Monitoring our hatchlings’ biometrics is very important because it gives us a good indication of whether or not the turtles are healthy. Once a week, after all the essential housekeeping tasks have been done, we measure and weigh the turtles one by one. They are first dried by gentle patting with a towel to remove any ‘water weight’ before being put on the scale. After their weight has been recorded, their carapace (shell) length is then measured using callipers. This can be of varying difficulty depending on how active the turtle is and whether you’re trying to read the digital or manual calipers.
These measurements help track the development of the turtles and whether we need to give extra support to a particular individual. Specifically, the average weight of the turtles determines how much food they each receive; however, if one turtle is significantly lighter and smaller than the others, it will receive an extra gram of food and be under observation until its development is back on track with the others. Happily, our hatchlings are all doing very well and are now averaging 119.5 g compared to 26.6 g when they first hatched 6 months ago.
Once a month, after their measurements have been recorded, each turtle is photographed from above and below for future reference. The hatchlings, however, aren’t always the best models; they tend to flap a lot and a wayward flipper occasionally gets in the way, which makes for a blurry picture.
Written by Rebecca Diggins and Eleri Kent