Breeding Survey and Data

Whidbey Audubon Society and the Island County Marine Resources Committee sponsor our on-going study of breeding Pigeon Guillemots on Whidbey Island, Washington. We also receive funding from Ott and Murphy Winery and the National Audubon Society. The research project assesses the population and productivity of the approximately 1,000 guillemots that form breeding colonies around the island.

Whidbey Island, a long snake-like island in north Puget Sound, stretches from about 30 miles north of Seattle nearly to Canadian waters. Tall bluffs, particularly along the island’s west side, offer safe burrow sites that are relatively near rich feeding areas. In all but two of the 25 regularly surveyed colonies, the guillemots burrow into nearly vertical sandy cliffs termed “erosional bluff.” (One colony breeds on a deserted offshore wooden structure; the other in rocky cliffs at the far northern end of the island.)

delivery to burrow-new-During each breeding season over 40 trained volunteers visit assigned colonies once each week from late June through the end of August. The volunteers sit quietly and monitor the birds for one hour. They take population counts, locate nesting burrows, record the birds’ behavior, document adults visiting and carrying food to the burrows and record disturbances.

The summer study also includes more concentrated observation by a paid intern/contractor. The contractor spends five hours per day visiting a single colony and, beginning at dawn, records all behavior of the birds.

The project will continue for several years in order to track the Pigeon Guillemot population, gauge the rate of reproduction and determine their feeding needs. Since this species is near the top of the food chain, its vitality is a good indication of the overall health of Island County’s Marine Stewardship Areas, which include the waters around Whidbey Island.  Summary graphs can be viewed on our data website:

http://www.pigeonguillemotdata.org/

 

 

 

 

Comments are closed.