In this March 28, 2018, file photo, a North Atlantic right whale surfaces in Cape Cod bay off the coast of Plymouth, Massachusetts. Credit: Michael Dwyer | AP

PROVINCETOWN, Massachusetts — Researchers have identified the first baby North Atlantic right whales to arrive in Cape Cod Bay for the spring.

The right whales are among the most endangered marine animals on the planet, and they number only about 400. Recent years of high mortality and poor reproduction have put the species in jeopardy.

The Center for Coastal Studies said it recently documented two mother/calf pairs in the bay, bringing the total number of calves seen this spring to three. The center said only 10 right whale calves were known to be born this season. One was struck by a vessel shortly after birth and hasn’t been seen since January.

The whales journey from calving grounds off Florida and Georgia to Cape Cod Bay every year. The center’s right whale ecology program director, Charles “Stormy” Mayo, said it’s “always a relief to see the mothers and their offspring arrive unscathed.”