Pollution and lack of food is killing orcas
24th August 2000
By HOWARD GARRETT
The recent decline in the population of the Southern resident orca community is real, but we are not killing the whales by watching them, as suggested in an Aug. 10 opinion piece.
The best available scientific consensus suggests that it is the decline of salmon and toxic pollution and the ripple effects of the captures 30 years ago that are combining to negatively impact the whales. Added stress due to boat interactions is a factor, currently being researched by shore observations conducted by Orca Conservancy and others, but to date the results of this and other studies of boat/whale interactions are mixed.
An April 1 meeting of orca researchers at the National Marine Fisheries Service in Seattle generally agreed that the lack of salmon, compounded by PCB contamination, are the primary causes of the 17 percent decline in the Southern residents from 1995 through 1999. When the whales are hungry, the toxins that have accumulated in their blubber are released into the blood where they can disrupt endocrine systems, leading to immune deficiencies and reproductive problems among other potential impacts.
In addition, the removal by capture of most of the Southern residents born between about 1961 and 1971 has taken a 10-year age cohort of females almost entirely out of the community. Those females would now be in their reproductive years, and their absence has contributed to the scarcity of newborns in recent years. Of special concern is the failure of the five females born in the 1960s who avoided capture to reproduce successfully since 1986, possibly due in part to the gradual buildup of toxic contamination in their bodies. This is yet another reason why Lolita, aka Tokitae, now held captive in Miami, should be returned to her habitat and family, to add herself and possibly a calf or two to the community.
The situation may not be quite as alarming as some would indicate. Salmon populations appear to be rebuilding, at least temporarily, due to regional cooling of ocean temperatures in the Pacific Northwest, which is expected to continue for the next few years. Since early 1993, approximately 24 orcas are known to have been born into the Southern resident community. Of those, 19 are still alive and appear to be healthy.
Over the past few years, whale watching companies have by and large learned to behave responsibly around orcas, as has most of the public. Efforts to publicize voluntary boaters' guidelines, now being done by the Soundwatch program, whale watch operators and many others, have already alleviated much of the impact of boat traffic. Increased coverage of boaters and continuing publicity throughout the region about the need to avoid stressing the whales could remove most of the remaining problem.
Whale-watching can help people to personally experience the grace and mystery of orcas. People often grow to care about the whales from seeing how they live. The problem the orcas face is the same one we all face, systemic neglect of our watershed and marine habitat. Though restoring salmon habitat is more complex than regulating boat traffic and calls for more creative solutions, only healthy, abundant runs of salmon will provide the sustenance the whales need if they are to survive and continue to inhabit the inland waterways of Washington.
Howard Garrett is president of the Orca Conservancy in Greenbank