The highlight of this winter week around New York Harbor was the sight of another starving and smart gull with food in its beak. Last week I observed a Herring Gull with a sea star, this week brought a Lesser Black-Black bent on catching a crab.
Although we have all become used to seeing gulls on the beach, there is more here than meets the eye. The birds are really fun to watch during the winter when most other coastal life has gone south. Gulls are hardy and bright birds that seem to savor stormy winter weather. Many gulls are able to fly long distances even in windy conditions, dive into chilly waters with lots of chop, and take off with few wing beats. They can live in intense cold temperatures. Many gulls are omnivorous and opportunistic feeders, able to forage on foot, while flying or even while swimming. Gulls are remarkable birds that are perfectly adapted to live with humans in the stressful and often demanding surroundings in New York Harbor.
Watching gulls catch food is like watching a person go fishing. You never know what they will catch, and what does get hooked often represents a quick peek on who's home in the water and what they are up to.
The other day I visited the Borough of Highlands, a small coastal community located along Sandy Hook Bay. The tide was low, the sun was bright, the wind was calm, and the temperature was cold. While walking near the edge of the bay, I watched around 50 gulls, including Herring, Ring-billed, and Black-backed, resting and preening. A lazy morning along the bay it first seemed.
It didn’t take long, though, for one hard-working bird to change the serenity. Out of nowhere an adult Lesser Black-backed Gull dropped down out of the bright blue sky to splash into the similarly bright blue water of the estuary. Up from the water I could see a crab in its beak. Here was breakfast. The crab was a huge female Blue-claw, complete with red nail polish on the tips of its claws and well over four inches in width, almost certainly legal size.
During the fall, adult female Blue Crabs, after mating with a male, will migrate into deeper and saltier waters of the bay, often congregating with other female Blue Crab near the entrance to the harbor, not far from the tip of the Sandy Hook peninsula. Many will bury themselves in the mud and muck of the bay to become dormant throughout the winter months to wait until the water warms up.
Females will develop an external egg mass, or sponge, beneath their aprons, and will spawn and release their eggs in the open ocean from May through August. Ocean currents will then spread Blue Crab larvae, called zoea, around to different estuarine waters, some will return back to the harbor while other zoea may travel to Long Island or south along the Jersey Shore. This journey of pregnant females and zoea occurs to help ensure the health and genetic diversity among the species.
None of this mattered to the hungry gull. It just wanted food. The bird pecked and punched at the crab’s exoskeleton near a sidewalk to get to the meat. Within minutes, the crab was exposed and devoured happily by its predator.
At about 21 inches long, Lesser Black-back Gulls are rare visitors to New York Harbor from Europe. They can usually be found in flocks with their slightly larger cousin, Great Black-backed Gulls. Lesser gulls usually have dark gray feathers on their back, while great gulls have a very dark back. Two big birds with few predators and plenty of bravado. This bird didn’t have to share its meal with any other animal, nor did any other gull even attempt to steal this bird’s breakfast. For at least a few moments, the Lesser Black-back was king of the beach.
Winter can often be a harsh time for many wild animals. Crabs and clams can become exposed by churning waves and strong winds. They are vulnerable and often eaten by ambitious creatures that are often larger or smarter than themselves. It’s a real life drama that plays out every day in New York Harbor.
For more information, pictures and year-round sightings of wildlife in or near Sandy Hook Bay and Lower New York Bay, please check out my blog entitled, Nature on the Edge of New York City at http://www.natureontheedgenyc.com