Humanity may forfeit the chance to save North Atlantic right whales from extinction if new international conservation policies are not drawn up and implemented quickly, according to a new Cornell study in the June 2018 issue of Oceanography.
Following a dramatic northward shift in the whales’ territory, scientists last summer confirmed the deaths of at least 17 right whales primarily in Canada’s Gulf of St. Lawrence. This range shift brought right whales into areas unprotected by policies meant to reduce ship strikes and fishing gear entanglements.
“The 2017 Gulf of St. Lawrence emergency management action was informed by the temporary, near real-time right whale search effort, but these rapid-response measures were arduous and expensive,” said Erin L. Meyer-Gutbrod, Ph.D. ’16, now a postdoctoral scholar at the University of California, Santa Barbara, who co-authored the study with Charles Greene, Cornell professor of earth and atmospheric sciences, and Kimberley Davies, Dalhousie University postdoctoral fellow.
“We are now challenged to develop a program that combines scientific effort and conservation policy that is sustainable and adaptive,” said Meyer-Gutbrod.
The North Atlantic right whale population currently hovers around 500 animals, with about 20 percent being reproductive females. This small, highly endangered population cannot sustain elevated mortality rates for long.
Studies from 1980 to 2012 showed that the right whale population was gradually increasing. More recent population models, which include demographic data through 2015, indicate that the right whale population has entered a period of decline, Meyer-Gutbrod said.
Marine experts know most, if not all, of the whales by name or number. Researchers observed only five North Atlantic right whale calf births in spring 2017, and zero births in spring 2018. If the dramatic increase in right whale mortality rates observed last year persists, the population will decline to extinction in 30 to 35 years, Meyer-Gutbrod said.
Canadian government agency Fisheries and Oceans Canada has an updated 2018 plan to protect right whales in the Gulf of St. Lawrence by including mandatory speed reductions for vessels greater than 20 meters (65.5 feet) long, closing snow crab fisheries early to prevent equipment entanglement, and creating areas where no snow crab or lobster harvesting gear is permitted.
Additionally, the scientists suggest restoring the now-defunct Continuous Plankton Recorder Survey program in the Gulf of Maine to monitor prey conditions for the right whales in their traditional foraging areas. Right whales typically need to consume over 2,500 pounds of plankton daily, but the southern distributional range of their preferred prey species may be shifting northward with warming ocean temperatures.
The scientists also suggest: increasing vessel-based, aerial and passive-acoustic monitoring; examining the management area strategies for fisheries and shipping channels in the Gulf of St. Lawrence this summer; testing fishing gear modifications to reduce entanglement risks; and finding ways to minimize the overlap between sojourning whales and fishing gear in space and time.
“The mounting pressure from a warming and increasingly acidified ocean requires timely implementation of adaptive conservation and management policies to protect ocean ecosystems and their living inhabitants,” said Greene.
Added Meyer-Gutbrod: “As it has in the past, the fate of this iconic species – and the ecosystem upon which it depends and contributes – will be determined by policy decisions.”
Meyer-Gutbrod was funded by Cornell’s Atkinson Center for a Sustainable Future and by the National Defense Science and Engineering Graduate Fellowship Program of the Department of Defense. Greene was supported by the Atkinson Center and the Office of Naval Research.