If you ever find yourself on the relatively isolated south island of the Biminis, you may come upon a strange group of bare-footed, tanned young people fixing nets and willing to talk for hours on end about sharks. These are the volunteers of the Bimini Biological Field Station (BBFS) aka Sharklab. The BBFS was established in 1990 by Dr. Samuel Gruber to study the marine ecosystems of the Bahamas with a focus on the many species of sharks and rays found in the surrounding waters. Since its inception, the Sharklab has been host to several principal investigators working on their doctorates, rotating teams of dedicated staff members, literally thousands of students and volunteers, dozens of film and news crews, and many other guest researchers. Volunteers come from all over the world to gain hands-on field experience with sharks. Over the last two decades, many insights into the biology and ecology of sharks have been discovered by the team of researchers working at the BBFS.
Much of this research has focused on the lemon shark (Negaprion brevirostris) an ecologically important large coastal species in the tropical, marine ecosystem. The lemon shark uses areas around Bimini’s lush mangrove systems as nursery grounds. Every April and May, pregnant females arrive in Bimini to give birth. These sharks exhibit a biennial reproductive cycle meaning individual sharks give birth every other year. Most females are also philopatric, which means that the same shark will return to Bimini to give birth over and over again. Each reproductive cycle, a lemon shark mother will give birth to an average of ten pups approximately two feet long. These juvenile sharks will remain in their primary nursery near the mangroves for the first three to five years of life.
The lemon shark youngsters are the focus of a majority of the research at the Sharklab. Over the past 20 years, the BBFS research team has conducted studies on population dynamics, genetics, age and growth, diet, habitat selection, movements, and social behavior of these sharks. The current major study, led by University of Miami doctoral student Kristine Stump, is investigating the effects of nursery habitat loss on juvenile lemon sharks, with the goal of developing sound management strategies. The research team also studies many other species of sharks and rays around Bimini and perform monthly surveys with long-line fishing gear both on the shallow banks and adjacent deep drop-off to monitor the shark populations around the islands. Over the course of this work, the research team has captured 15 different species of sharks showing the abundant diversity of species around Bimini. Recently Sharklab researchers have collaborated with scientists from the Guy Harvey Research Institute on a project using satellite tags to monitor movements of large tiger sharks. Discovering new facts about sharks inevitably leads to new questions so the staff and volunteers at the Sharklab will continue to be out there fixing nets, fighting mosquitoes, avoiding sunburn, and conducting the research needed to better understand the biology of these ancient lords of time—the sharks. For more information, visit http://www.miami.edu/sharklab.
Story by: Bryan Frans, Ph.D.
Bimini Biological Field Station