Rare Right Whales Gather in Cape Cod, Possibly Driven by Climate Change

Northern right whales have returned to Cape Cod in numbers not seen in recent decades. Public Domain

Nearly half of the approximately 500-some remaining right whales have been spotted in Cape Cod over the past few years—and now dozens of the critically endangered animals have congregated in the area as spring approaches and their main food source, plankton, begins to grow in abundance there. This is a change from two decades ago, when much smaller numbers of the creatures were sighted in the region.

Centuries ago, thousands of right whales were commonly seen in the waters of Cape Cod in springtime as the water warmed and plankton increased. But whaling here and elsewhere throughout the north Atlantic decimated numbers of the creature, known as the "right" whale for whalers because they were the "right" whale to hunt: They move slowly, often congregate near the shore and float after being killed.

The recent increase in right whales in the region is "rather extraordinary and somewhat mind-blowing," Charles "Stormy" Mayo, a right whale biologist at the Center for Coastal Studies in Provincetown, Massachusetts, told the Associated Press.

They are typically found farther out to sea, in the Gulf of Maine. Mayo theorizes that their return to these coastal waters may have to do with shifting ocean currents, spurred by global climate change, that are increasing levels of plankton off Cape Cod.

When researchers spot right whales, they report their location to federal authorities, which alert mariners. Federal law dictates that it is illegal to come within 500 yards of a right whale. Vessels must slow to 10 knots, or about 11.5 miles per hour, when the animals are near. Ship strikes are a leading killer of the critically endangered animals, as well as entanglement in fishing gear.

"They are a lot rarer than tigers, and elephants, and other big-time animals. I think it's an important thing to note every time" their numbers off Cape Cod increase, Mayo told The Boston Globe. "Everyone who lives along the coastline is dealing with a nearly extinct species. It's a last-of-the-dinosaurs kind of thing."