A team of scientists funded by NOAA’s Office of Ocean Exploration and Research recorded the distinctive calls of endangered North Atlantic right whales in an area where it was believed that the historic resident population was hunted to extinction in the early 20th century.
In July 2007 scientists from NOAA’s Pacific Marine Environmental Laboratory, NOAA’s National Marine Mammal Laboratory and Oregon State University deployed hydrophones and kept recording sounds over a full year in the Cape Farewell Ground, an area off the southern tip of Greenland. Five stationary hydrophones were placed between 200 to 400 miles off the coast of Greenland.
After collecting them in July 2008, the team sorted through the year’s worth of recorded sound on each device to find evidence of right whales. Using automated detection software to search for a particular right whale sound – an “up” call – and after months of sifting through false positives, they identified more than 2,000 real whale calls. All of the calls occurred between July and December, with evidence between July and September of a north-south migration that project Chief Scientist David Mellinger believes covers thousands of miles.
There are two possibilities as to which group the recorded right whales belong to: they could have migrated from the western North Atlantic right whale population, which is estimated at between 300 and 400 animals. But of the two right whales sighted in the last 50 years on the Cape Farewell Ground, one had only rarely been seen with the western population, and the other had never been seen in the area. The recordings in the Cape Farewell Ground raise the possibility that the eastern North Atlantic right whale population may still exist.
Besides providing a better understanding of the whales, the discovery has implications for future shipping in the region. Knowing that the whales are in the area is important, as continued ice melt will likely lead to increased shipping in the region. “Newly available shipping lanes through the Northwest Passage would greatly shorten the trip between Europe and East Asia, but would likely cross the migratory route of any right whales that occupy the region,” said Phillip Clapham, a right whale expert with NOAA’s National Marine Mammal Laboratory, who participated in the study. “It’s vital that we know about right whales in this area in order to effectively avoid ship strikes on what could be a quite fragile population.”
“This discovery adds important information so that ocean resource managers may better understand and better protect this highly endangered species.” said Jane Lubchenco, Ph.D., under secretary of commerce for oceans and atmosphere and NOAA administrator. More research will be conducted to estimate the number of animals as well as to understand what population they belong to.
Copyright © 2009 by Marine Science Today, a publication of OceanLines LLC