Saving the Burrowing
Owl
Owl You Need to Know
Hoo are they?
The
Burrowing Owl (Athene cunicularia
hypugaea) is a very unique owl species. Unlike other species, the burrowing
is especially petite in size measuring up at an average 20 cm from head to feet
(Environment
Canada, 2010). This size is generally the same for both male and female owls.
They are also a primarily ground dwelling animal which works perfect for their
long legs when they sprinting across open prairies. The physical
characteristics of their feathers also reflect their surroundings. You can see
burrowing owls sporting brown heads and wings with white spotting. Their
prominent white eyebrows make it seem as they are regularly in a grumpy mood. Their
diet can consist of anything from small rodents, insects, and lizards to frogs,
toads, and birds (Environment Canada, 2010). Yum!
Where the hoot do they
live?
To date, the
burrowing owl can be found in Canada and the Western part of North America
extending as far down as Mexico and into South America as a result of
deforestation (Environment Canada, 2010). As mentioned
before, these owls inhabit areas of short grazed prairies. As you might have
guessed, they burrow! Even though they are capable of digging their own burrows,
they most often occupy the burrows previously made by other animals such as ground
squirrels or prairie dogs. The burrow serves as an excellent protection from
local predators. When a potential intruder approaches, the owl retreats into the
burrow and makes a noise similar to that of a rattlesnake in order to scare
predators away. Genius!
What the hoot is
happening to the population?
Unfortunately,
the burrowing owl was listed as Endangered under the Alberta Wildlife Act in
June of 2006 (Environment Canada, 2010). This is a result of a
decline of the population over the previous 10 years. There has been a total of
a 50% decline in parings of owls including 40% of that decrease occurring over
the previous 5 years (Environment Canada, 2010). Although the
burrowing owl is only currently listed as Endangered in Canada, these
population declines affect the birds in North America because they are
migratory animals. Uh Oh!
Hoo is threating their
existence?
The elements that
contribute to the decline of burrowing owl population are related to habitat loss
and modification, mortality of mature birds on the breeding grounds, low
productivity, and mortality on migration or wintering grounds, as well as human
disturbance and industrial development (Environment Canada 2009). Yikes!
Habitat & Industrial
Development
Burrowing
owls thrive in habits composed of grazed grasslands because it positively
contributes to its nesting and foraging activities (Wedgewood
1978, Hjertaas et al. 1995, Clayton 1997).When farmers introduce tall
vegetation, it reduces prey species availability which in turn declines the owl
population. The tall vegetarian also interrupts the actions of the animals that
create the burrows that owl utilize for
nesting. Burrowing owls have accommodated for the increase in road networks
across their burrowing habit by nesting in roadside ditches. Although the owl
has long legs for running, they are no match for the speed of a car. In turn,
cars collisions have raised mortality rates (K De Smet pers. Comm).
Predation
Various Mammalia and avian species have been
a large contribution to burrowing owl mortality (ASRD and ACA 2005; Environment
Canada, 2010). For example, badgers have been the major cause of adult
mortality in burrowing owl female thus removing the primary caregiver to
further generations. It is also thought that the rise in hawk populations due
to fences, utility poles, hedgerows, trees, and artificial nests have increased
predation on owls.
Pesticides
The indirect effects of pesticides are seen
when owls consume poisonous rodents and insets. The biggest enemy insecticide
is Carbofuran. This insecticide increases mortality and lowers reproductive
performance (James and Fox 1987).
What the hoot is being
done to help?
Alberta, Canada
has created a Burrowing Owl Recovery Plan in the hopes of bringing the
burrowing owl population back to sustainable numbers. The main goals are to
maintain and restore habitat suitability and quality. The strategies are:
ü Management
of burrowing owl habitat
ü Optimize
survival of burrowing owls
ü Public
education and awareness
ü Population
monitoring
ü Research
ü Identification
of available resources
Pictures in order of appearance:
**Information obtained from Alberta Burrowing Owl Recovery Plan 2010-2017 unless otherwise
cited**
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