It is a warm spring day and the Manatee is swimming down the muddy river toward the sea. The recent spring rains have clouded the usually clear water with runoff. The tide is turned, making the boundary between the river and the sea even more turbulent, with visibility only a matter of a few feet the Manatee swims along with the current its massive rear fluke driving it toward the oncoming defile between the sea and the river, the water is already brackish but is not yet fully salt water.
Suddenly there is a massive thump on the Manatees side, in panic it dives toward the bottom only to be smashed again and again by the rush of an unseen predator. The Manatee, mortally wounded, the brackish water stinging and burning in its horrible wounds, now only drifting, it bounces and rolls along the bottom of the river. The sharks, now visible in the less turgid water below the halocline, dine on the huge mammal, tearing off sections of its sides, back and belly with their sharp teeth as it dies.
The scene I have described occurred not recently, but around 30,000,000 years ago in the area now known as Alhambra Beach, Florida, just below Venice Beach. How do I know? I am holding a fossilized section of Manatee rib with the clear marks of a sharks teeth scoring one side. Now perhaps the Manatee died of natural causes and then was eaten, or the attack occurred in the Winter as the Manatee made its way into the safety of the prehistoric river towards the warm springs that gushed forth inland, creating the river, but needless to say, it was just as brutally consumed whether it began the ordeal as a living, breathing animal or as flotsam making its way to the Gulf. The remaining bones (either released during the feeding frenzy or after passing through the digestive system of a shark) ended up on the bottom of the river, were buried in the silt and became fossilized over the millions of years it took for me to find them.
Literally thousands of fossils are removed from the area off shore from Venice Beach each year, but storms and the erosion of the old riverbed by tides keep uncovering countless more. Some experts say that the area, right where a river met the sea, was a huge feeding ground for sharks and other marine predators. I get the feeling, based on the huge number of sharks teeth found, that it was also a shark breeding ground. You see when sharks mate the male seizes the female by the pectoral fin and in the throes of passion loses dozens of teeth. In pictures taken during the mating of sand sharks in the pacific the teeth fall like snow, covering the ocean floor.
Littering the bottom of the Gulf floor all along the area about 100 yards to over a mile offshore off of Venice and Alhambra Beaches is the bed of a prehistoric river literally covered with fossils of various animals. From the teeth of sharks (from tiny little ones barely a half inch long to the 1-6 inch long Megaladon teeth) to the bones of Mastodons and the delicate ear bones of prehistoric whales and porpoise just about any fossil can be found there. Divers come from all over the country to search for megs and the teeth of Mastodons in this, and other fossil bearing areas of Florida.
I found the Manatee rib in about 20 feet of water about 100 yards off of the Alhambra Beach shore, along with about 2 dozen sharks teeth and one large 14 inch by 5 inch fossil that appears to be a piece of a Mastodon skull but I am waiting to get feedback from some experts before I label it as such. This isn’t the first time I have dived Alhambra and won’t be the last. All-in-all I have pulled dozens of sharks teeth including a 2 inch fragment of a meg and a 1½ inch specimen from a Great White as well as many fossilized stingray barbs and miscellaneous bone fragments.
I have yet to see any of the modern day descendents of the Manatee killers during my dives although I am usually accompanied by a few grunts that love to pounce on anything I stir up when I search the bottom for fossils. You also see the occasional flounder and grouper as well. During my dives last year I also saw some gurnards. Gurnards are probably one of the oddest looking fish you will see. The Flying Gurnard has over developed pectorial fins that make it look like it has wings, under its mouth are tiny legs which it uses to pull itself along the bottom. This year I did not see and of the Gurnards.
What makes the diving at Venice Beach and Alhambra Beach areas so attractive is that the depth is only about 20 feet which means a single Aluminum 80 CF tank of air will last well past an hour, my double AL80 tanks will last 2 or more. That gives you plenty of time to traverse the 100 or so yards out to the closest edge of the fossil beds and search for whatever strikes your fancy. In addition there is usually reasonable visibility of up to 20-30 feet or more and usually little or no surf issues. Combine all of this with the usual Florida great weather and it makes for a very enjoyable day of easy diving.