Paralytic shellfish poisoning could be 'underreported' cause of death for marine birds

Humans are not the only species vulnerable to the deadly effects of paralytic shellfish poisoning, commonly known as PSP. In a recently published study by the U.S. Geological Survey, the disease has been named as the cause of death for multiple Kittlitz's murrelet chicks -- a species of concern -- found dead on Alaska's Kodiak Island.

Scientists believe that these are not the first seabirds to die because of PSP. "The impact of PSP in marine bird populations may be more severe than previously recognized," the study says.

According to the study, similar cases are likely "underreported."

Valerie Shearn-Bochsler, a USGS diagnostic pathologist at the National Wildlife Health Center, said it is likely underreported because biologists don't test for it. She said it is possible that the Kittlitz's murrelet deaths are a rare occurrence but because the test is not typically run in seabird mortalities and it is a difficult test to run, she doesn't believe "people think about it."

Infared cameras placed by researchers recorded the nestlings consuming fish just hours before their death. The study said that at the time of death, the chicks were apparently healthy, weighing a normal weight and living in mild weather conditions.

After they were found dead, their bodies were collected, placed in an ethanol solution for preservation and sent to the USGS Wildlife Health Center in Wisconsin, where necropsies were performed.

Of the eight birds that could be tested for PSP, all but one tested positive.


Shearn-Bochsler said it is not unheard of for other species to feel the effects of PSP.

"It has been recorded in humpback whales along the New England coast," she said. "It is not terribly surprising that the birds that eat fish could be affected."

She added that the number of adult Kittlitz's murrelet deaths are "extremely difficult to track," as they spend most of their time at sea, making it difficult to collect and preserve their carcasses.

Kittlitz's murrelets are found from southeastern Alaska to the eastern coast of Russia.

Megan Edge

Megan Edge is a former reporter for Alaska Dispatch and Alaska Dispatch News.