Seton Hall Researchers Produce Shark Repellent

In his research to develop effective shark repellent, Eric Stroud has found that what works best are the rotten carcasses of other sharks, which had long been part of fishermen's folklore.

"It's the most god-awful thing you ever smelled," said Stroud, 35, a Ph.D. student in chemistry at Seton Hall. Stroud started his company, SharkDefense, to develop repellent technologies in 2004, three years before he began his doctoral studies. The main consumers of his products are fishermen, hoping to ward off sharks and prevent them from being ensnared in the lines. SharkDefense has a $20-$25 can of shark-repelling aerosol spray available, but it also has repellents in the forms of magnets and metals.

The idea to design shark repellent came to Stroud in the summer of 2001, which he remembers as "the summer of the shark," since the media seemed overloaded with reports of even minor contacts between humans and sharks. He had been working as a pharmaceutical consultant and personally funded his initial research, setting up tanks in his Sussex County home and importing young sharks from the Florida Keys to test repellents on.

Though he learned relatively early on that liquefied rotten shark matter worked as a repellent, he began his doctoral studies at Seton Hall in 2007 to learn what properties of the material had this effect, and how the compounds could be isolated. He was attracted to Seton Hall because of its recently renovated science building, McNulty Hall, and state-of-the-art equipment.

In one of his first classes, he studied with Dr. James Hanson, who became his advisor and a collaborator on the shark repellent research. They recently won a one-year $100,000 grant from the National Oceanic and Atmospheric Administration, to be shared for research purposes by partners including SharkDefense, Seton Hall and educational institutions based in Florida and the Bahamas.

Their goal is to develop technologies that reduce by-catch, the species accidentally caught by fishermen for which they have no use. Hanson and Stroud are hoping to develop a repellent gel that could be coated on baits and would be released more slowly when immersed in water.

Dead shark matter seems to work as a repellent by triggering a survival instinct in sharks, alerting them to the possibility that the waters they're swimming through are unsafe.

Ironically, the end goal of their research has become more focused on protecting sharks from humans, instead of the other way around. Hanson points out that there are only about 35 to 80 shark attacks worldwide per year. "The difference is, the fishing industry probably catches some enormous number of sharks per month," said Hanson.