Abundance of Pacific harbor seals (Phoca vitulina richardsi) in Oregon: 1977-1996

Identification Information

Citation

Originator: Brown, R. F.

Publish Date: June 1997

Online Link: None

BPA Project #:

Contact Information

Agency: Oregon Department of Fish and Wildlife

Name: Cedric Cooney

Job Position: Natural Resources Data and Systems Manager

Telephone: 503-947-6094

E-Mail Address: Cedric.X.Cooney@odfw.oregon.gov

Description

Abstract: Aerial photographic surveys of harbor seals (Phoca vitulina richardsi) were conducted along the Oregon coast from 1977-1996. These abundance trend surveys were conducted during the spring and early summer reproductive period (May-June). Statewide counts of seals ranged from 2,224 adults and juveniles in 1977 to 5,322 in 1996. A maximum count of 5,610 occurred in 1992. By applying a correction factor to counts of all animals (including pups) it was estimated that just under 10,000 harbor seals occurred along the Oregon coast in May 1996. Over the entire survey period harbor seal numbers increased at an average annual rate of 4.5%. During the years 1982-1992, seal counts increased at a rate of 5.0% per year, while counts from 1988 to 1996 increased at only 0.3% per year. The recent slowing in the rate of growth suggests that harbor seals in Oregon may be approaching an abundance level that is in balance with the supporting coastal environment. However, several more years of surveys should be conducted to confirm the status of this species in Oregon.

Purpose:

Time Period of Content: 1977-1996

Geographic Extent: Oregon

Status: Final

Use Constraints:

Format: PDF file

Data Quality Information

Lineage-Source:

Data Information

No data information was supplied.

Entity and Attribute Information

Attributes Description: Not yet described

Bibliography Information

Field Name	Value
Biblio ID	5865
Year	1997
Publisher
Request Type	Technical Report
Location	Salem HQ
Date Created	Jun 1997
Date Cataloged	4/5/2001 22:27:51
Date Published	1997
Type	yellow cover
Pages	12+
Volume
Status	2
Descriptor	Pacific harbor seals; OREGON
Date Entered	2005-08-03 00:00:00
Location In Clackamas Library	Wildlife section; Marine Mammals
Author	Robin F Brown
Duplicates	0
Number Remaining After Requests
Presumed All Distributed
Back Room Duplicates
Author	Brown, R.F.
Risk
Species
Disposition Of Requests	State Archive: Request filled
Disposition Of Requests	StreamNet Library: Requested, but no copies available

Is a physical copy maintained for reference at Headquarters? Yes