By Jonny Lupsha, Wondrium Staff Writer
A young harbor seal said “No thanks” to life in the ocean, opting for the Hudson River. Officials believe he was abandoned as a pup before making the unprecedented move of living life inland. Seals are carnivorous marine mammals.
Wildlife officials are stunned by a young harbor seal who has chosen to make his home on the Hudson River near the Saugerties Lighthouse. It’s believed that its mother abandoned it in Maine before it was cared for in Connecticut and released to the wild, at which point it chose to live on the Hudson. Even after it later went missing, it was found and returned to the ocean only to go back to its home 100 miles upriver.
Seals are marine mammals belonging to an order known as the Carnivora. In his video series Oceanography: Exploring Earth’s Final Wilderness, Dr. Harold J. Tobin, Professor in the Department of Earth and Space Sciences at the University of Washington in Seattle, says this family also includes other familiar land mammals.
Seals vs. Sea Lions
“The Carnivora are dogs, cats, bears, and weasels—all the animals like that—but the pinnipeds are the seals and the sea lions and the walruses and the fissipeds and the sea otters that swim in the sea,” Dr. Tobin said. “All of these are relatively recent arrivals, at least in the evolutionary sense, in the ocean.”
Pinnipeds—seals and sea lions—are mostly marine living, meaning they spend almost all their lives in the water, but not quite. They head to land in order to mate, fight over mating, and birth their young. Then they head back into the water for everything else. Seals and sea lions look very similar, making it challenging to tell them apart.
“The difference between seals and sea lions is something you’ve probably learned somewhere but forgotten multiple times; seals have no external ear parts whatsoever, a more streamlined shape,” Dr. Tobin said. “They swim with a fused set of hind limbs that’s essentially turned into a single flipper and don’t swim with their forelimbs at all, while sea lions have external ears—they look a little bit more dog-like in the face somehow.”
Sea lions’ hind limbs are still partially separated and they use their front flippers to swim. And, sea lions are more mobile on land.
It’s Hard Out There for a Pinniped
The largest seals are a species known as elephant seals. Their bulls can reach up to five meters in length and weigh 2,700 kilograms. That’s equivalent to 16 feet and nearly 6,000 pounds.
“All the pinnipeds, including the elephant seals, mate and give birth on land,” Dr. Tobin said. “Elephant seals [live] in large colonies with harems of females that are fought over by the alpha bulls for the opportunity to mate. Seals and sea lions can be seen on land, too, in many places, especially on the west coast—pulled out on piers and beaches and things like that, sunning themselves and pretty much ignoring the human beings that are paying attention to them.”
However, most seals and sea lions have difficult life cycles. According to Dr. Tobin, pups just like the one living on the Hudson River gain their independence immediately after birth, making their way to the sea from the beach much like baby turtles. When they get there, they’re prey to sharks and other predators. They only have about a one in five chance of surviving to maturity, which comes at six to eight years of age.