Project Description

In 2004, CAEP initiated a North Pacific right whale tagging project. This is a collaborative study with the whale tagging group at the Greenland Institute for Natural Resources (GINR) in Copenhagen (Dr Mads Peter Heide-Jorgensen). The proposed study in FY08 is directed at the North Aleutian Basin (NAB) Lease Sale area but also at other known habitats for right whales in the Bering Sea. The project, which is funded by Minerals Management Service (MMS) and the North Pacific Research Board (NPRB) will combine satellite tagging and other methods in a multidisciplinary approach to the study of right whale ecology in the Bering Sea, and will follow a limited field season in 2007. The 2008 study will use satellite-monitored radio tags together with vessel surveys, acoustic detection technology, genetic analysis, photo-identification and oceanographic sampling and concurrent aerial surveys. Principal aims are to investigate the distribution, movements, diet, habitat use, population structure and migration of right whales in the study area. After tags are deployed, the tracks of tagged whales will be used to locate right whale habitats and aggregations, and from this to conduct biopsy sampling and photo-identification as well as directed oceanographic studies. If tags are deployed late enough in the season, and/or remain attached for long periods, long-range movements and migratory destinations may be assessed.

Continuation of photo-identification and genetic studies will allow a better understanding of the number of individuals, reproductive histories of mature females, the genetic structure and diversity of the population, and the sex ratio. Paternity analysis of mother/calf pairs may also provide insights into the existence of unsampled males in the population.

Issues & Justification

The North Pacific right whale, Eubalaena japonica, is one of the most endangered of all large whales. Whaling for this species began in the Gulf of Alaska 'Northwest Ground' in 1835. By 1849, right whales were depleted in the eastern North Pacific and were scarce throughout their range by 1900.

Right whales were protected worldwide in 1935 through a League of Nations agreement. A small number continued to be killed by Japan and the USSR for scientific research. The USSR also illegally caught many right whales in North Pacific. In the eastern North Pacific, 372 right whales were killed between 1963 and 1967; of these, 251 were taken in the Gulf of Alaska south of Kodiak, and 121 in the southeastern Bering Sea. These takes devastated a population that, while undoubtedly small, may have been undergoing a slow recovery.

Since an initial detection of right whales in 1996, NOAA surveys have found right whales in the same general vicinity of the southeastern Bering Sea in all years from 1997 to 2002, as well as in 2004. The size of the population, while unknown, is clearly small, and its reproductive viability remains uncertain despite observations of possibly as many as three mother/calf pairs in the summer of 2004. Nothing is currently known of the incidence of anthropogenic (e.g. entanglement and ship-strike) or other problems that may be further hindering the population's recovery. The impact on right whales and other listed species of proposed oil and gas development in the North Aleutian Basin is of concern; this includes problems which may be associated with seismic surveys conducted during the early stage of this development. Consequently, funding from MMS has been made available to conduct research on right whales in this region. Separate funding specifically for additional satellite tagging in FY08 has come from NPRB.

Given its precarious status, the eastern North Pacific right whale must rank among the highest priorities for marine mammal conservation by NOAA Fisheries. The lack of basic information on its distribution, biology, and behavior, as well as about existing threats, is a major impediment to the formulation of recovery strategies. Furthermore, as a result of a court order in 2005, NMFS designated Critical Habitat for this population; further information is urgently needed to refine our understanding of right whales and their ecological needs, notably relative to oil and gas development.

Accordingly, acquisition of the data described above is one of the highest priorities for CAEP and NMML. A multi-disciplinary approach provides the best economy of research funds and integrates a suite of methodologies into a focused study of the ecology of this critically endangered species.

The first year of the MMS-funded project involved a vessel-based survey in August, 2007, but no right whales were found. This was likely to due to 2007 being a so-called 'cold-pool year' in the Bering Sea, which caused a major shift in plankton distribution; as a result, right whales were not found in the habitat in which they had been seen in the previous few years. Use of extensive aerial surveys, and a predicted return to pre-2007 environmental conditions, is expected to greatly increase the chance of finding right whales in 2008.

Goals

• Deploy up to 5 satellite tags on North Pacific right whales.
• Use the movements of tagged whales in combination with vessel-based acoustic detections to locate concentrations of right whales.
• Assess the distribution and occurrence of right whales in the lease sale area and adjacent regions.
• Conduct photo-identification and biopsy sampling on all observed whales to continue studies of the genetic and demographic characteristics of the population.
• Assess the frequency of fishing gear entanglement using photographs of scars on the caudal peduncle and elsewhere.
• Conduct oceanographic sampling to characterize the habitat used by right whales, including abundance and spatial distribution of their prey.
• Determine the movements of right whales within and between feeding areas in the Bering Sea and Gulf of Alaska.
• Determine migratory routes and location of wintering areas.

Methods

Shipboard and aerial surveys will be conducted in the summer of 2008. Satellite tags will be deployed during this time. Tagged animals will be tracked, and right whales will be detected visually and acoustically in a survey of known habitats as well as of areas entered by the tagged animals. Nine scientists will participate in the shipboard survey, including photographers (for photo-identification of individual whales), biopsy samplers, acoustic technicians, and an oceanographer/marine ecologist. If weather permits, small boats will be launched from the research vessel to closely approach right whales for the purpose of tagging, photography, and biopsy sampling. A multi-disciplinary study of feeding ecology will be initiated in 2008, combining acoustic tagging with extensive oceanographic sampling.

An existing Argos-based satellite tag design used successfully on bowhead and humpback whales has been modified to be used on North Pacific right whales. The tag is implantable using an 8-m pole, and is designed not to penetrate past the blubber layer of the whale. Tags will be configured to transmit every day for an initial period, and then only every second or third day to maximize battery life and therefore tracking potential.

Entanglement risk will be assessed by examining the frequency of entrapment-related scars on the caudal peduncle and other body parts of right whales.