Scuba Diving Beyond the Reef
Intentionally or not, all divers have occasionally found themselves drifting over sand. Maybe it was while you were navigating between wrecks on the Wreck Trek or when you wanted to work on your underwater photography skills at Blue Heron Bridge.
It might even have been that time you just flat out wandered off course and missed the reef. Fear not! The seafloor is rarely barren sand, and as any diver lucky enough to encounter a sawfish knows, going beyond the reef may turn out to be one of the best dives of your life!
Speaking of Sawfish
Trust us when we say you’ll know a sawfish if you see one. The clue to its name is its long narrow snout that’s edged with 24 or more pointed teeth—on each side. A sawfish typically attains 6-12 feet in length.
Two dorsal fins give it the appearance of a shark, but it belongs to the ray family. In fact, rays may be the largest of the marine animals you encounter over sandy or rubble-strewn bottoms.
Rays can be identified by their large pectoral fins that resemble wings. Watching them “fly” through the water column is a breathtaking experience.
With the exception of eagle and manta rays, the ray families in our area are bottom dwellers and are often seen skimming the seafloor, then settling into the sand to feed and avoid predators. From above, you may detect their diamond outline in the sand. As you get closer, look for its eyes and respirator openings.
If startled, it will emerge from the seafloor, find a new spot to settle onto, and then use its pectoral fins to flick sand until its camouflaged once again. They feed opportunistically, however, shrimp, crabs and small fishes make up its preferred diet.
The most common ray in our area is the southern stingray. Variously brown, gray, and black, they attain 3-6 feet and can often be found with a yellow jack or bar jack riding shotgun slightly above them. The yellow stingray is less common and smaller—less than a foot—and is covered with numerous pale and dark spots on its yellowish brown skin.
Spotted eagle rays are more skittish, and while they often cruise out of sight and higher in the water column, they occasionally stop to dig in the sand for mollusks. You can identify these 4-6 feet rays by their dark backs and numerous white spots.
Smaller but still somewhat easy to see
Most bottom dwellers are masters of disguise. Even though they may be larger than many common reef dwellers, it still takes a sharp eye to see them. Peacock flounder with its blue rosettes and fringe-like edges can dramatically change its color to match its surroundings. Batfish have pectoral and ventral fins that they use to “walk” on the ocean floor. Scorpionfish hide in plain sight thanks to their fleshy appendages, mottled earth-tone skin, and their tendency to remain still. Stargazers can bury themselves in the sand by rapidly vibrating their bodies. Chances are, you’ll only see their two eyes gazing upward—which is how they got their name.
Just because you don’t see it, doesn’t mean it isn’t there
Most of the critters that call the sand home take a bit more effort to find. Best advice? Slow down and watch your buoyancy. In the fish identification books, there is a whole host of small, elongated bottom-dwelling fishes that include gobies, blennies, and jawfishes.
While a few species drift just above the bottom, most live in holes and dens on the bottom. Oftentimes, divers catch just a glimpse of their heads. Startle them, and it will take patience and good buoyancy control before they reemerge from their holes.
What to look for? Think small. None of these fishes exceed three inches, and gobies and blennies are particularly easy to confuse. The key difference is their respective dorsal fins: gobies have two; blennies often have only one long one. While gobies can be very colorful—especially further afield in the Caribbean—the species common to Florida tend to be more muted, with skin tones that blend with their sandy environment.
Another identification clue is that most blennies have bristle-like protrusions called cirri above their eyes. In contrast, jawfish have proportionally large mouths and gaping jaws. Male jawfishes are responsible for incubating the eggs, which they do in their mouths.
About those rocks…
Sand is rarely just sand. If there are rocks, there is almost always something sheltered in the crevice of the stone or under its small ledges.
This is where you most likely see small crustaceans like the spindly yellowline arrow crab with its purple-tipped legs or decorator crabs that affix various bits of shell and debris to themselves to change their appearance.
When the sun goes down
Many marine animals that shelter on the reef during the day, leave it to hunt at night.
Florida’s spiny lobsters are nocturnal and when the sun goes down, they abandon their cubby holes and are commonly found walking across the open sand as they search for crabs, shellfish, and fishes to eat.
Sea urchins, too, often head to the nearby sea floor to feed on algae.
The best place to play in the sand
Hands down, Blue Heron Bridge at Phil Foster Park. Don’t believe us? PADI’s Sport Diver magazine once named it the best dive site in the world! This is a tide-dependent shore dive, and the shallow water means plenty of bottom time to explore the considerable diversity of marine life that isn’t commonly found elsewhere.
Look for spotfin, yellowhead, and banded jawfish—extra credit if you spot one with eggs in its mouth. Here, too, you can find plenty of blennies.
Then there are the striated frogfishes, which look a lot like it donned a hairy ghillie suit as camouflage. If you see what appears to be a covered hole in the sand, it may belong to an octopus.
While their habitats include seagrass beds and coral reefs, they also create dens in sandy plains and conceal the opening with debris. Oh, and while they aren’t bottom-dwellers, look for the seahorses under the bridge.
Don’t forget to look up!
I know, this is an article on what’s in the sand, but you never want to lose your situational awareness while diving. Plus, it’s sea turtle season, and they often leave the reefs to move shallower into the seagrass.
Besides, your best chance to see a leatherback sea turtle is to catch one on the surface while migrating to its nesting beach (most of their time is spent well below recreational diving limits).
Finally, time’s running out to see our migrating lemon sharks! They’re easy to distinguish by the yellow-brown hue of their skin, and a mature lemon typically measures in at 10.5 feet.
They’re easy to distinguish by the yellow-brown hue of their skin, and a mature lemon typically measures in at 10.5 feet. They feed on bony fishes, crustaceans, mollusks, and rays, and like all sharks, they frequently lose their teeth—one more thing to look for when you’re combing the sand!
Whether you want to explore a reef, wreck, or Blue Heron Bridge, Jupiter Dive Center has the perfect dive for you. Call us at 561-745-7807 or book your dive online—because no matter where you end up, it’s always a great day to go diving!