Whales, Turtles and Other Wildlife with Cancer

Not too long ago it was in the news that Tasmanian devils have a form of contagious skin cancer working it’s way around. In this story it talks about more water creatures, turtles whales, etc. that are developing cancerous tumors. Studies are being conducted to perhaps find the virus that is suspected for causing some of the cancerous tumors, and it appears that polluted water ways are of no help either, but we probably already knew that. BD

Tasmanian devils threatened by contagious skin cancer

A newly published paper in the July edition of Nature Reviews Cancer compiles information on cancer in wildlife and suggests that cancer poses a conservation threat to certain species. The WCS authors highlight the critical need to protect both animals and people through increased health monitoring.

"Cancer is one of the leading health concerns for humans, accounting for more than 10 percent of human deaths," said Dr. Denise McAloose, lead author and Chief Pathologist for WCS's Global Health program. "But we now understand that cancer can kill wild animals at similar rates."

Many species living within polluted aquatic environments suffer high rates of cancerous tumors, and studies strongly suggest links between wildlife cancers and human pollutants. For example, the study cites the case of beluga whales in the St. Lawrence River system. These whales have an extraordinarily high rate of intestinal cancer, which is their second leading cause of death. One type of pollutant in these waters—polycyclic aromatic hydrocarbons (or PAHs)—is a well-known carcinogen in humans, and PAHs are suspected carcinogens for beluga whales as well. Fish in other industrialized waterways, including brown bullhead catfish and English sole, also exhibit high levels of cancer.Other virus-induced cancers can affect the feeding ability or eyesight of wildlife. Green sea turtles—a migratory species in oceans across the globe—suffer from fibropapillomatosis, a disease that causes skin and internal organ tumors. A virus is suspected as the cause these tumors, and environmental factors such as human-manufactured carcinogens might exacerbate their severity or prevalence.