Diving the Rainbow River (near Ocala, FL)

[digit]

Last weekend TFF member calhounensis (Daniel) posted a notice that he was driving down from Ohio for the Florida Paleontological Society meeting & fieldtrip on Saturday in Bradenton (his old hometown). He wanted to know if anybody was up for some diving off Venice to fossil hunt. It has been years since I've taken the opportunity to do so (been focusing more on the Peace River lately) and so I said I was interested. As plans evolved it turned out that windy weather (and unseasonable storms) had been wreaking havoc with the offshore visibility and diving off Venice would likely not be in great conditions. Daniel came up with alternative which was to dive the Rainbow River in Dunnellon, FL instead. This was even more intriguing as I've never done that before and I'm all about new experiences. My wife Tammy was able to take off work Friday and so Thursday evening after she got home from work I had a whole array of gear ready to pack into the car for the trip north--scuba tank & gear, wetsuits (cold water those spring-fed rivers), sifting gear (screen & shovel), and even the "Aqua-Scope" we'd picked up at the silent auction table at the Florida Paleontological Society (FPS) meeting last fall. The scope is basically a portable glass bottom boat in that it is a rectangular "cone" of Styrofoam with a pane of glass about the size of a piece of paper at the bottom. Two rope handles and curved edges at the top to fit your face and forehead complete the high-tech design. Tammy thought it would be fun to try this out on the Peace River and so we bid and won the auction item. Needless to say it hasn't seen action on the Peace River yet this season and so the Rainbow River would be its first chance to be used.

Once I realized how far north the Rainbow River was I decided to book a hotel in Ocala. Rather than going up for a single night--a 5.5 hour drive (each way) for a single dive seemed a bit excessive--we booked a 3-day weekend in Ocala and joined Dr. Hulbert from the Florida Museum of Natural History (FLMNH) for two more days of digging in the new Montbrook site. You can read about that weekend here:

http://www.thefossilforum.com/index.php?/topic/63056-volunteer-dig-with-the-flmnh/?p=673017

We met up with Daniel early Friday morning and followed him to K P Hole Park on the river where we could rent a canoe (for us) and a kayak (for Daniel). We decided to paddle upstream a ways and then work our way downstream to the exit point on SW County Hwy 484 (just past the colorful Swampy's Bar & Grille restaurant) where we could call for a pickup that would take us back to the park and our cars. With everything loaded on our rented means of flotation we took off upstream. The water was so much clearer than the tea colored tannic waters of the Peace River being spring fed. We could see a wide variety of fishes in the gin clear water and an amazingly high density of turtles--gators (thankfully) seemed not to be in residence. We arrived at our first spot to get in and get wet. I donned my thickest neoprene (a 5mm suit) and an additional hooded vest (most of your heat is lost through your head and so a hood will go a long way to retaining body heat. As the river is spring fed from underground taps into the karstic groundwater supply the river maintains a relatively constant temperature of around 72 F (around 22 C). A fine temperature for floating down the river on an inner tube on a hot summer day but quite chilly when immersed for extended periods on scuba. I was used to diving in 55 F water when I lived in the Chicago area (and even two very silly ice dives at a temperature of around 37 F) but since moving to Florida two decades ago my skin has thinned and I am now a proud card-carrying member of the Warm Water Wimps and cringe at temps below 80 (unless there is a good reason to dive).

I was wet most of the day and (uncharacteristically) didn't grab the camera to take my usual number of photos to illustrate the day. My wife (who was smarter than me and decided to stay warm an dry in the canoe) was enjoying the beautiful surroundings and plentiful wildlife but didn't think about snapping any other photos than this one as I first entered the chilly water.

[digit]

I had fun learning the techniques of fossil hunting in this river following Daniel's lead. He had showed us some gorgeous mammal material that he had pulled from this river on previous dives and I was eager to see what I might be able to find. Quickly, I realized this was going to be more challenging than I thought. After using rapid movements of your hands to send pulses of water at the bottom to remove the top layer of soft mud and algae you can quickly see the chunky composition of the river bottom. It is made up of small broken pieces of limestone (and likely phosphate) that can be stained black or brownish making it difficult to distinguish from bone fragments at first. I had my search image set on the potential of some larger finds--a complete mastodon tooth or dire wolf mandible with teeth in place must surely be waiting for me under the next chunk of rock.

While I fanned and searched Daniel swam over and showed me some nice shark teeth and garfish ganoid scales that he had found. I had yet to find similar and considered that I probably wasn't focusing on smaller items like shark teeth and scales while looking for larger items like tapir, horse, or camel teeth. All I found were a few small bone chips which I brought back to Tammy just to prove that I wasn't entirely blind. Actually, I realized that I really do need diopters in my mask to help with close-up vision underwater. We tried another spot further upstream where Daniel continued to find some small items while I was skunked. I didn't really mind though as the area we were diving was really fascinating. At one spot the amount of freshwater jetting up through a crack in the limestone caprock was causing the overlying sand to bubble and boil. Like quicksand the sand in this area was more water than sand and you could plunge your hand into the sand with no resistance at all--kinda fun and it takes your mind off the cold. We decided to reserve some air in our tanks for some spots downstream and came back up from the 6 meter (20 foot) depth at the bottom of the spring and saw a large crack going down into the karstic caverns below. It was pumping out quite a bit of water which curiously was actually warmer that the surrounding river water we were diving in.

We tossed our diving gear back on our canoe and kayak and paddled effortlessly downstream letting the current do most of the work. We saw a nice diversity of waterfowl including the highly colorful Wood Duck (Aix sponsa) which we don't seem to get further south in Florida where we usually bird watch. Daniel also spotted a group of River Otters (actually a "romp" of otters if you want to be precise). He said that otters are only occasionally spotted here and that it was a welcome sight. In over 20 years in Florida we'd only seen otters twice before so this foursome of otters was a treat. A little while later Tammy spotted another otter further down the river so we were having a great time on this picturesque river.

We pulled the watercraft over at a spot that Daniel had had some success at in the past and suggested we try again here. Once again I found an appropriate looking spot and began fanning to remove the top layer of algae and mud. The bottom which was composed of sand and chips of limestone rock could be easily excavated a few inches by more vigorous hand fanning--a good way to keep warm as well. I spotted a few little pieces of turtle shell here and there so at least I knew I was into some sort of vertebrate material (though not very dense). I then spotted a small piece (about the size of a fingernail) that flew up into the water as the result of my vigorous fanning which caught my eye. It was a layered combination of white and brown and I popped it into my (rather pathetically empty) plastic collection bag for later inspection above water. It was as I suspected a tiny fragment of a mastodon molar with unbelievably white enamel. I'd seen this coloration on some of the teeth Daniel had showed us that morning so I wasn't too surprised by the coloration. Because of the white coloration and the striations which are characteristic of mastodon enamel as well as the darker dentin material adjoining it I joked that this was a piece of fossilized coconut--which it surprisingly greatly resembles.

Daniel came over to me and tapped me on the shoulder. When I came up out of the water he said that I'd have to go see what Tammy had just found. We were in a shallow area and he had tried to do a little sifting with the screen we brought along. The material on the bottom was a lot harder to shovel up than the smoother rounder phosphate pebbles in the Peace River and quickly gave up on that idea. She had decided that she would give the Aqua-Scope a try and in just a few minutes had spotted the outline of something interesting under a thin layer of sediment mud. Blowing the mud off with a wave of her foot while viewing her actions through the scope she saw a bone emerge. When I made my way over to where Tammy was I could see it was an interesting bone. Daniel figured it for a toe bone (metatarsal) either from a big cat or possibly bear. With all of our expensive dive gear and effort the best find of the day went to Tammy with her $10 glass and Styrofoam low-tech tool.

As we were planning on seeing Dr. Richard Hulbert from the FLMNH the next day at the Montbrook dig site, we brought along Tammy's find where he confirmed that (though the ends were a bit beat up) it was likely from a Jaguar (Panthera onca). Here's a close-up look at Tammy's jaguar bone and my measly few turtle shell fragments.

Though neither Daniel nor I found anything to write home about, Tammy was quite happy about her find. I joked that since she had gotten a jaguar that I should be allowed to get one too--preferably a Jaguar XKR-S Coupe model (with the 550hp supercharged 5.0 liter V8 engine) but I don't see that in my future. I'm just happy she continues to let me keep dragging her out on fossil hunting trips. Although the trip was (nearly) a bust in terms of fossils found it was a great new experience--which matters much more--and we got to meet-up with another TFF member while doing it.

Cheers.

-Ken

[jcbshark]

Nice write up Ken, and congrats on the jaguar material Tammy : )

[digit]

She got the best find on Friday (with the least effort) at Rainbow River on Friday and discovered the largest find (gomphothere atlas vertebra) in her square on Sunday at the Montbrook volunteer dig. I see I'm going to have to step up my game just to keep up. Daniel was surprised that we didn't hit more fossil material but from what Dr. Hulbert mentioned on Saturday the fossil layer exposed in the Rainbow River is not very thick and you've got to be in the right place to get into the good stuff (likely we were close with jaguar bits). I may pick a nice warm summer day soon and try again to see if I have any better luck but there are so many other possibilities for fossil hunting near and far that I have no immediate plans to dive in cold water again.

Cheers.

-Ken

[anthracite31]

Nice write up! Thanks for sharing.