Posted: Tue Apr 04, 2006 12:17 pm
The measuring thing? Measure the length of your turtle's shell from the scute in back of the neck down the spine to the end of the one above the tail. Don't include the curve of the shell. The result is call the Straight Carapace Length (SCL).
For the cuttlebone, I keep several head-size pieces in my RES's tank and replace them as they disappear. (A few sink to the bottom, and I leave them there.) I've noticed that some cuttlebone tends to leave a little film on the water. If the dust is making the water cloudy, try rinsing it before you put it in the tank.
In nature, a turtle would spend a fair amount of time foraging for food---food wouldn't be available daily as it is for captive turts. Some days a wild turtle would go without, and the days that the turtle found an abundance of food, the turtle would probably gorge itself (opportunistic eating) because the next meal would not be a given.
Cantelope contains beta carotene, a precursor to Vit A. A turtle wouldn't enounter cantelope in the wild, true, (but I have been told of a wild boxie that found someone's berry bushes and was able to clean the branches that could be reached clean of the berries) but the beta carotene is a safe way for a turtle to get Vit A in the diet, turtles usually like cantelope because of its rather strong smell, and it's safe to give occasionally as part of the overall diet. Wild turtles would be getting Vit A from other sources in the wild, but since their diets can't be copied exactly, giving a food that contains that Vitamin in a different food isn't a bad thing to do.
I think turtles if possible adjust their diet to their needs. They're programmed to seek calcium, for example, and it's though this is a reason why captive turts try to eat pebbles/gravel in the tank (and why not having gravel in the tank and having cuttlebone in the tank is good). This isn't so different from humans (when you feel thirsty or want something salty to eat, for example).
I don't know if wild turtles require more protein than captive ones, but suspect it would be as I mentioned above--if they went without protein for a while that's what they'd be looking for and most apt to consume. But in the absence of that, they'd eat whatever they could find.
"You become responsible, forever, for what you have tamed." -Antoine de Saint Exupery-