Orcas, the friendly, personable killer whales that hang out in the waters of Puget Sound just west of Seattle, Washington, have had a rough couple of years. Lack of food, the abundance of toxins in ocean waters and noise from boats have pushed them to the brink of extinction in the Pacific Northwest.

This month, the Center for Whale Research announced that three more killer whales had died since last year, bringing the total number of orcas in this southern group to 73.

They are divided into J, K and L “pods.” There was great excitement July 5 when two of the major “pods” in the southern group showed up off San Juan Island in Puget Sound. Swimming with the J pod was a baby, J56, born around May 24. There was also another baby, L124, born to the L pod in January.

Images of orcas are all over the Pacific Northwest. Local Indian tribes consider them to be spiritual relatives. Seattle’s metro-bus cards are called Orca passes.

Last summer, international attention was focused on a female orca, J35. Also known as Tahlequah, she birthed a six-foot-long calf who lived only a half-hour. Instead of letting it sink to the bottom, the mother swam about the sound for 17 days balancing the dead calf, which weighed hundreds of pounds, on her head. Images of the mourning whale refusing to leave her baby transfixed the world.

That September, J50, or Scarlet, another female orca in the southern group, died of starvation. She had been fading for months, and in desperation, a team of veterinarians and biologists tried feeding her antibiotics via a dart. They were planning to capture her in a last-ditch effort to save her life. Instead, she disappeared.

After outraged residents demanded action, Washington State Governor Jay Inslee, a Democrat, put together an orca recovery task force. He signed some of their recommendations into law in May but didn’t deal with a major problem affecting the killer whales: four dams on the lower Snake River in which Chinook salmon — orcas’ favorite food — used to spawn. There has been a shortage of the salmon in overfished Puget Sound. Removing the dams would allow the salmon to lay eggs on miles of streambeds. But the government would need to find another source for the energy the dams create.

Deborah Giles, director at the nonprofit Wild Orca, says the killer whales’ situation isn’t going to improve until there is more for them to eat. She said the state needs to set aside a number of fish for the orcas before they figure out how many fish humans can catch.

“I think of the whales as the original harvesters,” she said. “They were here foraging on salmon before humans were here. In 50 years, we have completely decimated their food source.”

The killer whales have been spotted a lot less in Puget Sound this summer, preferring the ocean waters off British Columbia that have more food. Until more fish are available in Puget Sound, the orcas may stay away from what used to be their summer home.