Measurements

Measurements to take of captured turtles

Once captured, turtles are measured for the following characteristics and photos are taken of the carapace, plastron, head and left/right front feet claws. Please note that permits are required to handle turtles and other wildlife in BC.

  • Weight (kg)
  • Height (cm)
  • Plastron's straight width and length (cm)
  • Carapace's straight width and length (cm)
  • Right and left front middle claws (cm)
  • Total tail length, tail length to cloaca, tail width at cloaca (cm), some takes the tail with at the carapace but it is variable
  • Sex and age are determined based on measurements and overall appearance (e.g., males are generally smaller, have longer claws, and a longer proportional distance of their tail to their cloaca from the plastron)
  • Note any special identifying features, such as scaring, are also noted.
  • When required, blood samples may be collected (up to 20 turtles per location is desirable, but the actual number of samples depends on the objectives of the study).
  • To identify individual turtles for mark-recapture studies, turtles are notched on both sides of their carapace (Figure 1).
  • When required by the study objectives, transmitters can be affixed to adult turtles via bolts to two lower scutes (usually 9 and 10, or scutes number 6 and 7 in the marking scheme below - Figure 1), or via an epoxy glueing method to the very top part of the carapace (further comments in the tagging section below from groups who have done this).

Example of datasheet for capturing morphological data:

WPT Measurement data sheet