Timing of birth and body condition in neonates of two gartersnake species from central Mexico

  • Published source details Manjarrez J. & San-Roman-Apolonio E. (2015) Timing of birth and body condition in neonates of two gartersnake species from central Mexico. Herpetologica, 71, 12-18.


This study is summarised as evidence for the following.

Action Category

Maintain wild-caught, gravid females in captivity during gestation

Action Link
Reptile Conservation
  1. Maintain wild-caught, gravid females in captivity during gestation

    A replicated study in 1991–2004 in laboratory conditions in the State of Mexico, Mexico (Manjarrez & San-Roman-Apolonio 2015) found that wild-caught, gravid Mexican garter snakes Thamnophis eques and blackbelly garter snakes Thamnophis melanogaster successfully gave birth to live offspring in captivity. Mexican garters produced 275 live offspring and 13 dead offspring from 21 litters, and blackbelly garters produced 325 live, and 15 dead offspring from 43 litters. The sex ratio for Mexican garters was even (125 males, 146 females, and 4 unsexed), whereas blackbelly garters produced more than twice as many female as male offspring (99 males and 226 females). In 1991–2004, twenty Mexican garter snakes and 43 blackbelly garter snakes that were found to be gravid (by palpating for presence of embryos) were brought into captivity. Snakes were maintained in individual terraria with a paper substrate and a water bowl. Temperatures ranged from 20–25°C. Two to three weeks after birth, adult snakes and their offspring were released where they had been captured.

    (Summarised by: William Morgan)

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