Monday, April 04, 2011

{Press} Right whales spending winter in the Gulf of Maine

The Working Waterfront | Dr. Heather Deese and Catherine Schmitt | March 30, 2011

"Dr. Moira Brown has spent the last 27 years following whales-our mammalian kin that long ago returned to the sea-as they travel throughout the North Atlantic Ocean. But the whale's carefully evolved adaptation to ocean life makes them difficult for humans to comprehend. What we do know is that many of the less than 475 remaining right whales visit the northern Gulf of Maine and Bay of Fundy every summer, and emerging research data suggest that right whales may stay in the Gulf after their feeding season to breed.

Right whales are now the world's most endangered whale; marine mammal biologists estimate that American whaling ships killed a total of 5,500 to 11,000 of the species during the centuries when the oil-rich whale was a primary target. By identifying areas where whales congregate, scientists hope to reduce mortalities from entanglement and ship strikes.

"Over the years we have found out more about where they go and what they do when they get there," said Brown. "Despite all the knowledge we've gained, there are three things we are still trying to figure out: mating grounds, nursery grounds-we know that some calves are born off the Florida coast between December and March, but we haven't located the second nursery area-and where do they go in the winter?"

The beginning of an answer emerged in 2004, when biologist Tim Cole of NOAA's Northeast Fisheries Science Center in Woods Hole expanded that agency's aerial whale survey of the U.S. side of the Gulf of Maine into the winter months.

Some 300 flights, mostly in spring, had already confirmed that the Great South Channel was a hotspot for right whales between April and June. The expanded surveys, flying at 750 feet, found right whales in November, December and January-as many as 70 in one day.

"After repeated sightings of sometimes many whales, we got the sense this was an important area, and the credit belongs to the huge aerial survey effort," said Cole.

The whales are located in an area "smack dab in the middle of the Gulf" between Jordan Basin, Jeffrey's Ledge and Truxton Basin-about 50 miles from shore due south of Penobscot Bay and Mount Desert Island, according to Cole.

"Before, we knew that the whales move out of the Bay of Fundy in the fall, and now we know that some of them only go as far as south as Jordan Basin," said Brown. "What was exciting about this find was that it was right in our backyard, which is always the last place we look."

Moira Brown needed a boat to get close enough to the animals to decipher their behavior. At a conference in Quebec in 2009, Tim Cole met with Brown and his friend and former classmate, Zack Klyver, who is also the head naturalist of the Bar Harbor Whale Watch Company.

Klyver grew up in Eastport, where his father made a living by farming salmon, catching groundfish and harvesting scallops and clams. Twenty years later, Klyver has taken thousands of people on whale-watching trips. He knew his company's boat would be the perfect vessel for winter whale surveys to Jordan Basin.

As any fisherman can tell you, winter is a dangerous time in the Gulf of Maine. Freezing winds and frequent storms make for harrowing sea journeys. The Friendship V, a jet-powered catamaran made by Incat of Australia for carrying tourists offshore, is fast, roomy and stable enough for scientific sampling work.

With a boat secured, and funding from the Canadian Wildlife Federation, TD Financial Group and the Marine Mammal Commission, Brown pulled together a survey team of six, and Klyver helped round up 20 volunteer observers, including fishermen from Canada and the United States. Ocean Properties, the parent company of Bar Harbor Whale Watch, provided free lodging to the right whale crew and volunteers, who made three voyages to the central Gulf in November and December.

The 40 or so whales they saw were familiar; Brown and her colleagues at the New England Aquarium and North Atlantic Right Whale Consortium have built a database of over 500,000 photographs that are used to identify individual right whales. Combined with genetic data from skin samples (with help from Brad White at Trent University and Tim Frasier at St. Mary's University), the database is gradually revealing the whale family tree. "The New England Aquarium's whale catalog is a very powerful research tool because it has the sighting history and life history of each whale-age, sex, parents," Cole explained.

"If this part of the Gulf of Maine was a mating ground, we would expect to see a certain demographic: females who are ready to get pregnant, and lots of males. This is what we saw," said Brown.

To tell whether whales are breeding or pregnant, Brown analyzes fecal matter for reproductive hormones, but there wasn't any present during their three trips to the wintering area in late 2010, suggesting that the animals were not actively feeding. "Is this because the animals weren't eating, or because they were mating and they don't feed when they mate?" questions Brown.

Andrew Pershing, a biological oceanographer at the University of Maine and Gulf of Maine Research Institute, has studied the relationships between ocean conditions, right whale behavior and the presence of Calanus finmarchicus, the right whale's preferred food. The tiny shrimp-like zooplankton is thought to be less abundant during November and December than in late summer and early fall, when rich stocks of Calanus float 150 meters below the surface and attract large numbers of feeding whales. Intense weather conditions caused Pershing's group to cancel a scheduled research cruise this November to sample Calanus levels later in the year.

In addition, the Maine Department of Marine Resources is awaiting analysis of whale movement data recorded between September and December 2010 by ten Marine Autonomous Recording Units or "pop-up buoys."

The speculation will continue until next winter, when Brown, Klyver, and their whale survey team and volunteers hope to return to the Gulf of Maine and Jordan Basin."

This article is made possible, in part, by funds from Maine Sea Grant. Heather Deese holds a doctorate in oceanography and is the Island Institute's senior programs director - marine initiatives. Catherine Schmitt is communications coordinator for Maine Sea Grant.

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