other carnivores. Adult pairs stay year-round in their territories and defend carcasses they find there. Wandering juveniles are excluded from the feasts, unless they band together to overpower the resident adults. They “gather the troops” by joining communal roosts at night, and naive hungry birds can get food by tapping into information of food resources, by following those that take the initiative to leave predawn to fly to a food bonanza such as a deer or moose carcass that they had discovered or fed from previously. The problem is, there is a lot of competition at the carcass, and not all of the crowd of dozens to a hundred or more can be assured continuous access to the few available feeding spots. But there is a solution: Those dominant birds that can get at exposed meat haul off as much as they can and hide it, to retrieve later when the gang may have removed most of the meat. And those that couldn’t get through the crowd? They too have a solution: They closely observe where the dominant birds hide “their” meat, wait until these cachers are out of sight, and then recover the other’s cache either to eat the food right there or hide it elsewhere. In turn, a bird trying to hide food avoids potential cache-raiders and positions itself to be out of sight from them. In the intense social interactions among the birds at carcasses in the winter, those that can best anticipate the intentions of competitors (and the potentially dangerous carnivores also at the carcass) are most likely to be reliably fed. Such a scenario, where one or a few individuals may try to control a resource in a crowd, is currently a prime scenario for consciousness or what is known among animal behaviorists and biologists as “theory of mind.” This is a much different sort of mental facility than memory, and ravens, although possibly the most intelligent of birds, do not exhibit impressive long-term memory for cache locations. Cache locations are remembered for two weeks, and a month may be their limit (Heinrich 1999). But given the ravens’ lifestyle and their food, that’s probably sufficient.
Each animal’s lifestyle has its own unique opportunities, and requirements and constraints. That of the gray jay (Perisoreus canadensis) offers intriguing contrasts to that of the raven. These fluffy, diminutive members of the crow family look to me like oversized chickadees. They are everything a crow or a raven is not: tame to the point of seeming friendly, vocally muted, restrained. They are silent fliers who glide on mothlike wings. They never aggregate in big crowds, generally don’t feed on carcasses, and have a soft look and none of the raven’s or the crow’s bold sharpness of eye. Instead of flying from you on rapid wingbeats ripping the air, gray jays more typically silently glide up to you. Gray jays, formerly called Canada jays, are the north woodsman’s endearingly named whiskey jacks, and camp robbers, who are always looking for a handout. That is why they are so intriguing; they seem to have no visible means of support. Yet, they live in what appear to be barren spruce forests, far from human handouts. They live only several miles from my cabin in Maine, and I’ve met them in willow thickets on the Noatak River on the North Slope in Alaska. They are one of the very few birds that survive year-round in the northernmost taiga, breeding as early as March, often two months before the snow has melted. How do they manage it? The answer to this bird’s riddle probably has less to do with either superior memory or intelligence and a lot more to do with their saliva.
William Barnard, an ornithologist from Norwich University who studies a small population of these birds in Vermont’s Victory Bog, tells me that their saliva is “amazing stuff.” Most spit is designed to ease the food down the esophagus. It must be slippery and non-sticky. This birds’ saliva coagulates on contact with air, to become viscous and sticky. In short, once extruded, it becomes glue. It is a very important glue to gray jays. These birds