Unsustainable Losses of Leatherbacks
After a run of a hundred million or so years, the Pacific leatherback turtle, Dermochelys coriacea, is looking death in the eye. Over the last couple of decades, exponential declines in numbers of nesting female leatherbacks have been reported from every beach where the animals were once known to be plentiful. The World Wide Fund for Nature reports that the number of adult female Pacific leatherbacks may be as small as 2,300, making it the world’s most endangered sea turtle.
For some populations that have suffered fantastic declines in recent years, the loss of even one nesting female may spell the difference between survival and extinction. So far this year, the longline fleet in Hawai’i is known to have killed at least one leatherback, whose fate was recorded by a federal observer. If statistical projections are to be believed (and not the notoriously unreliable logbooks of the fishers themselves), probably five leatherbacks have been caught, of which two or three have died.
Two years ago, the National Marine Fisheries Service determined in a biological opinion that the impact of the Hawai’i longline fleet on turtles (including leatherbacks) was so great, taking some 600 turtles a year, that it placed their recovery in jeopardy. Now that the swordfish fishery has been closed altogether, and tuna longlining is suspended annually in April and May in waters south of Hawai’i, NMFS has found that overall, the turtle take (some 81 animals) does not jeopardize their chance of recovery.
For the Western Pacific Regional Fishery Management Council, hostage to longline interests, this finding opens the door to lifting the limits on longline fishing in and around Hawaiian waters. If it can only determine where NMFS has drawn the line between jeopardy and no-jeopardy, it reasons, it can increase allowable fishing effort right up to the last turtle on the no-jeopardy side of threshold.
And so, as a first step in this direction, the council adopted a course of action that it expects to result in the lifting of the two-month ban on longline fishing in southern waters – a ban imposed precisely to protect the leatherback. Although leatherback turtles are not tempted by the bait on longline hooks (their diet seems to consist mainly of jellyfish and similar animals), the hooks can snare the turtles as they migrate across the Pacific.
Got Science?
Giving aid and comfort to the council was its Scientific and Statistical Committee. This group, which in May reviewed different scenarios for turtle takes prepared by the NMFS Honolulu laboratory, provided the council with a recommendation it simply could not refuse. Not only did it underestimate by half the number of turtle mortalities that might be expected to occur if the two-month southern area closure were lifted, it went on to conclude that “so few additional mortalities cannot be a rational basis for a fishery closure of such magnitude.”
The SSC prides itself on its scientific credentials. Yet its recommendation does not withstand scientific scrutiny. It is based on erroneous mortality figures and is unsupported by so much as a whiff of any analysis of the impact such additional losses will have on turtle populations, especially leatherbacks.
To be sure, the Hawai’i longline fleet catches only a small portion of turtles hooked by vessels fishing in the Pacific. Foreign longliners and driftnetters take many more turtles than the Hawai’i fleet. Yet this fact does not morally or legally absolve U.S.-based fisheries and those who manage them of the need to do everything possible to prevent additional turtle deaths.
The council complains that environmentalists are preventing the longliners and NMFS from developing fishing methods for swordfish that could hold the key to saving the turtles. Only by introducing mandatory gear changes for U.S. vessels targeting swordfish can the government force other nations to adopt turtle-friendly gear and techniques, this argument goes. And to develop such gear, it continues, modifications to longline gear (differently shaped hooks, different bait, different lines) and traditional setting techniques need to be tested at sea.
Environmentalists have objected, arguing that the so-called experimental fishing methods proposed by NMFS are but a gossamer veil hiding the driving motivation: resumption of commercial swordfish fishing, in the guise of a scientific experiment, that would end up killing almost as many turtles as the now-closed swordfish fishery used to take. The proposed permit for experimental fishing that NMFS is now seeking would allow the take of up to 499 turtles, or about 70 percent of the number caught annually in the swordfish fishery’s heyday. To save turtles, one must kill them, apparently.
The Hawai’i longline fleet may be suffering under the burden of regulations it was able to avoid for most of a decade – to the irreparable detriment of the turtles. A recent $5 million cushion from Congress should ease its pain. But the longliners continue to press for more. That they believe they have a right to take every last turtle this side of jeopardy, with the full support of a council held in its thrall, speaks volumes about the need for wholesale reform in the way the nation protects its ocean resources.
But beyond that, the plight of endangered sea turtles, and most especially leatherbacks, places on each consumer of seafood the need to act responsibly. Do not buy imported swordfish until foreign nations take measures to stop turtle bycatch. Do urge your elected officials to support international regulations to protect turtles. Cry out against any proposal to relax restrictions on the Hawai’i longline fleet.
After all, when it comes to leatherbacks, every turtle counts.
— Patricia Tummons
Volume 14, Number 1 July 2003
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