Yes, those were the only values I tested here. I agree that it would be interesting to look at a wider range of salinities. I chose 25% sea water because some literature has reported optimal growth at that concentration. As for dehydration, the experimental tubs are maintained outside and are exposed to rain, which is how terrapins get fresh water naturally. (The tubs are changed daily to maintain the respective salinities). Food also provides some hydration. I did not see any fungal growth in the freshwater. In both the freshwater tub and the 50% seawater tub there were some individuals that just did not grow at all, regardless of the fact that they were eating. This was not observed in any of the turtles in 25% seawater.



It is important to note that the salinity of the water in the marsh right around where the eggs are laid, and where the hatchlings emerge, is consistently around 32 ppt (sea water). This raises the question as to whether the hatchlings seek out fresher water, and if so where are they going? These would be good topics for future research...I am in the process of putting together a powerpoint presentation summarizing the results (which will be presented at a public meeting here on Aug. 7). I can send you the powerpoint file if you're interested.



-Zach

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