Cone Snails' Role In Medicine Could Threaten Them With Extinction
December 24, 2013

Cone Snails’ Role In Medicine Could Threaten Them With Extinction

Brett Smith for - Your Universe Online

Valued for millennia for their decorative shells, marine cone snails are now grabbing the interest of pharmacologists who believe the snails’ powerful venom could eventually be used to formulate equally powerful drugs to treat a range of illnesses.

Unfortunately, many species of cone snails are currently threatened and their plight has been largely ignored, according to a new report in the open access journal PLOS ONE.

In the study, the researchers conducted a global assessment of all 632 species of cone snails for the International Union for Conservation of Nature (IUCN) Red List. The first assessment for any group of marine snails revealed that some species are at risk of extinction. The study authors said they found clusters of snail species living in small areas that could rapidly disappear if the threats against them increase.

"Cone snails are seeing rapid shrinkage of their habitats as human impacts multiply,” explained Howard Peters, an environmentalist at the University of York in the UK. “We found that 67 species are currently threatened or near-threatened with extinction worldwide, but this rises to nearly half of all species (42) in the Eastern Atlantic, where there is an extraordinary concentration of range-restricted species.”

“In Cape Verde, 53 species are found nowhere else in the world of which 43 live only around single islands,” Peters said. “Here, pollution and shoreline construction for the expanding tourist industry threaten their existence. Sand is being dredged from the shallows where cone snails live to make concrete for resorts, harbors and cruise liner terminals. Collection of shells by divers and snorkelers could hasten their demise."

The snails’ ornate shells are highly coveted and have been collected for thousands of years. Some shells have even been found in ancient Neolithic sites. A few rare shells have been known to sell for thousands of dollars – a collecting phenomenon that ironically threatens to wipe out some species.

Study researchers said they found a significant lack of protection for many cone snail species.

"Despite their extraordinary beauty and value, cone snails have fallen completely underneath the conservation radar,” Peters said. “These snails need swift action to protect their habitats and publicize the dire consequences of irresponsible shell collecting of the most threatened species. Holidaymakers need to think twice before taking a seashell home as a souvenir."

Study author Callum Roberts noted that the forces of climate change also have the potential to wipe out cone snail species.

"This study provides an important yardstick from which to measure our growing impact on mollusks, one of the richest groups in the sea, and the long-term consequences of ocean acidification,” said Roberts, a marine conservation biologist at the University of York. “Ocean acidity is increasing due to fossil fuel burning as carbon dioxide dissolves in the sea. Without action to reduce emissions, rising acidity could cause shelled marine creatures to literally dissolve away by the end of this century."

While some may covet cone snail shells, drug makers see the snails as having an entirely different value. Many of these mollusks secrete strong venom that immobilizes fish, worms and other prey. These neurotoxins are said to have potential in the development of life-saving drugs.