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

Several conservation groups are suing the federal government in an effort to force new restrictions on ship traffic in areas where endangered North Atlantic right whales are present.

The Conservation Law Foundation, Defenders of Wildlife and others said the National Fisheries Service has failed to act on previous petitions asking for several rule changes. Those include expanding areas and times when a 10-knot speed limit goes into effect, making the limits mandatory instead of voluntary and including smaller vessels in the restrictions.

Roughly half of the whales — including calves — found dead in recent years have been victims of ship strikes, the groups said. The suit was filed in federal district court in Washington, D.C.

Meanwhile, federal fishing regulators have begun a series of virtual public information sessions on recently proposed rules that aim to reduce the risk that right whales will be entangled with lobster fishing gear. Two sessions geared to Mainers and businesses will be held next week.

This article appears through a media partnership with Maine Public.

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