Effects of crowding on reproductive traits of western fence lizards, Sceloporus occidentalis

  • Published source details Talent L.G. & Talent S.G. (2013) Effects of crowding on reproductive traits of western fence lizards, Sceloporus occidentalis. Herpetological Conservation and Biology, 8, 251-257.


This study is summarised as evidence for the following.

Action Category

Breed reptiles in captivity: Lizards

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Reptile Conservation
  1. Breed reptiles in captivity: Lizards

    A controlled study (year not provided) in laboratory conditions in the USA (Talent & Talent 2013) found that captive-reared western fence lizards Sceloporus occidentalis bred successfully in captivity, but that more clutches were laid and fewer eggs were infertile when female lizards were housed individually or in pairs compared to in larger groups. Individually-kept females produced more clutches (3.4 clutches laid/female) and fewer infertile eggs (11% infertile eggs/clutch) compared to females kept in groups of four or eight (2.3–2.7 clutches laid/female; 31.4–37.7% infertile eggs/clutch). Female lizards kept in pairs laid similar numbers of clutches (3.1 clutches/female) and infertile eggs (10.6% infertile eggs) to. Clutch sizes, and the proportion of females that laid eggs were similar between different sized groups (see original paper for details). Eggs from wild-caught western fence lizards were hatched and reared in captivity. In total, 96 nine-month-old female lizards were housed either individually or in groups of two/cage, four/cage or eight/cage (24 lizards/treatment) for the breeding season. One male lizard was randomly assigned to each cage for breeding. Eggs were collected from cages within 12 hours of being laid. Females and eggs were monitored until egg-laying ceased and egg fertility was assessed by ‘candling’.

    (Summarised by: Katie Sainsbury)

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