Research Technical Report

Humpback and Blue Whale Photographic Identification: Report on Research in 1996

Calambokidis, J., T. Chandler, K. Rasmussen, G.H. Steiger, L. Schlender, D. Ellifrit, and J.L. Quan (July 1997)

Cascadia Research Collective Technical Report, Prepared for Monterey Bay, Channel Islands, and Olympic Coast National Marine Sanctuaries, Southwest Fisheries Science Center, and University of California, Santa Cruz, July 1997. 40pp.

INTRODUCTION

This report summarizes research conducted by Cascadia Research and collaborators in 1996. This was part of a long-term research effort conducted by Cascadia Research with the support of a number of government agencies, principally Southwest Fisheries Science Center and the marine sanctuary program of NOAA. Intensive research of humpback and blue whales off California using photographic identification has been conducted each season since 1986 (Calambokidis et al. 1989a, 1989b, 1990a, 1990b, 1996, Calambokidis and Steiger 1995, Steiger et al. 1991). Major long-term objectives have been to:

• Determine the abundance of humpback and blue whales found in coastal waters of California, Oregon, and Washington.
• Determine if populations are increasing or decreasing and, if so, at what rate.
• Examine reproductive and mortality rates of both species.
• Examine movements, migratory destinations, and define the stock structure of the populations that use these waters.
• Examine other aspects of their biology including food habits and behavior.
• Evaluate the impact of human and environmental factors on these populations.

The focus of the 1996 research was to gather data to achieve these large overall objectives as well as to address several more regional or specific objectives. These included:

1. Target research effort in three National Marine Sanctuaries (Olympic Coast, Channel Islands, and Monterey Bay) to determine the number, distribution, and movement patterns of humpback and blue whales using waters in and around the Sanctuaries (conducted under Purchase Orders 43ABNC601919 for CINMS and 40ABNC601759 for OCNMS).
2. Examine the number and movements of blue, fin, and humpback whales off southern California during the Whale Habitat and Prey Study (WHAPS II) and off the west coast and offshore waters of the continental United States during the Oregon California Washington Line Transect Estimate (ORCA WALE) conducted by Southwest Fisheries Science Center (SWFSC). This research was conducted under Purchase Order 40JGNF601376.
3. Study the humpback and blue whales using the area around the Pioneer Seamount as part of the Marine Mammal Research Program designed to evaluate the potential impacts of the A TOC sound source (conducted under a subcontract from the University of California at Santa Cruz).

This report summarizes the research effort and methods used in 1996 and the preliminary findings from this research including the number of individual whales identified, resightings, and movements of some of these animals. While data obtained in 1996 will also be incorporated into the longer term objectives of the research effort, these overall findings will only be briefly reviewed here.