GORDON WARING, NEFSC/PROTECTED SPECIES BRANCH UNDER PERMIT #17670-02
Seal pups spend part of their first month in a lethargic state, making them easy to capture for testing.
CHATHAM – One of the world’s biggest gray seal colonies is off the coast of Cape Cod at Monomoy and off Nantucket on Muskeget Island and winter is pupping season, making it the best time to study the colony.
Gordon Waring, a scientist with the National Oceanic Atmospheric Administration’s Northeast Fisheries Science Center, was working in January on an eight-day field study of the seals with scientists from the Massachusetts Institute of Technology.
“We generally know the pup population, the gray seal population is increasing. We don’t know what the rate of increase is and part of the data we’re collecting from this work is the molting stage of these animals,” Waring said.
Waring heads the seal research program at the Northeast Fisheries Science Center’s Woods Hole Laboratory and is a co-chief scientist for the project. He is leading the team on Monomoy.
GORDON WARING, NEFSC/PROTECTED SPECIES BRANCH UNDER PERMIT #17670-02
Hundreds of seal pups are tested, weighed and sampled as part of the research. Here a researcher covers the head of a seal pup with a blanket to calm the animal while they take samples.
He and other researchers spent time capturing, tagging, sampling and releasing weaned gray seal pups on Monomoy and Muskeget. This winter’s study is focused specifically on learning more about the influenza virus in the gray seal population.
“The 2015 work continues a long-term collaborative project to understand the health and population of gray seals,” Waring said. “We hope to expand sampling at other pupping sites in US waters in future years.”
Muskeget is a privately owned and uninhabited island several miles northwest of Nantucket. It is the largest gray seal breeding and pupping colony in the US. Nearby Monomoy National Wildlife Refuge is an island off Chatham that is also a primary gray seal haul-out on the US East Coast although the number of pups born there is much lower than on Muskeget.
Scientists also want to learn more about the stock health, gray seal ecology and habitat use. Data was also gathered on the size of the population in order to detect demographic changes.
The goal of the research was to tag 200 pups, 150 on Muskeget and 50 on Monomoy.
GORDON WARING, NEFSC/PROTECTED SPECIES BRANCH UNDER PERMIT #17670-02
Researchers test gray seal pups this month on Monomoy.
“It’s obvious from looking both at our monitoring surveys of adult populations from aerial surveys and from the work we’re doing with the pups and the fact that the number of pup colonies is expanding and the number of pups being born is also increasing,” Waring said.
Mid-December to early February are the prime pupping months for gray seals. Gray seal pups that have been weaned remain on the islands for several weeks until they molt or shed their white coat for a darker coat.
Once captured, each weaned gray seal pup is measured and weighed. Biological samples, including blood, mucous swabs, hair and skin are being taken for use in health assessments and for other research. All seals that are studied have also been outfitted with numbered flipper tags for identification.
CCB MEDIA PHOTO
NOAA Fisheries Scientist Dr. Gordon Waring
In addition, one to three seals are being fitted with satellite tags that will gather and report data on movements and behavior over time.
Once the biological sampling and tagging work is completed, the seals are released. The entire process for each seal, from capture to release usually takes about 10 to 15 minutes, or up to 30 minutes if a satellite tag is attached.
Waring said the research has already given them some information on the health of the colony because of its expanding size. “That tells us that there are sufficient food resources available for these animals. We’re not seeing any starving adults. We’re not seeing animals with bad body condition, so given that, they are finding sufficient food,” Waring said.
Waring said a seal’s diet varies. “Their diet is very diverse. They pretty much eat most of the fish species that we find in this area, in New England’s Mid-Atlantic area,” he said.
To hear Dr. Gordon Waring discuss his study of the Monomoy seal colony, listen below.
