Just when you thought it was safe to go back in the water…
Marcus Drymon of the Dauphin Island Sea Lab published “Distributions of Sharks across a Continental Shelf in the Northern Gulf of Mexico” (11 page PDF – pretty fascinating reading), which found that the most abundant taxa are the Atlantic Sharpnose Shark Rhizoprionodon terraenovae, Blacknose shark Carcharhinus acronotus, and Blacktip Shark C. limbatus. By my rough calculations based on their data, these three species accounted for more than 75% of the 22 species of sharks identified in the study.
DISL found that:
Blacknose sharks had the highest catch per unit effort (CPUE) in the middepth stratum (10–30 m), blacktip sharks had consistently higher CPUE in the shallow depth stratum (<10m), and Atlantic sharpnose sharks showed high abundance throughout both the shallow and middepth strata. Length frequency and sex ratio analyses suggest that Atlantic sharpnose and blacknose sharks are using waters greater than 30 m deep for parturition, whereas adult blacktip sharks are probably using shallow waters for parturition.
The Alabama Department of Conservation and Natural Resources provides these tips on Shark Safety:
Always stay in groups since sharks are more likely to attack a solitary individual.
Do not wander too far from the shore — this isolates an individual and additionally places one far away from assistance.
Avoid being in the water during darkness or twilight hours when sharks are most active and have a competitive sensory advantage.
Do not enter the water if bleeding from an open wound or if menstruating — a shark’s olfactory ability is quite acute.
Wearing shiny jewelry is discouraged because, to a shark, the reflected light resembles the sheen of fish scales.
Avoid waters with known effluents or sewage and those being used by sport or commercial fisherman, especially if there are signs of bait fishes or feeding activity. Diving seabirds are good indicators of such action.
Sightings of porpoises do not indicate the absence of sharks — both often eat the same food items.
Use extra caution when waters are murky and avoid uneven tanning and bright colored clothing — sharks see contrast particularly well.
Refrain from excess splashing and do not allow pets in the water because of their erratic movements.
Exercise caution when occupying the area between sandbars or near steep dropoffs — these are favorite hangouts for sharks.
Do not enter the water if sharks are known to be present and evacuate the water if sharks are seen while there. And, of course, do not harass a shark if you see one!
Piers and surf fishing attract sharks - why do we build piers and allow surf fishing in beach areas? Is there a better way to balance fishing and kids playing at the beach?