Researchers ranch horseshoe crabs on Jekyll

About 40 horseshoe crabs are settling into their new home in a first of its kind "ranch" on Jekyll Island. It's the brainchild of North Carolina-based biotech company Kepley Biosystems.

Kepley is looking to transform a decades-old industry that uses horseshoe crab blood to test the sterility of pharmaceuticals and medical devices. The crabs are typically caught in the wild, taken to labs, bled, then returned to the ocean, often worse for the wear. About a quarter of them die. But their numbers are declining. The fact that some shorebirds rely on horseshoe crab eggs to fuel their long-distance migrations adds to researchers' desire to take the pressure off wild populations.

Researchers at the University of Georgia Marine Extension and Georgia Sea Grant caught the 40 crabs in and around Jekyll. Then Kepley's Kristen Dellinger put them through a battery of blood tests earlier this month to get baseline statistics on their health. Afterwards, the project partners set them up in cages made of PVC pipe and crab trap netting in the saltwater Tidelands pond, an impoundment built as a yacht basin and later used as a water skiing venue. The 23-acre pond is linked to tidal creeks only by culverts that allow a flow of saltwater and its array of marine life.

After the crabs acclimate to the pond, Dellinger will return in a month or so for another round of tests and to implant ports to allow repeated, easy blood draws.

Attempts to raise horseshoe crabs in labs have proven less than ideal because in captivity their blood loses some of its most valuable components, said Dellinger, a research associate at The University of North Carolina at Greensboro, Joint School of Nanoscience and Nanoengineering, with which Kepley is affiliated.

Kepley researchers are betting that a semi-wild setting with supplemental food to keep them healthy and implanted ports will be the formula that proves profitable for the company and protective for the species. They eat marine worms, small clams and crustaceans in the wild. While awaiting their transfer to the ranch, researchers fed them scallops and shrimp supplemented with vitamins and minerals.

"They eat better than I do," Dellinger joked.

Researchers will continue to supplement their diets in the pond.

Commercial labs that process horseshoe crab blood, like Charles River Laboratories in Charleston, can remove up to a third of the animal's blood at a time. Kepley plans to reduce that stress on the animals by using a process similar to plasma donation in humans that removes the desired blood component and returns the rest to the animal.

"Ideally we'd like to bleed them more frequently but lower volumes so it's not so tremendous an impact on the animal, said Anthony Dellinger, Kristen's husband and president and scientist at Kepley BioSystems Inc.