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Everything Is Going Wrong for North Atlantic Right Whales This Year https://ift.tt/2IWICIh North Atlantic right whales are living the plot of a science fiction story: They are not having any babies. With the end of the winter calving season just around the corner, so far zero newborns have been spotted. With fewer than 450 of the whales remaining, and around 100 breeding females, this reproductive drought is the worst-case scenario for the imperiled species. Brian Sharp, Marine Mammal Rescue and Research manager with the International Fund for Animal Welfare (IFAW), told Earther that the calfless season adds to a disturbing trend of sub-par years for the whales , and that it’s “becoming more and more apparent how dire the situation is.” Advertisement “The worst-case scenario is right now, we are there,” he said. “We’ve seen 18 known mortalities since 2016, and one of the things we know is that for every known mortality, whales die that we will never see.” North Atlantic right whales have been on the endangered species list since 1970 after being hunted to near-extinction by commercial whalers in the late 19th century. It looked like they were on a slow and steady rebound until about a decade ago. Since then, their numbers have started to come down due to a combination of environmental changes, entanglement in fishing lines, and encounters with ships. While the whales have averaged about 17 births per year over the last 30 years—with just one calf spotted in 2000, but 31 the next year—births have been below average for the past five years. If this trend doesn’t reverse soon, it will be hard not to consider extinction a real possibility. Advertisement Sharp said that low calving years are to be expected, but if the 100 or so breeding females are not reproducing pretty regularly, then the species is in deep trouble. With whales being apex marine animals, their decline or success is indicative of our overall progress at protecting the ocean, according to Sharp. “They show us the health of the ocean,” he said, “and if we can’t preserve the species, then the oceans are failing.” North Atlantic right whales typically give birth off the southeastern coast of the U.S. between December and March before returning to their feeding grounds in the northeast in mid-April. Last year, two previously unseen babies were spotted in Cape Cod Bay after the migrating to the feeding grounds, and scientists will be watching closely for any potentially unnoticed newborns. Advertisement But not even their feeding grounds are reliable anymore. As the Gulf of Maine warms due to climate change, their traditional food supply—tiny crustaceans called copepods—is shifting to waters with less strict protections from fast-moving ships and other threats. As Earther previously reported, under conditions of abundant prey, an average of just 13 human-caused deaths per year could cause North Atlantic right whales to decline toward extinction. But if the amount of prey in the ocean is reduced, toward levels similar to those seen in the 1990s, just 10 additional right whale mortalities annually could spell doom. Last year’s unusual mortality event, in which there was a total of 17 confirmed dead stranded whales—12 in Canada and five in the U.S.—easily exceeded these worrisome thresholds. Sharp said when the whales are forced to go to different areas at different times of year to find food, “they are not going to have that protection, that dynamic management system” that was developed over years of surveys. Regina Asmutis-Silvia, Executive Director of Whale and Dolphin Conservation North America, told Earther that as the climate changes and food supplies shift, right whales may not be getting the best sources of food, either. She said this is just one of a combination of factors causing her to grow increasingly concerned for the viability of the species. Advertisement For instance, Asmutis-Silvia said that even when the whales don’t die from entanglement, the stress can impact their ability reproduce. “Entanglements can impact the female’s ability to feed, leaving her in poorer condition so she can’t calf, or it could also be the physical stress from the entanglement that increases her stress hormones and puts her in poorer condition,” she said, adding that ocean noise can also increase stress and inhibit reproduction. Bottom line, according to Asmutis-Silvia, is the need to stop killing the whales faster than they can reproduce. Advertisement “It’s all human causes so it is all up to humans to fix them,” she said. In her opinion, it’s morally unacceptable for two affluent nations, the U.S. and Canada—which both have the means and legal mandate to protect the whales—to willingly allow them to edge closer to extinction. Preventing these unnecessary deaths can be done by taking measures to reduce fishing gear entanglements, reducing ship speeds in vulnerable areas so collisions are non-lethal, and enacting better monitoring and warning tools. Many of these initiatives remain voluntary in the U.S. and Canada, but as the degree of the problem becomes more apparent, federal and state authorities along with researchers and fishing and shipping industry members are looking for effective ways to better address the issue. “Perhaps right whales will finally be the species that grabs the public’s attention and makes everyone take notice about the growing number of threats facing the ocean and its inhabitants,” she said. Perhaps. Digital Trends via Gizmodo http://gizmodo.com March 28, 2018 at 09:30AM
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