For this nature note...I thought it would be interesting to relate a story that happened to us a few weeks ago.
Paul Gravil and I were sitting in lawn chairs on the Spring Island boat ramp fishing. Paul had agreed to help me with some preliminary field work for a potential bonnethead shark study in Chechessee creek. We are interested in marking individuals to determine if the adult and juvenile sharks caught here exhibit a high degree of site fidelity (in other words do they come back to the same creeks and docks year after year). I realize that this description sounds suspiciously like fishing but hey, somebody has to collect the data.
It was a beautiful quiet evening with a nice cool breeze. The sun was dipping low in the sky giving the marsh banks a pleasant glow and turning the Spartina grass to a wonderful shade of green. Paul and I were sitting on the dock in lawn chairs facing the marsh eating leftover blue crabs that he and Lisa had prepared the night before. Dixie (the Gravil pooch) and Bill Allen's dog "DD" were also in attendance. We noticed a group of dolphins feeding in the mouth of the creek across from the dock. We could also hear the distinctive sounds of the dolphins splashing and breathing. Strand feeding on Spring Island is a pretty common occurrence but it is always a treat to see dolphins sliding up in shallow water and sweeping fish up on to the bank. The dogs got pretty excited about the spectacle and began to whine and pace up and down the dock. Fishing, good food, dogs, dolphins...now this is about as good as it gets!
I took a minute to change the bait on my hook and when I looked up, I noticed that the dolphins had moved much closer, swimming within 20 feet of the dock. One of the animals glanced up at us, did an extreme headfirst dive and disappeared under water. I assumed that the show was over and the dolphins had gone under the dock and up the creek. An instant later, a wall of water erupted up from the waterline and across the dock soaking Paul and narrowly missing me. Paul sprang to his feet just in time to see a dolphin fluke fling another twenty gallons of water across his chest and body. Talk about awesome! The splashing subsided and the dolphins disappeared leaving a wet dock and soaked Paul. For the record, neither me nor the dogs got a drop of water on us. Paul and I proceeded give each other high fives, recounting the adventure and laughing hysterically.
Weeks later, I am still not sure what caused that dolphin or dolphins to splash us. Maybe the dogs were actually the target and they leaped out of the way just in time. I guess there are a lot of possible explanations but I am convinced the dolphins accomplished exactly what they intended to do. I think they were playing with us, splashing water on Paul to see how we would react. Come to think of it, I am pretty sure that I heard the muffled, underwater sounds of dolphin chuckling right after it happened
Check out the video below of dolphins strand feeding off of Hilton Head.
As a kid, about this time of year, my friends and I would collect mistletoe to sell door to door in the neighborhood. To be honest, the selling part was not that interesting but the collecting – that was awesome! My favorite technique involved climbing high into the branches of a tree with a knife or small saw (usually held in your teeth to facilitate climbing), slicing off an appropriate bunch and dropping it down to the ground. My friends’ dad was horrified at this technique and deemed it far too dangerous for kids our age – he had a much safer plan in mind (passed down through several generations of South Georgia boys/men). Five minutes later, Ray showed up with a small gauge shotgun and a pile of shells. He took careful aim at a “primo” clump of mistletoe and blasted it to the ground where we could safely harvest it for sale. In a matter of a few minutes we had enough mistletoe to sell the whole county. I realized that this technique, while appearing crude, took some real skill to avoid blowing all the berries off the clump – and besides, the use of firearms really added to the fun.
Mistletoe has a long convoluted history of supposed magical powers and mystical properties. It was a favorite of the ancient Druids who used it to promote fertility, cure illness and treat poisoning. Mistletoe was used throughout the middle ages to ward off harmful spirits and even to prevent fires in houses. After settlement in the Americas, Europeans likely adopted our mistletoe Phoradendron spp. which looks pretty similar to the European varieties. The custom of kissing under the mistletoe may have started by the early Greeks who associated the plant with fertility and marriage rites. The Scandanavians believed that the plant represented peace and warring groups could form truces or cease fires under it. A later American custom developed into the tradition that any who kissed under this plant would likely be married.
Mistletoe is actually a hemi-parasitic plant that is capable of making its own food but also will parasitize many species of deciduous trees as well. The common species found in the S.C. lowcountry is Phoradendron serotinum but there are many other species of mistletoe in the United States. Mistletoe berries are eaten by a variety of animals – especially birds, who use the pulp as an important food source. They spread the berries to the trunks of other trees through feces where they germinate in the canopy. Modified mistletoe roots grow directly into the trunk of the host tree providing water and some energy to the plant. Mistletoe can cause problems to the host tree if its growth is not checked, by crowding out leaves the tree needs for photosynthesis, though it usually does not kill its host.
On a recent field trip (Monday), our master naturalist class was treated to something really neat. We flipped a log in a low swampy area and discovered a female marbled salamander (Ambystoma opacum) underneath. Upon closer inspection we realized that she was guarding a pile of silvery spheres (a small clutch of eggs). Female marbled salamanders lay 80 to 120 eggs under logs or in clumps of vegetation in wetland areas that are likely to flood. They will brood these eggs and even protect them from small predators like insects and other amphibians. When the fall and winter rains fill these nesting sites, the eggs hatch (within a few hours) and the larvae begin to grow and develop. After 3-8 months, the larvae metamorphose into solid dark gray salamanders and start their lives on land. They will develop the bold marbled patterns they are named for over the next few months. Males have a lighter-colored pattern than females. Adult marbled salamanders may live in the woods around the wetland and return to the same pond to breed and lay eggs.
Marbled salamanders are very handsome little beasts with striking patterns of light gray bands on a dark ground color. These chubby little guys are rarely more than five inches long from head to tail tip. They feed on small invertebrates including earthworms and a variety of insects. They have been known to live as long as ten years in the wild.
These salamanders are common residents of Carolina bays, river floodplains and other wetlands in the lowcountry. Like other amphibians, they require wetlands and a surrounding buffer of woods to carry out their lives. Some colleagues of mine have collected and released as many as twelve thousand salamanders from a single wetland about the size of a large residential yard in one day.
Many of our wetlands in the lowcountry have been destroyed or heavily altered to the point where amphibians cannot use them. Many of the wetlands that remain intact have been converted into fishing ponds making them unsuitable for most species. As you can imagine many types of fish feed on amphibians and their eggs. Proper study of the amphibian communities and the wetlands they live in will help us to understand the role that salamanders, frogs and toads play in the ecology of our area. Check out the picture taken by Jean Gilbert (a member of our current master naturalist class).
I think most of you guys realize that I have a real fondness for sharks; I am rarely not more than one association away from a conversation about these cartilaginous creatures. Beaufort County is heaven for a shark enthusiast, because we have an incredible diversity of elasmobranch fishes in the waters of Port Royal Sound. The creeks, rivers and sounds around here are home to an amazing diversity of fish, especially sharks and rays. Approximately 20 species of these non-bony fishes patrol our local creeks and rivers. Most of our sharks are relatively small species rarely exceeding 5 feet in length but many of the larger species use our local waters as "pupping" grounds venturing into Broad river and others to have their young . Port Royal Sound is even home to some of the "big boys" including tiger sharks and great hammerheads often exceeding twelve feet in length.The closely related rays are pretty abundant here as well. We have southern stingrays, Atlantic stingrays, butterfly rays, cow nosed rays and even an occasional manta ray (a species that grows to twenty feet across) as well as others.
Tiger shark
I realize this sounds like a bit of a horror story to have so many sharks around but it really is a good thing. High diversity of sharks indicates healthy waters and surrounding marsh. PRS has some characteristics that make it quite different from other aquatic systems including deep water, high salinity and high tidal amplitude. These features allow certain offshore species a place to spawn safely. We have high shark diversity for the very same reasons that we have good cobia spawning ground and great habitat for red drum.
Although shark pups can be a real nuisance as aggressive bait stealers, there is no reason to believe that sharks reduce numbers of game fish in local waters. Sharks are probably beneficial to our fishery. Certain species are indicator species (analogous to a canary in a coal mine) letting us know about water quality and the presence of certain pollutants. If particular shark species are not in an area then there is probably a good reason for it. Besides small shark pups are likely an important food source for certain commercially important species like cobia and others as well as food for bottle nosed dolphins.
