SEATTLE—Exceptionally skinny gray whales—enfeebled by starvation and mangled by blunt-force trauma—are washing up this spring along the coast of Washington state in numbers that alarm marine-mammal scientists.

Twenty-two carcasses have been found so far this spring, many of them battered by collisions with boats. Dead and dying on beaches, in harbors and up narrow rivers, they are grim evidence of what researchers say is a population and fertility collapse among gray whales that has been worsening for seven years and is driven by climate change in the rapidly warming Arctic.

A surge in malnutrition-related mortality has cut the eastern North Pacific population of gray whales in half, to about 13,000 last year from about 27,000 in 2016, while reducing calf births by 95 percent, according to counts by the National Oceanic and Atmospheric Administration. This whale stock is one of the most studied in the world, and scientists say the current population nosedive has lasted longer than previous cycles of decline monitored over the past 60 years.

“The population is in serious trouble, and this is not part of a normal cycle,” said John Calambokidis, a senior research biologist and co-founder of the Cascadia Research Collective in Washington state. He has been studying gray whales for 40 years. “What is so alarming is that desperate animals are dying at a really high rate and not having calves.”