INDIVIDUAL IDENTIFICATION OF THE LAKE OKU CLAWED FROG (XENOPUS LONGIPES) USING A PHOTOGRAPHIC IDENTIFICATION TECHNIQUE

Aevarsson, U; Graves, A; Carter, KC; Doherty-Bone, TM; Kane, D; Servini, F; Tapley, B; Michaels, CJ

Abstract

Amphibians are challenging to mark for recapture due to their small size and permeable, sensitive, and often frequently shed skins. Photographic identification and pattern matching techniques are increasingly used as a non-invasive method to identify individual amphibians for the purposes of monitoring individuals over time. The Critically Endangered Lake Oku Clawed Frog (Xenopus longipes) has distinctively patterned ventral patterns as adults. We used Wild-ID to explore the use of photographic identification for the longitudinal identification of both adult and juvenile X. longipes. We photographed juvenile frogs twice over a 180-d period and adult frogs seven times over 624 d. Juvenile belly patterns underwent marked ontogenetic shifts over the 180-d period and Wild-ID was not able to match photographs of the same individuals over the study period. Markings were more stable in adult frogs and Wild-ID was successful in matching photographs of individual adult frogs over 180 d but became less effective at distinguishing between individuals at 624 d (i.e., Wild-ID similarity scores halved and false rejection rates increased substantially). We detected no false acceptances. Our results provide evidence to guide management of this species in captivity and in the field and demonstrate the importance of considering life-stage linked ontogenetic changes when validating a photographic identification method for amphibians.

Citation

Aevarsson, U., Graves, A., Carter, K., Doherty-Bone, T., Kane, D., Servini, F., …Michaels, C. (2022). INDIVIDUAL IDENTIFICATION OF THE LAKE OKU CLAWED FROG (XENOPUS LONGIPES) USING A PHOTOGRAPHIC IDENTIFICATION TECHNIQUE. Herpetological Conservation and Biology, 17(1), 67-75

• Journal Article Type: Article
• Acceptance Date: Feb 14, 2022
• Publication Date: Apr 30, 2022
• Deposit Date: Jul 28, 2023
• Publisher: Herpetological Conservation and Biology
• Peer Reviewed: Peer Reviewed
• Volume: 17
• Issue: 1
• Pages: 67-75
• Keywords: amphibian; Anura; Cameroon; ontogenetic change; pattern matching; photographic individual identification; zoo; PHOTO IDENTIFICATION; MARK-RECAPTURE; ANURA; PHOTOIDENTIFICATION; PATTERN; RECOGNITION; AMPHIBIANS; RETENTION; SOFTWARE; TOADS
• Publisher URL: https://www.herpconbio.org/contents_vol17_issue1.html