Diamondbacks And Their Interactions

Chemical Interaction

Terrapins from 4 sites in South Carolina and a superfund site in Brunswick, Georgia were used to measure levels of mercury in the surrounding areas. Blood and scute samples were taken from each captured specimen and used to measure the levels of mercury. Mercury levels were much higher in the terrapins caught near the superfund site in Georgia than the terrapins caught in South Carolina. The terrapins eat lots of periwinkles and other scavengers such as small fish which directly absorb mercury from being so low on the food chain and coming into direct contact with the chemical by means of being scavengers. There were also seasonal fluctuations of blood mercury levels from the terrapins collected in South Carolina. Levels of mercury were significantly lower in August than in April, June or October. However the levels of mercury in the scute samples did not vary seasonally. 90% of the mercury found in the terrapins is in an organic form.

Geological Interaction

The habitat range of the Diamondback Terrapin stretches from the Gulf Coast of Texas, around Florida, all the way up the East Coast to Cape Cod, Massachusetts. I have personally seen one of these terrapins on Cape Cod during the summer. It was crawling through some sea grass during low tide in Cape Cod by, just south of Campground Beach in Eastham, Ma. Although these terrapins are near threatened, the highest concentration of their total population can be found in the Maryland, Delaware, Chesapeake Bay area. Along the coasts of the Carolinas is also another hot spot for these creatures.

Physical Interaction

The Diamondback Terrapin is very sensitive to changes in salinity as well has big changes in water levels. They are directly impacted by their habitat which include coastal salt marshes, some estuaries and sea grass along beaches. Their habitat is very vulnerable to changes in salinity and large variations in water level. Drastic levels in salinity could kill the vegetation they use for protection, as shelter, and to look for food around. Too much or too little salinity could kill off this grass, leaving the terrapins with no places to live. Also the tides and level of water plays a big factor on their habitats. If the water level rises too much the salt marshes and other places they live will flood too much making it impossible for the terrapins to survive there in all that water. They prefer sandy beaches to nest on, so again if the water level rises too much the nests are put in jeopardy of being flooded out. This would result in the population of terrapins not being replenished and even less of these animals left in the world. Another aspect to be considered is if the tide sinks too low. During the winter months these terrapins hibernate like most reptiles. They dig down into the mud of the salt marshes and spend the winter hibernating down there. If the water were to sink to low it could expose the mud and cause it to freeze over. This in return would also freeze the turtle hibernating in that mud to death. As a fun fact the Diamondback Terrapin is the only turtle in the world that can tolerate Brackish Water. In other words they are the only turtles that can tolerate both fresh and low salinity salt water. That is why salt marshes make the perfect habitat fro them, there is some salt but not full blown salt water from the open ocean.

Sources:

Gaëlle Blanvillain, Jeffrey A Schwenter, Rusty D Day, David Point, and et al. "DIAMONDBACK TERRAPINS, MALACLEMYS TERRAPIN, AS A SENTINEL SPECIES FOR MONITORING MERCURY POLLUTION OF ESTUARINE SYSTEMS IN SOUTH CAROLINA AND GEORGIA, USA. " Environmental Toxicology and Chemistry 26.7 (2007): 1441-1450. ProQuest Science Journals, ProQuest. Web. 20 Apr. 2011.