Friday, July 1, 2011

Spotted Owls

Since the star of my blog- the saw-whet owl, is out of our project area for the summer, I will introduce you to another species- the Spotted Owl (Strix occidentalis). I was fortunate to have my first wildlife job in 1988 when I worked with the US Forest Service gathering baseline data on the Northern Spotted Owl (Strix occidentalis caurina- N. SPOW). Since, then the N. SPOW has been listed as threatened under the Endangered Species Act (1990) in Washington, Oregon and California, primarily due to loss of habitat (late successional forests), and in the last decade and second major threat - competition with the Barred Owl (Strix varia). The Barred Owl expanded its range from the east of the Rockies and is a larger, more aggressive and more opportunistic owl (in habitat and prey preferences) then the Spotted Owl. More on the Barred Owl later.

Working in Washington for a consulting firm for five years, I had the opportunity to help conduct a demographic study, where we located, captured, color-banded, and followed families of spotted owls and their young as seen in the photo above. These owls are amazingly tame and have incredible dark eyes. They are considered a large owl and primarily eat flying squirrels and wood rats.

The California Spotted Owl (Strix occidentalis occidentalis - CA SPOW) is found in our neck of the woods (the southern-most Cascade Range, Coast and Sierra Nevada Ranges) and is not currently listed (it is a CA species of special concern) although the Barred Owl populations are increasing here and becoming a threat to Spotted populations. I have worked with the CA SPOW for a several years for a consulting firm and currently for the US Forest Service. We are also monitoring their populaitons in the Sierra Nevada and documenting their reproductive success. To me, the subspecies are very similar in looks and behavior. The plumage of the CA SPOW is somewhat lighter than the N. SPOW which might you see in the picture below, a handsome male spotted owl - photo by my colleague Mary Muchowski. I do love my work!

No comments:

Post a Comment