Logo image
Assessing age in the desert tortoise Gopherus agassizii: testing skeletochronology with individuals of known age
Journal article   Open access

Assessing age in the desert tortoise Gopherus agassizii: testing skeletochronology with individuals of known age

Amanda Curtin, George Zug, Philip Medica and James Spotila
Endangered species research, v 5(1), pp 21-27
01 Jan 2008
url
https://doi.org/10.3354/esr00108View
Published, Version of Record (VoR)Maybe Open Access (Publisher Bronze) Open

Abstract

Gopherus Gopherus agassizii
Eight desert tortoises Gopherus agassizii from a long-term mark- recapture study in the Mojave Desert, Nevada, USA, afforded an opportunity to examine the accuracy of skeletochronological age estimation on tortoises from a seasonal, yet environmentally erratic environment. These 8 tortoises were marked as hatchlings or within the first 2 yr of life, and their carcasses were salvaged from predator kills. Using a blind protocol, 2 skeletochronological protocols (correction-factor and ranking) provided age estimates for a set of 4 bony elements (humerus, scapula, femur, ilium) from these tortoises of known age. The age at death of the tortoises ranged from 15 to 50 yr. The most accurate protocol - ranking using the growth layers within each of the 4 elements - provided estimates from 21 to 47 yr, with the highest accuracy from the ilia. The results indicate that skeletochronological age estimation provides a reasonably accurate method for assessing the age at death of desert tortoises and, if used with a large sample of individuals, will provide a valuable tool for examining age-related mortality parameters in desert tortoise and likely in other gopher tortoises (Gopherus).

Metrics

8 Record Views
18 citations in Scopus

Details

Logo image