Friday, June 24, 2011

THE EASTERN PACIFIC GRAY WHALE: Another Imperiled Cetacean

By Taffy Lee Williams

Thanks to the tireless advocacy of the Palo Alto, CA-based California Gray Whale Coalition (CGWC) and its CEO Sue Arnold, the plight of the Eastern Pacific Gray Whale (EPGW) has received global attention. The CGWC recently filed a petition to relist the gray whale as depleted under the Marine Mammal Protection Act (MMPA) based on genetic studies conducted by a team of scientists at Stanford University. 


 
Gray Whale Calf, Courtesy Cetacean Society International, (Dorsey)


We used a genetic approach to estimate prewhaling abundance of gray whales and report DNA variability at 10 loci that is typical of a population of ≈ 76,000-118,000 individuals, approximately three to five times more numerous than today's average census size of 22,000.... These levels of genetic variation suggest the eastern population is at most at 28-56% of its historical abundance and should be considered depleted. (Alter, Rynes, and Palumbi. 2007. DNA evidence for historical population size and past ecological impacts of gray whales. Proceedings of the National Academy of Sciences)
Depleted status may be applied if a species falls below 60% of carrying capacity (for its environment); today’s estimate (18,000) is well within that range, according to the genetic analysis. In October, 2010, the California Gray Whale Coalition amassed the data and filed the petition with NMFS, hoping for the depleted “uplisting”, which would then compel a status review under the Marine Mammal Protection Act. NMFS appeared blatantly disinterested, at first allowing only a 14-day comment period (the protocol is 30 days!) and then failing to make relevant documents and a vital online submission site available to the public.  Despite generating almost 2000 supporting comments, NMFS declined, stating there was no evidence that the EPGW was below its maximum net productivity level, essentially ignoring the researchers’ DNA population findings. 

Many weren’t surprised at NMFS’ negative findings. CSI President Bill Rossiter points out that in recent years NMFS has supported almost all initiatives and policies which CSI and cetacean advocates consider exploitative. NMFS appears to be “driven by economics and politics far more than conservation.” (pers comm) While fighting to protect the gray, CGWC’s CEO Arnold surveyed coastal commercial fishing operations and whale watch groups and found broad contempt for NMFS for its mismanagement and failure to provide any measurable protection for marine resources. Finally, who could forget NMFS’ "winner take all" attitude toward the military with respect to sonar and destructive naval exercises coinciding with gray whale migration routes? In a show of submission and a toss-away of environmental laws, NMFS is adopting the Navy’s environmental impact statements for its own and unquestioningly approving training that will take 11 million marine mammals over 5 year period! 
Politically, the gray whale may simply be “in the way”. Besides impacting training ranges and naval exercises, a depleted listing would likely snuff out the Makah and Russian gray whale quota, numbers used as US “bargaining power” at contentious IWC meetings.  Meanwhile EPGW numbers continue to dwindle: 2009-2010 was the fourth consecutive year with low calf numbers, and emaciated grays are washing up dead. One necropsy found a gray had swallowed over 20 plastic bags, small towels, surgical gloves, duct tape, and other debris. Grays are a favorite target of orcas as well, and with global warming and overfishing robbing them of prey, gray whale plundering must cease, and a recovery plan immediately implemented. 
The 30 million-year old gray whale species evolved into three populations: the Atlantic Gray Whale (likely exterminated by early whaling), the Western Pacific Gray Whale, critically endangered with fewer than 100 individuals remaining, and the at-risk Eastern Pacific Gray Whale, still a darling of west coast whale-watching tours. New information on feeding and life cycles is presenting more urgent cause for heightened protection. Unlike most water-sifting baleen whales, grays are bottom-feeders, digging up sediments and straining sand to feed. Scientists have noted that as grays sift through the seabed, benthic amphipods are released and carried to the surface where they are consumed by sea birds. (Grebmeier & Harrison, Seabird feeding on benthic amphipods... Marine Ecology Progress Series, 1992.) 
Unique among whales, the gray bulldozes the oceans, digging troughs through the sea floor for food. In the process, they resuspend ocean sediments, bringing food to the surface. "A population of 96,000 gray whales would have resuspended 12 times more sediment each year than the biggest river in the Arctic, the Yukon," Alter said, "and would have played a critical role in the ecology of the Bering Sea." Other species may have felt the loss of whales as well. "The feeding plumes of gray whales are foraging grounds for Arctic seabirds," Palumbi said. "96,000 gray whales would have helped feed over a million seabirds a year." (Stanford News Service. http://news.stanford.edu/pr/2007/pr-whales-091207.html)
Iron and micronutrient-rich whale waste feeds phytoplankton blooms which in turn regenerate the marine food web in a whale-dependent cycle. Phytoplankton also absorb vast quantities of CO2 as they bloom; scientists are hopeful that the whales’ life cycle may actually help gain some greenhouse gas relief. Removing whales increases seawater anemia; the more whales that are in the ocean, the healthier the waters and the complex marine ecosystem will be.
The Stanford team disputes claims that the starvation the grays are exhibiting is because their population has exceeded carrying capacity. But if the genetic variability show 96,000 as the once-viable population, it is the Arctic feeding grounds that have been compromised - by overfishing and global climate change.
Previously it was assumed that the thin and starving animals are a consequence of the gray whale population exceeding its historical ecological limits. But if the Pacific normally housed 96,000 gray whales, then starving whales may be suffering reduced food supply from changing climate conditions in their Arctic feeding grounds. This possibility parallels reports last year of major climate shifts in the Arctic ecosystems in which gray whales feed. The study also suggests that lowered numbers of gray whales no longer play their normal role in ocean ecology. (Ibid.)
The fight to protect the gray is not over. NMFS has failed to adequately respond to public comments generated by CGRC’s petition.  Legal options are on table, and the grays have advocates all over the world who are deeply committed to their preservation. Follow all the latest news at www.californiagraywhalecoalition.org, and the NEWSFEED at ny4whales.org.

For more info on the California Gray Whale, and for ways you can help, visit the 

Sign the Gray Whale Petition to US Congress:


Threats to the Eastern Pacific Gray Whale from NOAA MAPS

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