by Rebecca Chillrud
December 05, 2018
One of the Bay’s largest visitors is the humpback whale. These school bus-sized mammals are better known in the waters north of here—their scientific name, Megaptera novaeangliae, means “big-winged New Englander”—but there are at least a few sightings in the Chesapeake each winter. Humpbacks are known for their breaching displays, where they launch their bodies out of the water and come back down with a loud slap, so those that do visit our waters certainly make their presence known.
Humpback whales can live for 75 to 95 years and survive on a diet of fish, plant matter and plankton. Though they tend to be opportunistic feeders, eating whatever is readily available, they do have a few clever hunting techniques. The simplest is to lunge through large groups of plankton or fish with an open mouth. Extra water is pressed out, while the food is caught in the whale’s baleen plates—the whale’s bristly teeth-like structures—and eaten.
Other techniques are more elaborate. In one, the whale will swim in a circle on the surface, agitating the water to create a foamy circle. They then dive down and come up from below, capturing any prey within the circle. They may also use bubbles to help them hunt. In this case, the whale exhales to create clouds or columns of bubbles. The bubbles are thought to confuse and herd prey, immobilizing them or making them feel they are trapped in a net.
In whichever way they choose to capture their food, it’s always exciting to spot a humpback in the Chesapeake. Have you ever seen one here? Let us know in the comments.