Legal Action on the Pipeline

April General Meeting

Pee Wee Audubon

Thank You

Madrone Decals Available

Volunteers

PeeWee Reports

Midweek Walkabout Results

Birders Cruise the Bay

Developmental Center Open Space Trip

The Ethics of Intervention

Audubon Day at Bouverie May 17

Welcome New Members

Business Offers Membership in Audubon

Backyard Birding: Landscaping for Birds

Bad Day at Black Point

Saving the Marin-Sonoma Coast

The Ethics of Intervention

by Betty Burridge

Belief in the inherent value of life for each living thing is basic to our culture. Therefore, when environmentalists suggest that wildlife rescue groups should try to save members of native species but not non-natives, people who do not understand the ethic behind this point of view are likely to be shocked. They feel that every animal, native or not, has an equal right to live, and should be treated with the same respect and care.

I think we can define a "native species" as one which evolved with all the other organisms in the region where it is found. Especially vulnerable are the "specialist" natives, which eat specific foods, use specific nest materials, and are totally dependent upon the habitat in which they evolved. Within that habitat, a native, specialist species may be abundant, but it cannot adapt to the loss of the habitat or to excessive competition from interlopers.

A "non-native species," on the other hand, can be a domestic animal living at least part-time in the wild, or a wild species that evolved somewhere else and has been transported to a new habitat either deliberately or accidentally, usually by some act of man. Many of these birds are what is known as "generalists," adapted to live on a variety of resources. They are not picky about where they nest, what they eat, or whether the area they live in is subject to disturbance by man. In general, it is the non-natives that are thriving in large populations.

The difficulty lies in the fact that human activities have so disrupted the natural world, altering habitat and introducing non-native species, that we have placed many native species in jeopardy. It is not just the welfare of the individual about which wildlife rescue and conservation organizations are concerned, but the viability and welfare of the whole population of many native species.

In Sonoma County, we are fortunate to still have some specialist species. All of these are native species with small populations, and they are the ones we need to help. Saving one native warbler from a small population, for example, really can significantly strengthen the presence of that species. Saving one non-native European Starling, House (English) Sparrow, or Rock Dove (common pigeon), on the other hand, will not make a significant contribution to what are, in any case, thriving populations of those species.

Rescuing non-native generalists such as the numerous, competitive, and aggressive European Starling actually diminishes the survival prospects of native specialists such as warblers and others.

One of our native specialists that is directly affected by the European Starling is the Acorn Woodpecker. Formerly present in considerable abundance in habitats such as the Santa Rosa Junior College campus, the population of this noisy, gregarious and handsome woodpecker has suffered recent population declines, not only because of the removal of its 'special' oak trees, but also because of European Starling intruders taking over nest holes. Encouraging the European Starling makes no sense when considering the health of the Acorn Woodpecker population.

Another of our specialists that is under pressure is the Yellow Warbler. This tiny, bright yellow songster developed the ability to prosper in riparian willows and alders. Only a few other birds use the riparian habitat exclusively, and each of them further specializes, using different elements of the habitat from the others. The Yellow Warbler generally forages for food higher in the trees and bushes than the others, and conducts its life with other behavioral variations.

These subtle differences can vary by location, and sometimes even by individuals, and our understanding of them is incomplete. But the fact is, that the western Yellow Warbler can only exist in our scarce riparian habitat, and can brook no competition by any interlopers. Numbers of Yellow Warblers are declining every year.

Efforts spent in rescuing birds that compete with our native species also can absorb limited funds and volunteer energies, at the expense of the native birds.

Despite our best efforts, the extinction of native species continues at an alarming rate. In Sonoma County, we still have some portions of the original flora and fauna still intact. But if we want to maintain a diversity of species that includes the specialists native to our area, we must not encourage non-native species in the wild.

References: The Birders Handbook by Paul Ehrlich et al., Simon and Schuster publ. 1988. Sonoma County Breeding Bird Atlas edited by Betty Burridge, Madrone Audubon Society publ. 1995. Marin County Breeding Bird Atlas by David Schuford, Bushtit Books publ. 1993