Sunday , February 28 2021

As ocean temperatures rise, sea stars may not be the only ones affected by infectious disease




<div _ngcontent-c14 = "" innerhtml = "

A healthy sun flower star (Pycnopodia helianthoides) on a bed of surfgrass.Jacqueline Sones

In 2013 and 2014, a debilitating disease was demolished populations of marine stars from Mexico to Alaska. When a starfish is infected with wasting syndrome, white lesions appear on its body, the surrounding tissue decays, and its body finally disintegrates, causing the animal to perish, although it is understood that the loss syndrome of marine stars is caused by a viral pathogen& nbsp; (The "densovirus associated with the starfish"), it was not clear what caused the outbreak of the disease in the first place.And although many species of starfish have begun to recover, the charismatic populations of the star of the sun flower – which can grow up to 3 feet in diameter – continue to decline. & nbsp; Now, a new study suggests that ocean warming is likely to account for its continued absence on the Pacific coast.

"The numbers of the starfish have remained so low in the last three years, we consider them threatened in the southern part of their reach, and we have no data for northern Alaska," say& nbsp;Dr. Drew Harvell, Professor at Cornell University and lead author of this study.

A purple ocher star (Pisaster ochraceus) suffering from the disease of wasting.Jacqueline Sones

In deep water habitats, the sunflower star has been & nbsp;on the front lines Eleven years of data collected during diving in waters between Southern California and Alaska showed that sun-flowered stars were abundant before 2013 and that their populations declined sharply after the onset of the wasting syndrome. Scientists also found that the ocean had warmed by almost 39& deg;F within a period of four years at some locations within that range. But the unequal nature of this challenging to link temperature increases for the outbreak of debilitating disease. However, Dr. Harvell and his colleagues were able to demonstrate that the population of the sunflower star recorded unusual heating patterns in the Pacific Ocean.

"It is important to remember that disease is a normal part of marine and terrestrial ecosystems," Dr. Colleen Burge, who study marine diseases& nbsp; but was not involved in the study of the star of the sun flower, "Many factors, including man-made change, can improve disease transmission in the ocean and on land. "

In recent years, the Pacific Ocean has & nbsp; experience & nbsp;record highs& nbsp; and & nbsp;marine heat waves& nbsp; that are It is expected to become more common as climate change intensifies. A hot period in the 1980s caused a major outbreak of shriveling foot syndrome& nbsp; between the abalone species and eventually caused the black abalone to become a endangered species protected by the federal. And there is evidence that climate change will also affect diseases in corals, mollusks, sea grasses, fish and marine mammals.

"Of course, none of this happens in a vacuum," says Dr. Burge, "Other human cause factors can cause disease or be a co-factor in disease transmission in this rapidly warming era."

& nbsp;

">

A healthy sun flower star (Pycnopodia helianthoides) on a bed of surfgrass.Jacqueline Sones

In 2013 and 2014, a devastating disease demolished populations of marine stars from Mexico to Alaska. When a starfish is infected with the waste syndrome, white lesions appear on its body, the surrounding tissue decays, and its body eventually disintegrates, causing the animal to perish. Although it is understood that the syndrome of loss of marine stars is caused by a viral pathogendensovirus associated with the starfish"), it was not clear what caused the outbreak of the disease in the first place.And although many species of starfish have begun to recover, the charismatic populations of the sunflower star – which can grow up to 3 feet in diameter – A new study suggests that ocean warming is probably to blame for its continued absence from the Pacific coast.

"The numbers of the starfish have remained so low in the last three years, we consider them threatened in the southern part of their reach, and we have no data for northern Alaska,"says Dr. Drew Harvell, a professor at Cornell University and lead author of this study.

A purple ocher star (Pisaster ochraceus) suffering from the disease of wasting.Jacqueline Sones

In deep water habitats, the sunflower star has been at the forefront of the loss of starfish syndrome. Eleven years of data collected during diving in waters between southern California and Alaska showed that sun-flowered stars were abundant before 2013 and that their populations declined sharply after the onset of the wasting syndrome. Scientists also found that the ocean had warmed by almost 39°F within a period of four years at some locations within that range. But, the unequal nature of this warming made it challenging to link temperature increases to the outbreak of debilitating disease. However, Dr. Harvell and his colleagues were able to demonstrate that the population of the sunflower star recorded unusual heating patterns in the Pacific Ocean.

"It is important to remember that the disease is a normal part of marine and terrestrial ecosystems," warns Dr. Colleen Burge, who studies marine diseases, but was not involved in the study of the star of the sun.Many factors, including man-made change, can improve disease transmission in the ocean and on land. "

In recent years, the Pacific Ocean has experienced record temperatures and sea heat waves that are expected to become more common as climate change intensifies. A hot period in the 1980s caused a huge outbreak of stinky foot syndrome among abalone species and eventually led to black abalone becoming a threatened species of federal extinction. And there is evidence that climate change will also influence diseases in corals, mollusks, seagrass, fish and marine mammals.

"Of course none of this happens in a vacuum," says Dr. Burge, "Other factors caused by humans can cause disease or be a co-factor in disease transmission … in this rapidly warming era."


Source link