ANCHORAGE, Alaska (AP) — Federal researchers in the Bering Sea have made contact with one of the rarest whales on Earth.

National Oceanic and Atmospheric Administration scientists photographed two animals in the eastern stock of North Pacific right whales and obtained a biopsy sample from one.

Just 30 to 50 of the critically endangered animals remain from a population largely wiped out by whalers.

NOAA research biologist Jessica Crance used an acoustic recorder to hear faint sounds Sunday of a right whale west of Alaska's Bristol Bay.

After more than four hours, a research vessel reached the whales.

Phillip Clapham of the Alaska Fisheries Science Center in Seattle says the sampled whale was last seen a decade ago.

He says the biopsy sample can reveal the whale's gender, sexual maturity and diet.