How much interference is too much for the Okanagan owls?

Bob Handfield, past-president of the South Okanagan Naturalists' Club explores the issues owls are facing.

Over geologic time many species have gone extinct and new ones have evolved.

That is the way nature works. Right now, however, many species are in serious trouble and close to going extinct because of man’s activities. While some people argue that man is part of nature and therefore any species that we cause to go extinct is just a result of nature at work, most people take a different view and argue we should do what we can to minimize our impact on other species. Many go further and argue that we should not only minimize our impact but rather we should actively try to undo the harm that has already taken place.

One local example of such a project is the program to re-establish burrowing owls in the Southern Interior.  Burrowing owls used to be common in the grasslands of the Okanagan Valley and the Merritt and Kamloops area.  As a result of human disruption of their habitat, the owls declined in numbers over the years and became extinct in B.C. by 1980. A program to re-establish them in the South Okanagan was undertaken during the 1980s by capturing owls in the U.S. and bringing them to the Okanagan.  Despite the significant effort and money put into this project, a breeding population was never established.

More recently, a new program to reintroduce burrowing owls in B.C. began, first in the grasslands between Kamloops and Merritt and now also in the South Okanagan. Unlike the first attempt, this program breeds captive owls and then releases those into the environment rather than “importing” foreign owls.  While it is still too early to declare this program a complete success, some owls have returned after migrating south for the winters, so it seems to be working.

A much more controversial program to undo a past wrong has been proposed in the U.S. in an attempt to save the spotted owl from extinction.  Much has been written about spotted owls over the past 30 years or so and their need for mature old-growth forests. But, of course, old-growth forests are in big demand by timber companies  so spotted owls have been in significant decline over their entire western range.  It is estimated there are only about 10 spotted owls remaining in B.C. although it is thought there is sufficient old growth habitat to support perhaps 25 to 30 pairs.

Compounding the problem for spotted owls is increasing competition from barred owls, an eastern species that has been spreading west and increasing in number as forest cover has changed.  Barred owls, while closely related to spotted owls, are more aggressive and do not require the same degree of old growth forest habitat. Studies have shown that when barred owls move into an area, Spotted Owls decline or disappear altogether.  Conversely, if barred owls are removed from an area of suitable habitat, spotted owls make a comeback.  It is this latter fact that leads to the controversy — an experimental program has been proposed to cull barred owls in areas where spotted owls have been known to be present in the recent past.

So it seems we have come to the point where we are culling one native species to save another (more) endangered native species. While some think this is an acceptable short-term solution to save spotted owls, others think we are going too far. It seems that no matter what humans do, one species or another suffers.

Part of the problem with both of these programs is that they focus on individual species rather than ecosystems.  Burrowing owls declined, in part, because we disrupted their ecosystems – they depended on the burrows made by badgers and prairie dogs but our agricultural and development practices disrupted those communities.  If we are to save the natural world from extinction we have to save ecosystems, not individual species.

Wild at Heart

In celebration of its 50th anniversary, The South Okanagan Naturalists’ Club and The Nature Conservancy of Canada (also celebrating its 50th anniversary) are joining with the Penticton Museum in presenting the exhibit Wild at Heart, on until Aug. 31. Learn more about the South Okanagan Naturalists’ Club at www.southokanagannature.com.

Bob Handfield is the past-president of the South Okanagan Naturalists’ Club.