Cetacean Society International

Whales Alive!

Vol. VIII No. 4 October 1999


Status Review Of Gray Whales

By William Rossiter, CSI President


On 25 August NMFS released their Status Review of the Eastern North Pacific stock of gray whales. The status review and associated workshop concluded the five year assessment of this population following its removal from the List of Endangered and Threatened Wildlife and Plants on 16 June 1994. The NMFS Office of Protected Resources will publish a Federal Register notice to announce the availability of this document and invite public comment. Please let us know if you would like to comment. Our web site may post the details.

Based on the 2.5% annual growth of this population to a present estimate of 26,600 individuals, and the lack of evidence of any imminent threats or danger of extinction to the stock, the Review recommended the continuation of this stock's classification as non-threatened. The Western North Pacific (Korean) gray whale stock should continue to be listed as endangered. Both recommendations were expected. However, notably without enthusiasm, the Review also concluded "that abundance monitoring should continue at some level, especially as this stock approaches its carrying capacity, and that, ideally, research should continue on human impacts to critical habitats." This official language translates to mean that continued funding for research is not a priority. Canada's Committee on the Status of Endangered Wildlife in Canada also lists the "Northeast Pacific population" of gray whale in the lowest category, "not at risk".

CSI and many other organizations are more concerned with the gray whales' situation than the Review allows the government to be, because of a series of recent events and pressures. Many criticize the NMFS review as playing down considerable evidence of problems. If the review had concluded with more caution it would not be suspect as just another victim of the Administration's policy of ensuring no impediments to Makah whaling.

Climatic warming effects on gray whales are unknown, but studies suggest depression of production in surface waters that may lead to reduced availability of gray whale prey in primary feeding areas offshore of Alaska. Gray whales rely on rich benthic amphipod populations in the Bering and Chukchi Seas to renew fat resources needed to sustain them during their winter migration to and from Baja California Sur. Gray whale feeding areas offshore of northern Alaska are characterized by low species diversity, high biomass, and the highest secondary production rates reported for any extensive benthic community. However, one study showed a 30% decline in abundance and biomass of the amphipods from 1986 to 1988, indicating that this resource is being stressed. There is some suggestion that the whales may be expanding the traditional summer range in search of alternative feeding grounds. Research is mandatory.

Toxic chemicals may put gray whales at risk from feeding in coastal waters. Research that these loads might depress immune systems or cause deaths were put off with the review's conclusion that prolonged fasting during migrations may alter the disposition of toxic chemicals within the whales' bodies. The higher concentrations of polychlorinated biphenyls (PCBs) found in stranded animals was said to be due to the retention of organochlorines in blubber during fasting rather than to increased exposure to these contaminants.

Oil spills were called non-threatening because, for example, one study reported gray whales swimming through surface oil from the Exxon Valdez oil spill (as if they had a choice). In another gray whales showed only partial avoidance to natural oil seeps off the California coast. Laboratory tests suggest that gray whale baleen, and possibly skin, may be resistant to damage by oil, but the review finally admitted that spilled oil or oil dispersant in a primary feeding area could negatively affect gray whales by contaminating benthic prey.

Human noise pollution was summarized as short-term behavioral responses to underwater noise associated with aircraft, ships, and seismic explorations. Some research indicates a 50% probability that gray whales will respond to continuous broad band noise when sound levels exceed about 120 dB, and to intermittent noise (e.g., seismic) when levels exceed about 170 dB, usually by changing their swimming course to avoid the source. In general the whales demonstrated a flexibility in swimming and calling behavior that may allow them to circumvent increased noise levels. However, the report also stated that ambient natural and man-made noise has a profound effect on the behavior of this coastal species, forcing them to modify their calls to optimize signal transmission and reception. One study described the significant decline in the number of whales using San Ignacio Lagoon during acoustic playback research in 1984, and the reoccupation of this lagoon the following winter, although at lower numbers than observed in 1978-82. The noise playback experiments documented alterations in vocal behavior and a significant decline in the number of whales occupying the lagoon during 24-hour periods of industrial noise simulations.

Salt extraction in San Ignacio Lagoon is still planned by Exportadora de Sal, or ESSA, within the buffer zone of the El Vizcaíno Biosphere Reserve. In 1995 the Mexican authorities denied the permit and initial Statement of Environmental Impact for the San Ignacio Lagoon expansion and established a Scientific Committee to define the problem. In August, a team from the United Nations Education, Scientific, and Cultural Organization (UNESCO) visited Mexico's Laguna San Ignacio World Heritage Site to determine whether the project may threaten gray whales, sea turtles, and other marine life. At a meeting on 23 August Mexican officials told the UNESCO team that plans for a salt-evaporation plant would not be approved if such a plant threatened gray whales that breed in the San Ignacio Lagoon. For current information on this major issue see http://www.nrdc.org.

Entanglements affected 47 gray whales from 1990 through 1998 along the U.S. West coast. 13 may have survived; the remaining 34 either died as a result of mortalities or were unknown. Under-reporting is a significant problem with entanglements.

Strandings along the U.S. west coast took 250 gray whales from 1990 to 1998. As of mid-June there were at least 84 gray whale strandings reported. The Review emphasized that 1999's high number was in part due to increased survey effort, and implied that they were not related. Of 89 stranded whales examined, 72% were adults, and 78% of those were females. From 1975 to 16 June 1999 there have been at least 518 strandings in Mexico.

Ship strikes took only seven known gray whales in the U.S. from 1990 to 1998. Many strikes are unreported if the whales do not strand or are not thoroughly necropsied.

"Aboriginal harvest" was the term NMFS chose, rather than the IWC's "aboriginal subsistence harvest", to comment on the 1998-2002 IWC quota allowing a harvest of 140 gray whales per year for local consumption by aborigines. Although disputed by many, NMFS parroted the formal U.S. position that the Makah Indian Tribe received a 5-year quota from the IWC in 1997 to harvest 20 gray whales for ceremonial and subsistence purposes. There is no credible evidence that subsistence is an issue with the Makah whaling. Although no gray whales have been allocated by the IWC to Alaskan Native subsistence hunters since 1991 two incidental takes of gray whales by an Alaskan Native were reported in 1995. From 1970 to 1998, an average of 139 gray whales were taken annually by Russia along the coasts of the Chukotka Peninsula. As part of a deal with the U.S. the Russian Federation has agreed to take no more than 135 whales annually from 1998 to 2002, leaving five for the Makah. According to the U.S. the Makah may harvest up to five gray whales per year from 1998 through 2002. A legal challenge to the Administration's actions is underway. There is no allowable commercial take of any gray whales, and the Convention on the International Trade in Endangered Species (CITES) regulates the transportation of animal parts. Both have been challenged by Makah statements vowing to trade with Sister Nations, even across national boundaries. Makah whalers struck and killed one gray whale on 17 May 1999. The Makah might whale again after 1 October, although no one knows outside Neah Bay. There are now two whaling canoes.


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