Loss of Habitat
Housing, farming, roads, and energy exploration have fragmented what once was vast areas of grassland prairie. These activities have eliminated some of the owls primary living space.
Loss of Burrows
Digging mammals like ground squirrels, prairie dogs and badgers are often seen as pests and are eradicated (by poisons). A reduction in these types of animals reduces the amount of available burrows for the owls for nesting.
If you've ever been lucky enough to see a Burrowing Owl in the wild in Manitoba you may have seen it hanging out on a fence post near a ditch or road side. They definitely enjoy perching on fence posts, hunting in ditches near road sides and even on the road and this leads to a higher frequency of owls being hit by vehicles.
In cool or wet seasons, prey shortages do occur and play a major role in productivity and survival of the young.
The use of pesticides can affect the owls directly and indirectly. Directly, the owls eat a lot of insects like grasshoppers, beetles, and crickets. Pesticides are used to kill off insects which leads to their being less available for the owls to eat. Indirectly, should an owl eat pesticide contaminated insects, the poison will bioaccumulate in the owls system and may ultimately cause death.
Burrowing owls have a variety of natural predators including badgers, foxes, and numerous avian species including larger owls and hawks.
Winter mortality is extremely difficult to measure in long-distant migrants that do not show a high fidelity to their nest site. Little is known about the migration path of Burrowing Owls from Manitoba to the Gulf of Mexico at present however high mortality is suspected for young in the first year.
There are several important knowledge gaps that still exist for the Burrowing Owl in Canada. The largest knowledge gap is linked to migration. Burrowing Owls migrate from Canada through the U.S. to the Gulf of Mexico. All owls are banded with alpha numeric, colour coded bands which are province specific. This allows for biologist and birders alike to identify owls along migration. Data on survival rates for both adults and juveniles during migration does not exist and migratory routes used and winter range for Canadian owls is limited. Observations of Alberta owls in both Texas and the Bahamas have been confirmed by Canadian wildlife biologists.
Presently, small (under 4 grams) GPS satellite trackers do not exist and until that time migration path and stop over points for Burrowing Owls during migration are hard to place. An increase in collaboration between Canada, the U.S. and Mexico conservation programs are needed to better understand challenges the owls face during the winter season.