Federal authorities say an increasingly deadly year for the endangered North Atlantic right whale got worse this week when another member of the species was killed in a collision with a ship. The population of giant right whales has fallen to fewer than 360. Vulnerable to ship strikes and entanglement in fishing gear, the whales have suffered high mortality in recent years. Several have died already this year off Georgia and Massachusetts. The National Oceanic and Atmospheric Administration says the most recent right whale to die was found floating 50 miles offshore east of Back Bay National Wildlife Refuge in Virginia Beach, Virginia, on March 30.