Re: Digest Number 304

About salt in the water. Remember that near shore ocean water is about 28 ppt (parts per thousand), and in the estuaries and bays (we call them sounds in NC) it runs anywhere from 8 to 19 ppt. Open ocean is about 30 ppt, so if you are looking for a 25% salinity, you want about 7 to 8 ppt. I have seen terps living in a creek in S. Ga. that fluctuated between 7 and 19 ppt. (I think we saw it once at 24) depending on the tide and rainfall. I do not remember how to calculate Specific Gravity into ppt. (I am a Naturalist after all, not a Mathematician), but Terps can withstand water all the way from fresh to the salinity of the ocean. They are good in this way, and some Herpetologists think that they colonized the estuarine systems and found a niche after separating from their Emydid kin (probably Malaclemys, the Maps), which allowed them a niche without competition from the aquatic fresh water turtles. They still, however, are able to do quite well without salt, but some think they would not be able to compete in a fresh water environment. I would say it is up to the human who is owned by these magnificent critters! Alex Netherton The Appalachian Naturalist Asheville, NC http://www.appalachian-naturalist.com alex@…