A newly released study says a combination of warm waters and infectious diseases has been determined as the cause of a die-off of populations of sunflower starfish along the Pacific coast.
Study co-author Drew Harvell, a Cornell University professor of ecology and evolutionary biology, says the heat wave in the oceans caused by global warming is making the sea star wasting disease worse and killing the starfish faster.
The sunflower star is the starfish equivalent of a Tyrannosaurus—a huge, voracious, unmistakable alpha predator. With a three-foot diameter, up to 26 arms, and hundreds of tubular feet, it runs down clams, sea urchins, and snails at a top speed of six inches a second.
They were very commonly found near coasts. But since 2013, the sunflower star has largely vanished from most of its former 2,000-mile range; only in Alaska do appreciable populations still remain. In just a few years, an emerging disease has caused the continental-scale collapse of a once-common species, and has started to remake the underwater world.
The National Oceanic and Atmospheric Administration have snuffed showed that from 2013 to 2015, the sunflowers completely disappeared from the deep waters off of California and Oregon, and declined by 99.2 percent near Washington. In 2016, NOAA researchers couldn’t find a single individual in almost 700 trawls. This past summer, they saw just one.
They are a keystone species. In the absence of the sunflowers, the sea urchins they hunt are running amok, eating their way through the Pacific’s kelp forests. Kelp is a tagliatelle-like seaweed whose meter-tall fronds shelter vast communities of marine life. If the kelp forests fall, an entire ecosystem will fall too, including several commercially important species such as abalone, crab, and countless fish.
Warm waters could have either boosted the growth of whatever microbe is behind SSWD or stressed the sunflowers, making them more susceptible to infections.
Climate change is making species vulnerable to bacterial infections. There have been several reporting of such incidents around the world. Not just humans, the life on the planet is at risk.