SEATTLE — For the last three years, not one calf has been born to the dwindling pods of black-and-white killer whales spouting geysers of mist off the coast in the Pacific Northwest.

Normally four or five calves would be born each year among this fairly unusual urban population of whales — pods named J, K and L. But most recently, the number of orcas here has dwindled to just 75, a 30-year low in what seems to be an inexorable, perplexing decline.

Listed as endangered since 2005, the orcas are essentially starving, as their primary prey, the Chinook, or king salmon, are dying off. Just last month, another one of the Southern Resident killer whales — one nicknamed “Crewser” that hadn’t been seen since last November — was presumed dead by the Center for Whale Research.

In March, Gov. Jay Inslee issued an executive order directing state agencies to do more to protect the whales, and in May he convened the Southern Resident Orca Task Force, a group of state, tribal, provincial and federal officials, to devise ways to stem the loss of the beloved regional creature. “I believe we have orcas in our soul in this state,” he said. At another point, he wrote of the whales and Chinook salmon that “the impacts of letting these two species disappear would be felt for generations.”