Individual study: Post-release survival of captive-reared Allegheny woodrats
Blythe R.M., Smyser T.J., Johnson S.A. & Swihart R.K. (2015) Post-release survival of captive-reared Allegheny woodrats. Animal Conservation, 18, 186-195
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Use holding pens at release site prior to release of captive-bred mammals
A replicated study in 2011–2012 in two forest sites in Indiana, USA (Blythe et al. 2015) found that when captive-bred Allegheny woodrats Neotoma magister were kept in holding pens prior to release, early survival rates were higher than those not kept in holding pens, but overall survival rates of captive-bred animals tended to be lower than those of wild resident woodrats after 4-5 months. In the first 14 days after release, seven of 16 (44%) captive-bred woodrats that were not initially kept in holding pens survived, compared to nine of 13 (69%) captive-bred woodrats that were initially kept in holding pens. After 4–5 months, captive-bred woodrats not initially kept in holding pens had significantly lower survival rates (19%) than wild-born, resident woodrats (56%). The 4-5 month survival rates of captive-bred woodrats initially kept in holding pens (31%) was also lower than wild-born, resident woodrats, but not statistically significantly lower. In April–August 2011 and 2012, a total of 29 captive-bred woodrats (>90 days old) were radio-tagged and released into two unconnected wild populations. Sixteen were directly released into the wild in 2011. Thirteen were held for two weeks in wire mesh enclosures (1.2 × 2.1 × 0.6 m) with nest boxes within the release area before release in 2012. In June–August 2011 and 2012, two samples of 16 and 17 wild-born woodrats, born that year, were radio‐tagged. Captive-bred and wild-born woodrats were radio-tracked 1–7 times/week for 4–5 months after release/tagging.
(Summarised by Ricardo Rocha)