Biofluorescence is essentially the ability of an organism, to absorb electromagnetic wavelengths from the visible light spectrum by fluorescent compounds, and the subsequent emission of this at a lower energy level.
What does Hannibal Lecter, Ernest Hemmingway and I have in common? A taste for fava beans and a nice Chianti? (Chianti – yes), renowned literary skill? (pah! If only!). The answer is in fact the islands of Bimini, Bahamas situated 50 miles off the coast of Florida, North & South Bimini are the smallest habitable islands in the Bahamas with a total area of 9-square-miles and just over 2000 inhabitants.
Hemmingway began visiting the islands in 1935 and spent time fishing and writing, whilst angling he garnered knowledge which contributed to the creation of Old Man and the Sea and Islands in the Stream. An Atlantic Blue Marlin caught off Bimini weighing in at 500lbs was allegedly the inspiration behind these novels.
The final scene of Silence of the Lambs see’s Dr Lecter calling Agent Starling from a payphone on a tropical island, that island being North Bimini.
So what is it about Bimini that resulted in my visit, or to be more precise – my return visit? I had first gone to Bimini when I was conducting research for my PhD in 2006, I was staying at the Bimini Biological field Station (Shark-Lab) founded by “Doc” Gruber and was tracking juvenile Lemon Sharks and investigating their depth utilization.
Bimini is a well known Lemon Shark nursery area first recorded by Doc in the 1980’s, however in addition to the Lemon Sharks the Bimini Islands are a marine biologists and even more so a shark biologists dream, in shallow, clear waters you can see Nurse, Blacknose, Blacktip, Caribbean Reef, Tiger & Bull Sharks as well as Rays, Sawfish and the reason for my trip this time, the Great Hammerhead (Sphyrna mokarran).
There has been talk of Great Hammerheads visiting the waters around Bimini from January through to March for decades, and long is the legend of South Bimini Islands “Harbour Master” a huge Hammerhead patrolling the docks for fishermen’s scraps. However it has only been the last few years that the area has emerged into the main stream and has become recognised as the place to dive with aggregations of Great Hammerheads.
I was there with Dr Craig O’Connell founder of O’Seas Conservation foundation and his team (Guido Leurs founder of Oceaware, Marcella Uchoa and Rachel Jacobson), I had first met Craig on my initial visit to Bimini and having kept in touch and collaborated on a research paper together it was a fitting place to catch up in person! We has rented a boat and were observing and photographing animals in situ by freediving and SCUBA diving.
Put simply, my dives with the Hammerheads blew me away!! Once the bait had gone in the water we were inundated with nurse sharks typically after only a couple of minutes, on average we only had to wait around 20 minutes until the unmistakable outline and approach of the Hammers were spotted from the boat, a speedy kitting up and grabbing of camera equipment ensued (with a quick nod to the O’ring gods) and we descended down to the white sand with depths around 6m. Seeing these animals up close in the water was incredible, I certainly don’t possess the vocabulary or the literary skill to do them justice, they are truly humbling and awesome.
On each dive Hammers exhibited different behaviours and swimming patterns which allowed for some fantastic photography opportunities , unlike the more classic shark body shape the angles and form of the Great Hammerheads combined with the sunlight filtering through the water and the approach of the sharks created the potential for yet another different and interesting shot, the opportunities were endless!
Sphyrna mokarran is the largest species of hammerhead shark, capable of attaining a total length of just over 6m (20ft) with 4m being a more usual maximum length. They are unmistakable with the straightness of the front margin of their head combined with their enormous sickle shaped first dorsal fin, they are a coastal pelagic and semi-oceanic species, considered to be an opportunistic predator feeding on a variety of prey including; stingrays and other batoids, small shark species, groupers, toadfish, jacks, crabs and squid etc. Males reach maturity around 2.5m and females around 3m, females breed every 2 years and have an 11 month gestation period (they are viviparous – pups nourished with a yolk sac placenta), litter size ranges from 6-42.
S. mokarran is classified as endangered by the IUCN Red List with a declining population trend, animals are taken as by-catch and as a target species in longline, fixed bottom net, hook & line, and pelagic and bottom trawl fisheries. Their fins are highly prized for shark-fin soup. These fishing pressures coupled with the Great hammerheads size at maturity and low fecundity make it extremely vulnerable, global population declines range from 79-90% in the last 25 years. In 2014 S. mokarran was listed on CITES Appendix II, which includes a list of species that are not necessarily now threatened with extinction but that may become so unless trade is closely controlled. International trade in specimens of Appendix II species may be authorized by the granting of an export permit or re-export certificate. No import permit is necessary for these species under CITES (although a permit is needed in some countries that have taken stricter measures than CITES requires). Permits or certificates should only be granted if the relevant authorities are satisfied that certain conditions are met, above all that trade will not be detrimental to the survival of the species in the wild.
On the subject of protection I worry about the future of Bimini and its marine wildlife, since I first visited the island 9 years a lot has changed. A Malaysian consortium (work originally began by “Bimini Bay Resort” but is now “Resorts World Bimini”) was granted approval to build a resort, casino, marina complex designed to attract 500,000 tourists a year, as a result mangrove habitats have been destroyed (essential shark nursery areas) and dredging of channels for cruise ships has taken place with the resulting repercussions on the coral reefs and critical habitats for other species such as lobster, grouper, and conch not to mention the natural storm protection for the island itself.
Bimini is a place with the power to turn dreams into a reality, my sincere hope is that people in positions of power will recognise the true beauty of Bimini and conserve it so that these Islands will never be referred to in the past tense, as a paradise lost….