WASHINGTON (CN) – Only five distinct population segments of loggerhead turtles will be listed as endangered, under the Endangered Species Act.
This is a step backward from the seven distinct population segments (DPS) the U.S. Fish and Wildlife Service and the National Marine Fisheries Service proposed to list in March 2010.
In their proposed listing, the agencies had said that the North Pacific Ocean, the South Pacific Ocean, the North Indian Ocean, the Southeast Indo-Pacific Ocean, the Northwest Atlantic Ocean, the Northeast Atlantic Ocean and the Mediterranean Sea DPS should be protected under the act.
The agencies say they collected new evidence showing that the numbers of turtles in the Northwest Atlantic and the Southeast-Indo Pacific DPS were greater than had previously been thought, and that the number of breeding pairs had not declined as had previously been thought.
The Center for Biological Diversity said that listing the North Pacific loggerheads meant “significant threats, such as longline and gillnet fisheries, will be subject to increased scrutiny, and may need restrictions to reduce their deadly impacts.”
Dr. Chris Pincetich, a marine biologist with the Sea Turtle Restoration Project said that, “the failure to recognize that Northwest Atlantic loggerheads are endangered ignores the massive impacts of the BP oil spill and increasing threats from shrimp-trawl fisheries on this imperiled population.”
The agencies will propose critical habitat for both the endangered North Pacific and threatened Northwest Atlantic DPS.
The designations effectively ban all trade and import of loggerhead turtle products, and commit the United States to continue to seek international bans on the take of turtle.
Internationally, fishing – both net and long-line – is the number one threat to loggerheads, despite provisions in most world fishing conventions to protect the species.
Loggerhead hatchlings have a 40 percent survival rate overall, but individual populations have suffered drastic declines in hatchling viability due to habitat destruction and deliberate hunting of nesting females.
Climate change has a significant impact on the loggerhead’s reproductive success, also, as the temperature of the sand around the nest determines the sex of the hatchlings, with higher temperatures favoring females and lower temperatures favoring males.
Because females have up to a 25 year span for reproduction, and can live to be over 50 years old, long term trends in the population can be predicted based on the survival rates and sexual population biases measured in a single female’s successive broods.