Now, as newer suburban continue to mature, the owl habitat is steadily expanding. As the farms have been abandoned, the new neighborhoods that replaced them have planted trees, he said. If you wait long enough, the barred owls are going to expand their territory, as the trees start to grow up in the newer suburban neighborhoods.
Other mysteries of urban owl life are beginning to emerge, including the question of what it is that city birds most like to eat squirrel or cardinal, crawfish or koi? In the last couple of seasons the researchers have installed video recorders in some of the nest boxes, and Cori Cauble, one of Bierregaards graduate students, has been researching a thesis on the owls food habits and how they compare to owls in the wild.
Before the video cameras, the researchers had noted the prominence of bird feathers in the nest boxes, but were unwilling to draw any conclusions because they noted that feathers were more likely to be left and preserved from kills than other kinds of remains. The videos of owl home life answered the question.
We scaled back our estimation on how important birds are in their diet until the first day we had a video camera in a box: they brought in eight prey items and four were birds. That result has held for two years we have had cameras in four or five different nests. They have diverse diets, depending on territory, he noted. We have one nest we call the sushi box because they bring in so many fresh fish, but even there the owls bring in a lot of birds.
All-in-all, the researchers think a picture is emerging of barred owls that are nearly as happy in cities as people are, though like the humans, they hate and fear the traffic, and living space is at a premium.
The biggest source of mortality in an urban environment is flying into cars, Bierregaard noted. Weve had a couple die of diseases, but for most of the birds that we have had
|Contact: James Hathaway|
University of North Carolina at Charlotte