(March 22, 2013) Although its possible causes are still undetermined – climate change is a leading candidate – the appearance of seals, porpoises, and sea turtles on the Maryland coast and even further south, is intensifying, according to officials from the Baltimore-based National Aquarium.
“They’re starting to see seals travel further and further south, and they don’t have rehabilitation facilities in the Carolinas for them, so we’re shuttling the animals up here,” said Jennifer Dittmar of the aquarium’s Marine Animal Rescue Program.
Dittmar, who delivered a talk on stranded marine animals Tuesday at the Greater Ocean City Chamber of Commerce, said while the “seal season” in the resort area used to run from December to April, it has been gradually lengthening.
“It’s been getting later and later lately,” Dittmar said. “They’ll stay into May if our waters are cool enough to support them.”
Most species of seal, including the four most commonly seen in Maryland waters during the winter and late spring, typically dwell in colder, more northern waters. But the warming of these waters, some have theorized, is acclimating the marine mammals to travelling into more temperate climates during their breeding season in winter and early spring.
Under federal statutes, it is illegal to harass or disturb a marine mammal or endangered marine species, which is why the general public is advised to keep its distance from them and contact natural resources or wildlife authorities.
In the particular case of seals, the animals often “haul out” of the water and onto the beaches to rest during their increasingly long seasonal journeys.
“We don’t’ want to cause the animal stress if it’s just trying to rest and be a seal,” Dittmar said.
The most important judge of whether a seal is resting, is injured or in distress is by its posture, Dittmar said.
“A normal resting seal prefers to rest on its side, with its head and flippers in the air, kind of like a banana,” Dittmar said. “It kind of looks uncomfortable, but this is a normal posture.”
Photos of the animal, showing its posture, can often help rescue officials decide on a response.
“If you only have once chance to take a picture of the animal, the first thing I’ll want to look at is the posture,” Dittmar said.
The most common species seen in the area are the grey seal and harbor seal, which are fairly easy to distinguish for the trained eye.
“They grey seals have a long muzzle, more horse-like. The harbor seal has more of a puppy-dog face to it,” Dittmar said.
Most seals seen in the area are juveniles, having been weaned and left their mother, but not yet full adults. Although they travel through Maryland waters during the mating season, there is no evidence so far that seals actually give birth here.
“We haven’t yet, for Maryland, seen true nursing pups, either harbor seals or grey seals,” Dittmar said. “So far, all the pups we see are weaned. We don’t appear to have any true pupping grounds.”
The Mid-Atlantic coast has also been seeing increasing numbers of harp seals and hooded seals, Dittmar said, although these species are known to reside on ice floes and are thus extremely far south of their typical range to be seen in Maryland.
Although seals pose little danger to humans, those in adverse scenarios may be unpredictable, which is why the National Aquarium recommends keeping one’s distance.
“The adult male hooded seals are actually considered to be one of the most aggressive seals,” Dittmar said. “None of these animals is actually going to chase you down … with the exception of the adult hooded seal.”
In one recent incident in Assateague, Dittmar said, park volunteers attempted to corral a hooded seal found in a parking lot back onto the beach using sheets of plywood.
“It apparently charged the boards and bit right through the plywood,” Dittmar said.
In contrast to seals, which are typically healthy and even aggressive when seen on area beaches, whales and dolphins – the cetacean family – as well as sea turtles are more often sick or injured and can become defensive.
“Unlike our seals, that are comfortable on the beach in the winter, cetaceans and sea turtles cannot support themselves out on the beach,” Dittmar said. “Immediate changes to their organs happen when they’re on the beach. Things become bruised and shut down.”
In the case of porpoises, first responders are often advised to provide a shelter – a sunshade in the summer, or a windbreak in the winter – for distressed animals. Covering the animal with damp towels is also helpful, although caution is advised.
“These animals are basically one long muscle,” Dittmar said. “You need to be very careful when approaching them. The best way to do so is from the side and to the rear. You’re trying to approach the zone where the animal can’t see you as well and you’re in less of an impact zone.”
Sea turtles found on area beaches are typically injured or already dead, although it has recently been discovered that the animals are attempting to nest, due to the slight warming of local waters that are normally too cold for turtles.
One such clutch of eggs was laid on the beach at Assateague last summer, and was dug up after researchers believed none of the eggs had survived.
“We got about half way through and realized that there was a live hatchling in the nest,” Dittmar said. “It was basically all temperature driven … it should have hatched well before then [if the temperature was warmer]. It looks like there’s a trend in sea turtles shifting towards more northerly beaches.”
Anyone spotting a beached animal is encouraged to call the state’s hotline for sea turtles and marine mammals at 1-800-628-9944.