Anita had been leading a dive in the Bahamas at a site called the 'Sea Garden', when she discovered the carcass of a green sea turtle with a hook protruding from its decomposing tongue.
Images like this can become warnings for the future. Shane Gross
The animal had obviously been trapped in situ for a significant period of time, and had drowned.
Standing on the swim step, trying to time my entry with a gap in the dozen or more lemon sharks circling directly below me was a bit daunting the first go around. Of course, the sharks knew this routine well and skillfully avoided my clumsy splash into the water. The reward waiting beneath the surface was an assemblage of sharks that cannot be collectively encountered anywhere else in the world.
Like a fashion model up on the catwalk, great hammerhead sharks sashay into one’s field of vision, and, if they were human, you would probably say they have just “made an entrance”. Their strange mallet-like head, robust body girth and tall sickle-shaped dorsal fin make them well-nigh instantly recognisable, and most other sharks in the immediate area spot that too and give them a wide berth.
A fifty-minute flight southeast from the bustle, cruise ships and tourist-centric Nassau, lies the sleepy island of San Salvador. Twelve miles long and five miles wide, she is the tip of an underwater mountain rising from 5,000 metres below (15,000 feet) surrounded by picture-postcard, crystal-clear, blue seas.
First described in 1837 by the German naturalist Eduard Rüppell, the great hammerhead shark (Sphyrna mokarran) is the largest of the hammerhead shark family and can reach a length of over 6m (20ft), although some specimens have been seen to be much larger than this. However, with overfishing, the great hammerhead is usually observed to be much smaller than this.
"We found that newborn sharks captured in the mid-1990s left the safety of the islands when they were between five and eight years old," explained Dr Kevin Feldheim, the A. Watson Armour III Manager of the Pritzker Laboratory for Molecular Systematics and Evolution at The Field Museum and the lead author of the study.