In this April 10, 2008, file photo, three right whale tails surface in Cape Cod Bay near Provincetown, Massachusetts. Credit: Stephan Savoia / AP

An endangered species of whale that lives off the East Coast is having its best season for new babies in several years.

The North Atlantic right whale numbers only about 360, and it has been hindered in recent years by high mortality and low reproduction. But this year 18 newborn whales have been spotted, and that’s the best since 2013, Maine Public reported.

The calving season for the whales began in November and could continue through the month. The whales are vulnerable to ship strikes and entanglement in fishing gear. They’ve been the focus of conservationists for years.

Federal ocean regulators are expected to issue new rules designed to protect the whales in the coming months. The rules will change the way fishermen harvest lobsters off the East Coast.