by Paul Hess
Most of us didn’t hear about it, but a female Burrowing Owl nested twice and successfully fledged seven young within the same breeding season—approximately 1,100 miles apart, first in Arizona and then in Saskatchewan.
This remarkable occurrence was documented by Geoffrey Holroyd and Helen Trefry of Environment Canada and Courtney Conway at the U.S. Geological Survey’s Arizona Cooperative Fish and Wildlife Research Unit. They reported it in 2011 in the Wilson Journal of Ornithology (123:378–381).
The events began when an adult pair was found on 14 April at a nest site on the Davis-Monthan Air Force Base during a study of Burrowing Owls in the Tucson area. A male was at the burrow entrance, and an infrared video probe showed a female down in the burrow, apparently incubating. Both adults were banded on 27 April.
Another video probe detected one juvenile down in the burrow on 21 May, but on an unknown date in May the female abandoned the nestling and was not seen in the area again.
Jump to 12 July. That same female, identified by her bands, was discovered nesting in a pasture in southern Saskatchewan. This time she fared better, with a brood of seven.
Conway observed two other cases in the Tucson study area in which a female abandoned nestlings and renested with a new mate locally. The authors cited other second nestings in Arizona, California, Florida, and Mexico, but these were either in the same burrow or at new sites short distances away. This is the first time a Burrowing Owl’s second nesting in one season has been documented after a long-distance dispersal.
Such extreme behavior doesn’t make much sense when we typically suppose (sometimes too confidently) that creatures tend to expend the least possible energy for the best possible reward. But, of course, it’s even more unlikely that the owl managed to hitch a ride northward, Woody Guthrie-style, and happened to end up at another Burrowing Owl colony more than a thousand miles away.
This bird’s journey adds a welcome bit of awe to ornithology, doesn’t it?