Project Description

As in 2007, field work will be conducted by CAEP in the summer of 2008 as part of a multi-disciplinary study of North Pacific right whale ecology. The cruise will work in the Bering Sea to satellite tag and gather photo-identification, genetic, and oceanographic data on right whales. Given the scarcity of this species, however, time will be available for work on other large whales, thus maximizing the use of the vessel time and minimizing other operating costs. Dedicated effort aimed at gathering photo-identification data, biopsy samples, and associated information will be focused on (in order of priority after right whales): 1) humpback whales, 2) blue, fin and sei whales, if found. These data and samples will be provided to collaborators to investigate population characteristics and migratory connections between the study areas and other regions (e.g. the U.S. west coast and Mexico).

Analytical support will also be provided towards completion of the SPLASH project on humpback whales in preparation for publications and a possible status review. A pilot project involving satellite tagging humpback whales on Silver Bank in the West Indies will assess habitat use relative to a new cooperative 'sister-sanctuary' agreement between the Dominican Republic and NOAA. Finally, work will be conducted with former Soviet biologists to assess the true catch record of North Pacific whale species relative to the illegal whaling conducted by the USSR.

Issues & Justification

Humpback whales

North Pacific humpback whale populations were thought to have been reduced from about 15,000 prior to commercial exploitation to just over 1,000 after whaling and remain listed as endangered today. Data from photo-identification and genetics studies have provided some information on stock structure, verifying a high degree of site fidelity to feeding areas and some intermixing in the wintering areas. However, only limited data exist on the numbers, sizes, and potential boundaries of most feeding areas in the North Pacific.

While estimates of abundance and rates of population growth of NP humpback whales were conducted in the 1990s, their use today is limited by several factors including their age and potential biases due to sample coverage. In addition, no genetic samples were collected, and health and human impacts were not assessed.

Understanding the structure of humpback whale feeding areas and abundances in specific areas is critical for management and for an assessment of the affects of human interactions. Humpback whales have only been well studied in a few areas of the North Pacific The number of feeding areas and the boundaries of many areas in the North Pacific are unknown. Assessing impacts of incidental serious injury and mortality from commercial fisheries has not been possible due to the lack of information on the boundaries and abundance of animals in these feeding areas.

The SPLASH project is already providing information to address these issues, preparatory to a possible ESA status review of NP humpback whale populations. Primary field work for the project ended in the winter of 2005/6, and priority was subsequently given to analysis of the large quantity of photographs and samples collected. Analytical support will be provided for this effort. Additional field work by NMML and collaborators in the Gulf of Alaska and Bering Sea will provide supplementary data to assist in the status review.

Other species and issues

Blue whales were extensively exploited in the North Pacific in the 20th century. Today, the population off California is quite well studied, and estimates of abundance indicate a healthy population which is recovering. Far less is known about blue whales elsewhere in the eastern North Pacific. Acoustic detections using the U.S. Navy's SOSUS system commonly find blue whales in the Gulf of Alaska; however, the sighting of blue whales by a SWFSC cruise south of Prince William Sound in 2004 represented a comparatively rare event. Whether these visual and acoustic records indicate a population expanding to recolonize its historical range is not clear, and the lack of basic distribution and demographic information has hindered the development of recovery strategies.

Although right and humpback whales are currently the main priority for work by CAEP, we intend to use research cruises aimed primarily at these species to gather information, photographs, and biopsy samples of blue whales if any are found.

Similarly, we will, as practical, collect biopsy samples of fin and sei whales during such cruises to initiate preliminary assessment studies of these species in the eastern North Pacific.

All research will be broadly collaborative in nature.

Humpback whales utilize Silver Bank off the Dominican Republic as the largest breeding ground in the North Atlantic. The area is a sanctuary (created in 1986), and has recently been involved in a 'sister sanctuary' agreement with the Stellwagen Bank National Marine Sanctuary off Massachusetts. A collaborative pilot project will be conducted in January 2008 to attach satellite tags to a small number of humpback whales on Silver Bank in order to assess their habitat use relative to developing a management plan for this species in Dominican waters.

Additional analytical work will be conducted with former Soviet biologists to assess the true catch record of North Pacific whale species relative to the illegal whaling conducted by the USSR. Catches of many species by the USSR were greatly unreported in the Southern Ocean and North Pacific, and correction of this record is essential to an assessment of current population status relative to historic (pre-exploitation) population size.

Goals

• Humpback whales

The overall goals of the SPLASH project are as follows:
• Obtain a current estimate of overall abundance for the North Pacific including estimates for specific wintering and feeding areas and whether they are increasing or decreasing.
• Identify the population structure of humpback whales and how these influence genetic diversity and exchange.
• Determine key population parameters including reproductive and mortality rates as well as age/sex structure and pregnancy rates.
• Identify habitat and characterize use especially for areas used by humpback whales that have been well studied.
• Specific goals for this project are:
• Provide analytical support for SPLASH data and samples to elucidate population structure and other issues for North Pacific humpback whales prior to an ESA status review.
• Collect additional photo-identifications and biopsy samples from the Gulf of Alaska and Bering Sea region to supplement the SPLASH data set.
• Other whales/issues
• Collect photo-identifications and/or biopsy samples of other large whales (with an emphasis on blue whales) in the Gulf of Alaska and Bering Sea regions to initiate collaborative investigations of population characteristics and rates of exchange with other areas of the North Pacific.
• Satellite tag up to five humpback whales on Silver Bank to assess habitat use within the region.
• Work with former Soviet biologists to correct the catch record for large whales to improve current population assessments.

Methods

A one-month research cruise will be conducted by CAEP staff in the summer of 2008 to study right whales, but this cruise will also dedicate effort to photo-identification and biopsy sampling of other large whales. The cruise will leave from Dutch Harbor, and survey areas of the Aleutian Islands and Bering Sea. When not working with right whales, humpback and blue whales will be approached for photo-identification and biopsy sampling using small boats deployed from the main research vessel. Similarly, though with lower priority, fin and sei whales will be sampled as practicable.

Humpback whale photos and samples will be integrated into the SPLASH collections and archived to assist in ongoing analyses. Blue whale photos and samples will be provided to Cascadia Research to permit investigations of the migratory connections between these animals and whales sampled off California, Oregon and Washington. Fin and sei whale samples will be held at NMML and collaborations with other researchers will be established as appropriate.

Satellite tags will be applied to up to five humpback whales on Silver Bank in January 2008, using donated time on a commercial dive boat. The work will be conducted with Dominican scientists, in collaboration with the Ministry of Environment and Natural Resources. Whales will be tracked by ARGOS satellite.

Correction of the Soviet whaling catch record will be accomplished through discussions in Russia with former Soviet biologists.