A spinner shark swims just offshore on Midtown Beach in Palm Beach on Tuesday. (Photo by Jeffrey Langlois/Palm Beach Daily News)

“No swimming” flags fly at Midtown Beach on Friday as sharks move through the area. (Photo by Lannis Waters/Palm Beach Daily News)

Bait hangs on a hook as researchers fish for sharks in Palm Beach. (Photo by Lannis Waters/Palm Beach Daily News)

Josh Jorgensen, Founder and Director of the Blacktip Challenge Shark Fishing Tournament, casts for sharks on Midtown Beach. (Photo by Lannis Waters/Palm Beach Daily News)

Josh Jorgensen hauls ashore a blacktip shark. (Photo by Lannis Waters/Palm Beach Daily News)

Attaching a rope to its tail, Jorgensen pulls the shark up onto the beach where researchers can work on it. (Photo by Lannis Waters/The Palm Beach Post)

As beachgoers watch and take photos, Jorgensen hauls the shark ashore. Jorgensen is working with researchers from Nova Southeasten University and St. Mary's Hospital to collect and analyze bacteria from sharks' mouths to help improve the selection of antibiotics used for victims of shark bite victims. They have caught 19 sharks so far, including the two 6-foot backtips they caught Friday, and hope to collect 50 for the project, including some from the Bahamas to get more species. (Photo by Lannis Waters/Palm Beach Daily News)

Researchers remove the hook from the shark's mouth. (Photo by Lannis Waters/Palm Beach Daily News)

Jorgensen and Nathan Unger, an assistant professor at Nova Southeastern University, measure the blacktip shark. (Photo by Lannis Waters/Palm Beach Daily News)

Surrounded by a crowd of curious beachgoers, Tom Kieras, a shark fisherman from Jupiter who works to spread information about sharks and protect them, holds down a blacktip while Jorgensen and Unger prepare to take samples. (Photo by Lannis Waters/Palm Beach Daily News)

Jorgensen pries open the shark's mouth. (Photo by Lannis Waters/Palm Beach Daily News)

Samples are taken from the shark's mouth so the bacteria can be analyzed to help improve the selection of antibiotics used for shark bite victims. (Photo by Lannis Waters/Palm Beach Daily News)

The swabs taken from the shark will be analyzed to determine the types of bacteria present. “We want to optimize antibiotic therapy for our patients (and) reduce consequential adverse effects by using less antibiotics”, says Unger. According to Dr. Robert Borrego, trauma director at St. Mary's Medical Center, “The problem that develops from a surgical standpoint is when patients get bitten and they develop infections, they require more surgery, and when the tissue gets infected, if it doesn't respond to the antibiotics, then the only therapy left is to remove the tissue”. (Photo by Lannis Waters/Palm Beach Daily News)

Jorgensen drags the shark back to the water after samples were taken. (Photo by Lannis Waters/Palm Beach Daily News)

Jorgensen gets ready to release the shark. (Photo by Lannis Waters/Palm Beach Daily News)