Orcas struggle to survive

The people who are dedicated to saving the southern resident killer whales are not quitters, but their task seems increasingly bleak. A new calf died on Tuesday, the most recent in a sad list of deaths. The calf was the first born in three years to the southern residents, but it was in trouble from the start. Its mother tried to push it to the surface to give it a chance to breathe, but nothing worked.

“The baby was so newborn it didn’t have blubber. It kept sinking, and the mother would raise it to the surface,” Ken Balcomb, senior scientist with the Center for Whale Research on San Juan Island, told the Associated Press.

The southern residents were listed as endangered in the U.S. and Canada about 10 years ago, as their numbers dwindled. In 1995, there were 98. Today, there are 75.

Several years ago, a baby boom sparked hope of a resurgence, but half of the 11 calves from that boom have died.

Toxic pollution and disturbances from boats are significant threats, but the main danger is a lack of chinook salmon, which are the southern residents’ main source of food. Without those fat-rich fish, the orcas have trouble with pregnancy. One study found that between 2007 and 2014, two-thirds of pregnancies failed.

The federal government announced it was closing some commercial and recreational chinook fisheries on the West Coast to help maintain the orcas’ food supply. The Americans are looking at increasing hatchery production. But it’s not clear that these steps will work or what other options might be successful.

If the strategies do work, they will take time — which is running out for the southern residents.