Population demography of an endangered lizard, the Blue Mountains Water Skink.

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Etat: Public
Version: de l'auteur⸱e
ID Serval
serval:BIB_B0289757E3E9
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
Population demography of an endangered lizard, the Blue Mountains Water Skink.
Périodique
BMC Ecology
Auteur⸱e⸱s
Dubey S., Sinsch U., Dehling M.J., Chevalley M., Shine R.
ISSN
1472-6785 (Electronic)
ISSN-L
1472-6785
Statut éditorial
Publié
Date de publication
2013
Volume
13
Pages
4
Langue
anglais
Résumé
BACKGROUND: Information on the age structure within populations of an endangered species can facilitate effective management. The Blue Mountains Water Skink (Eulamprus leuraensis) is a viviparous scincid lizard that is restricted to < 40 isolated montane swamps in south-eastern Australia. We used skeletochronology of phalanges (corroborated by mark-recapture data) to estimate ages of 222 individuals from 13 populations.
RESULTS: These lizards grow rapidly, from neonatal size (30 mm snout-vent length) to adult size (about 70 mm SVL) within two to three years. Fecundity is low (mean 2.9 offspring per litter) and is affected by maternal body length and age. Offspring quality may decline with maternal age, based upon captive-born neonates (older females gave birth to slower offspring). In contrast to its broadly sympatric (and abundant) congener E. tympanum, E. leuraensis is short-lived (maximum 6 years, vs 15 years for E. tympanum). Litter size and offspring size are similar in the two species, but female E. leuraensis reproduce annually whereas many E. tympanum produce litters biennially. Thus, a low survival rate (rather than delayed maturation or low annual fecundity) is the key reason why E. leuraensis is endangered. Our 13 populations exhibited similar growth rates and population age structures despite substantial variation in elevation, geographic location and swamp size. However, larger populations (based on a genetic estimate of effective population size) contained older lizards, and thus a wider variance in ages.
CONCLUSION: Our study suggests that low adult survival rates, as well as specialisation on a rare and fragmented habitat type (montane swamps) contribute to the endangered status of the Blue Mountains Water Skink.
Mots-clé
Australia, Montane species, Reptile, Skeletochronology
Pubmed
Web of science
Open Access
Oui
Création de la notice
10/07/2012 9:38
Dernière modification de la notice
20/08/2019 15:19
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