Authors: N. Wilkins, R. Powell, A. Conkey, A. Snelgrove

The overall approach taken was to accumulate, summarize and evaluate the existing information on the species. This information is in the form of peer-reviewed scientific literature, published reports, expert opinion, unpublished manuscripts, archives of published and unpublished data, and a variety of public records. No new data was collected under this effort, and new analyses were not conducted beyond the basic and summary statistics required to gain a range-wide perspective on the central issues addressed in the status review. Where existing data were not adequate for reaching reliable conclusions, that fact is stated and the apparent gaps in information noted.

This report does not make any recommendations concerning the listing status of the species or changes in the listing status. This remains the responsibility of the USFWS.