Seals along the shoreline

Story and photos by Jim Murtagh

Fighting to reclaim their place in the coastal ecosystem, it is estimated that 90,000 Western Atlantic harbor seals currently swim in the cool water off the New England coast. Once viewed as a threat to commercial fisheries, this stocky marine mammal was nearly wiped out by bounty hunting in Maine and Massachusetts. Presenting to a group of Menunkatuck Audubon Society members, Amy Ferland, a researcher at The Maritime Aquarium of Norwalk, said proudly “This is a success story for the Marine Mammal Protection Act which was enacted in 1972.”

The presentation provided the nearly thirty attendees at the Guilford Community Center with an introduction to the seals that are frequently seen off the Connecticut coast, and included a summary of the aquarium’s 2006 Seal Census Study. Photos and video clips of seals resting on rocky outcroppings in Hammonasset Beach State Park and the Thimble Islands delighted the crowd.

Ferland explained that in the summer, juvenile “ice seals” such as the hooded seal, harp seal, and the gray seal travel from the Arctic to Long Island Sound to explore new habitat and to avoid competing with adult seals for food and territory. It seems that grey seals have a particular affinity for Faulkner and Goose Islands. This group of seals is not frequently seen by beachgoers, but rather it is the next wave of seals that generate the most excitement along the shore.

Harbor seals migrate from Maine to Long Island Sound in the winter months and are a welcomed site along the CT coastline.

When the water temperature starts top drop, typically around November, adult harbor seals begin their yearly migration into the area from their summer feeding grounds in Maine. Casual observers may refer to the seals as seasonal visitors, but Ferland says “I don’t like to use the word visitor because it implies that they don’t belong here. These animals choose to stay here in Long Island Sound during the winter because it’s their habitat.” Harbor seals are temperate seals and cannot maintain breathing holes when Maine’s water becomes covered with ice.

The harbor seal is the most widely distributed pinniped in the world and has five recognized sub-species. Phoc vitulina concolor is the species which inhabits New England’s water. This adaptive, five foot long, 200 hundred pound animal can survive in sea water, brackish water and even fresh water. Light grey and silver in color, with abundant small dark spots, the harbor seal uses its short front flippers to crawl about sandy beaches and rock piles with caterpillar-like undulations.

According to Ferland, most seals migrate to “maximize their fitness,” which refers to finding food, habitat and possibly a mate. As habitat in Maine decreases due to changes in the ecosystem and growing seal populations, the harbor seal is expanding its range southward into Long Island Sound, New Jersey and as far south as North Carolina. Harbor seals along the Eastern U.S coast are unique in that they are the only harbor seals known to follow a regular migration route.

Female harbor seals are pregnant when they arrive in Connecticut and will spend the winter actively feeding. The seals will return to Maine in the spring to have their pups, but Ferland points out “most of her investment in the pup will be in areas outside of Maine.”

The 2006 Seal Census Study estimates that there are 3,000 harbor seals in Long Island Sound, with most found on the eastern shore. Madison has one of the largest seal populations in Connecticut. The census recognizes that for every seal observed, there are two more off-shore which were not identified. Using a combination of land, boat, and aerial surveying methods, Ferland’s data is showing a rebounding seal population all along the Connecticut coast. Fifty seals have been observed in Branford’s Thimble Islands on a single aerial survey photo.

An aerial photograph of the Thimble Islands in Stony Creek shows a healthy population of seals. (Photo provided courtesy of Amy Ferland).

Several factors have contributed to the seals’ success. The Marine Mammal Protection Act, a federal law that protects all marine mammals from harassment, disturbance, and human caused injury and death, put an end to bounty hunting. Fishery management has helped rebuild groundfish stocks of species such as the flounder and hake, upon which seals feed, and wildlife sanctuaries have been created that protect haul out sites.

Ferland has studied the diet of local seal populations by examining the undigested otoliths, tiny ear bones of fish, found in seal scat. Harbor seals are feeding primarily on red hake with a mix of flounder, squid and skate. While not a direct threat to commercial fisherman, some seals have learned to steal fish from nets, or may try to get at the bait bag in lobster pots, and in the process damage fishing gear. As far as being a risk to lobstermen or shell fisherman, Ferland says “They don’t eat shellfish. They’re not going to be eating your oysters or mussels. They are eating fish.”

Another aspect of Ferland’s research is studying what type of habitat harbor seals prefer to use for hauling out. She has found that the seals seek sheltered rocky sites to avoid being washed away in stormy weather, an additional reason the protected Connecticut shore may be preferred to Maine’s exposed coast. Her data indicates the best opportunity to observe seals are on calm, rain free days, at low tide. A key tool in her research has been a video camera which was installed in the light house lantern on Sheffield Island in Norwalk Harbor. The camera, which was partially funded by the Long Island Sound license plate campaign, broadcasts a live “seal cam” to the Internet so that anyone can watch for seals.

Harbor seals haul out at low tides and rest on exposed rock piles. (Photo provided courtesy of Sam Sadove).

An interesting behavior that the camera has allowed scientists to observe is that harbor seals “flush” (leave their haul out site and return to the water) more readily for approaching kayaks and small boats than for larger fishing or commercial vessels. Objects close to the water resemble a predator and elicit a stronger reaction from the seals. Ferland reminded kayakers that many of the seals seen in our area are pregnant, and that once the seal flushes from a haul out site, it might not return. This can put unnecessary stress on the seal and make it more vulnerable to predators. Kayakers should stay clear of known haul out sites or go out after low tide.

The best method to view seals is with a pair of binoculars or spotting scope. Since seals are a protected species, federal guidelines require that people approach no closer than 50 meters (164 feet). Harbor seals are particularly shy, and often retreat from approaching people at distances of several hundred meters. If you notice that the seals are watching you, do not move any closer. Seal watch cruises are a great way to experience the seals without endangering them.

If you want to learn more about harbor seals, the seal census, or to view the seal cam, go to: www.sealcensus.org If you observe live, dead or entangled marine mammals in Connecticut, do not approach or touch them, but instead call the Mystic Aquarium stranding line at (860) 572-5955 ext. 107. To learn more about the Menunkatuck Audubon Society and their presentations, go to: www.menunkatuck.org