Fall Migration - A Scientist's Activities

August to October

Sometimes scientists use boats to capture caribou at river crossings during fall migration. This usually occurs near Old Crow village in the Yukon. This is an easy and inexpensive way to put more radiocollars on caribou, provided the caribou come to the crossings, which isn't always the case. Scientists also cooperate with local hunters to gather biological samples from caribou that are harvested by villagers for food. If the samples show the caribou are fat and healthy, it usually means the pregnancy rate will be high and many calves will be born the next summer. Skinny or lean caribou mean that productivity will be lower.

Otherwise, caribou scientists usually don't do much fieldwork during fall migration, but they stay busy in their offices analyzing data from the summer. Scientists also go to meetings and work with the public to set hunting seasons for the caribou. Fall is also a likely time for counting the census photos. Scientists have to lay out the photos, draw lines so caribou on overlapped photographs only get counted once, and then laboriously count the caribou one by one. They use magnifiers, grid lines, and tally counters to keep track of the thousands of caribou. It's a big job to count over a hundred thousand caribou!