Wednesday , October 16 2019
Home / unitedstates / The "Unprecedented" epidemic wipes off the marine stars in the West Coast

The "Unprecedented" epidemic wipes off the marine stars in the West Coast



Underwater photography of a sick and dying sunflower star.
Photo: Edward Goulexon

In 2013, marine scientists witnessed a real, aquatic version of Infected. In the summer, divers in Monterey, California, were treated in a terrible scene of marine stars with limbs exterminated and decomposed bodies. Soon, large aquariums up and down to the West Bank reported that their marine stars had gone from health sections to weeks. The beaches are flooded with dead and dying starfish or their remains.

Scientists knew little about the disease that made them lose them. While its origins remain a mystery, new findings show that it is turbulent by miraculously hot water from the West Coast of the United States from 2013 to 2015. The research, published on Wednesday in Science for Progress, also reveals how dramatically reshaping marine star communities along the coast, including the deletion of sun-kissed stars from large parts of their range. The impacts show how infectious diseases and climate change can communicate in terrible ways, and that in the oceans, these impacts could strain us.

"A disease that consumes more than one starfish is one of the most extensive marine outbreaks of wildlife," said Drew Herwell, an ecologist for infectious diseases at Cornell University, for Robert. "This is an impressive example of a multi-host disease that basically reshapes our underwater ecosystem."

Harvell and her fellow researchers used nearly 20,000 observations collected from diving and towing from 2004 to 2017 to deal with the starfish population from California to Alaska, including British Columbia. The chronicle data are abundant with a starfish before and after the onset of the disease. They also retrieved satellite temperature data to review its relationship with the dying starfish.

The results show that after the disease arose in 2013, the starfish population fell from a rock. And when the Pacific got super heat thanks to blob in 2014, dying-off got even extreme.

"It was shockingly fast in its progression and unprecedented in the number of species that were affected," said Harvel.

An underwater photograph showing the initial appearance in Sackinaw Rock, BC, Canada. The two photos were separated for 20 days at the same location in October 2012.
Photo by Neil McDonald

In total, 20 species of marine stars have been affected by the disease, but the study focuses on a starfish with sunflower. In the 2000s, they were certainly found up and down along the shores of dozens or even hundreds of colonies. But since 2014, they have virtually been eradicated. The findings show a 100 percent decline in biomass in large parts of coastal California and Oregon, 99.2 percent in Washington and 96 percent in British Columbia. It's all fancy in a way to say that they were basically completely wiped out.

"There is a lot of sea bays here from Mexico to Alaska, and to say that its threat to Alaska is a rather shocking thing," said Harvel.

While the disease is likely to cause chaos, it is clear, however, that the hot waters that cooked the coast have accelerated the death of the stars. The Pacific Ocean reached up to 7 degrees Celsius above the perpendicular to the top of the hole, which not only affected the stars, but also a whole range of other types of algae to crustaceans.

"For correlation with rising water temperatures, I think the data are as sound as they can, given the limitations of data collections," says Melissa Minner, a researcher at the University of California, Santa Cruz, who also studied the star-from , he told ESER. She praised the study as a whole, but pointed to the need for direct water observations to really develop in exactly how the marine star spends illness and hot water interaction.

Some studies show that climate change has played a role in the creation of the hole, and damn well causes the oceans to heat up as a whole. This increases the risk of catastrophic impacts on ecosystems, especially for diseases and invasive species that progress in warm water.

Sunflower star is a characteristic species, eats urchins and maintains the balance of the ecosystem. His absence allowed the urchins to multiply and understand algae, which means fish, crustaceans and other species are losing their habitat and will perish or migrate. This is what environmentalists call a trophic cascade and has direct impacts on humans on land, especially fishing operations that rely on a functional ecosystem and fish to exist.

Harvell says that with a sunflower sea star that has largely moved along the West Coast, the main hope for its recovery is that populations in Alaska are still moving together. One possible way forward is their growing in captivity to ensure a viable population, while researchers are trying to discover the cause of the starving starvation disease. Other stars show some signs of recovery and can also help researchers understand what happened and prepare for when the next catastrophe of the oceans will inevitably strike.


Source link