Owls Underground
The word Owl brings into mind a certain image, one of a silent intelligent hunter flying through the night ,roosting in trees and spinning it head like a pinwheel. The the owl family is a large group, 216 species strong, and whilst many are similar to that image in such a large family there are bound to be a few that go against the norm.
One of the most unique of these rebel owls is a small bird that can be found in the Americas which unlike the other members of its family can be found beneath the ground. Commonly known as the the Burrowing owl (Athene cunicularia) this species has developed the unusual behaviour of building their nest in burrows in the earth. There are many possible reasons for this strange behaviour, protection from predators is the most likely reason but there is also benefits of extra warmth since some of the areas they live in like deserts have nights where the temperature drops to freezing temperatures.
But although they live in these burrows they do not dig them themselves, the burrows used by this species are made by Prairie dogs (family; Cynomys), the burrowing owl will chose a burrow to its liking and force out its rightful owners. But surprisingly despite the need for empty Prairie dog burrows, the Burrowing owls do not prey upon these rodents often, possibly because alive they can go on to make more burrows that can be stolen, mostly their diet consists of invertebrates, small reptiles and small mammals like mice.
But this is not the only odd thing about this owl, it also has developed long legs which allow it to run and sprint after is prey as well as using traditional flight, and while most owls are nocturnal or crepuscular the Burrowing owl hunts during daylight hours. Another unusual hunting strategy the Burrowing owl employs is the laying of traps, they are known to collect feces from other animals in the area and pile them around around its burrow. This attracts dung beetles which is one of the invertebrates that makes up the owls diet. This beetle trap is clear proof that this bird is no bird brain another example of their intelligence is they’re method for deterring predators. This birds have recently been shown to be capable of mimicry, when threatened the burrowing owl will retreat into the safety of its burrow and makes loud rattling and hissing noises imitating a rattlesnake, a common predator in its environment.
Although this species is currently listed as least concern on the IUCN Red List of Threatened Species, unfortunately in recent years populations of the Burrowing owl have been in decline,
the reason for this is because of their relationship with the Prairie dog.
Human activities like farming have caused large numbers of Prairie dogs to be killed, some because they are seen as a pest and others because of pesticides and other poisons meant to protect crops. The fall in Prairie dog numbers means less burrows are being made for the Owls to exploit which has lead to this current decline.
The Burrowing owl is one of the most unusual birds known to man, if you enjoy learning about unusual and interesting check out my blog post on the Black Kites on Australia and their unusual hunting tactics .
Rowe, Matthew P.; Cross, Richard G.; Owings, Donald H. (2010). "Rattlesnake Rattles and Burrowing Owl Hisses: A Case of Acoustic Batesian Mimicry". Ehtology. 72 (1): 53–71
BirdLife International. 2016. Athene cunicularia. The IUCN Red List of Threatened Species 2016: e.T22689353A93227732. Downloaded on 01 February 2018