There is evidence to suggest that climate change is contributing to the decline of several starfish species in North America. Elevated sea temperatures and ocean acidification, both consequences of climate change, have been linked to mass mortality events and disruptions in the reproductive cycles of starfish.

Sea stars, also known as starfish, play a vital role in maintaining the balance of marine ecosystems by controlling populations of prey species such as mussels, barnacles, and sea urchins. Their decline can disrupt the food chain and have cascading effects on other marine organisms, including fish, seabirds, and marine mammals.

In particular, the sunflower sea star (Pycnopodia helianthoides), found off the Pacific Coast of North America, has experienced significant population declines since 2013 due to a disease known as sea star wasting syndrome. While the exact cause of this disease is still being studied, research indicates that warming oceans due to climate change create favorable conditions for the proliferation of the pathogen responsible for the syndrome.

Another species affected by climate change is the ochre sea star (Pisaster ochraceus), common along the Pacific Northwest coast. Warming sea temperatures have been associated with larval mortality and developmental abnormalities, leading to recruitment failure and population decline.

While multiple factors may be involved in the decline of starfish populations, the evidence suggests that climate change is playing a significant role by altering ocean conditions and disrupting the delicate balance of marine ecosystems.