Preparing captive-bred birds for reintroduction: the case of the Vietnam Pheasant Lophura edwardsi

Abstract

Summary The Vietnam Pheasant Lophura edwardsi (including L. hatinhensis) is only known from a small area of central Vietnam, where it occurred in wet forest below 300 m. It is probably extinct in the wild, but some 1,500 birds, derived from 28 individuals caught in 1924–1930, survive in captivity. Guidelines for reintroducing galliforms date from 2009. Subsequent literature was reviewed for new research findings to help maximise the chances of success in reintroducing birds. Studies confirmed that non-parent-reared captive-bred galliforms survive poorly, primarily owing to inadequate anti-predator responses. These reflect both genetic and ontogenetic unsuitability to wild conditions, with progressive maladaptation of stock being related to the number of generations spent in captivity (at least 35 in the case of Vietnam Pheasant). To compensate as far as possible for this deficiency, a reintroduction programme should use: environmental enrichment (including the provision of perches in aviaries), dietary enrichment (especially involving practice with live food), parent-rearing over several generations (although how many are needed for a species almost a century in captivity is unknown), soft releases (allowing full familiarisation with the future environment over at least 50 days), rigorous anti-predator training (against both air and ground attacks), anti-predation release stratagems (relocating and deterring predators, releasing birds at several stations, offering post-release support), determining appropriate numbers (per batch, with at least 300 in total per site) and time-frame for release (around five years) and the selection of fully suitable releasees in (as far as possible) naturally formed social groups, including parent-guided offspring aged around four months. Six sites need survey for extant populations or use for reintroduction, and the choice of reintroduction site will depend primarily on habitat extent and condition. The costs of these measures will be high and the overall project schedule will need to extend beyond the overall five years currently planned.

Is there any suitable habitat left for the Critically Endangered Gurney’s Pitta’s in Thailand? Implications for species management

“…Furthermore, snakes are typically the most important or second-most important nest predators depending on the species of bird (Pierce and Pobprasert 2013, Khamcha and Gale 2020). Thus, despite the naturally high nest predation rates in the region, managing nest predators and/or protecting birds and nests from predators, is recommended because reintroduced birds appear more vulnerable to predation pressure compared to those born in the wild (Collar 2020).…”

Extinct in the wild: The precarious state of Earth’s most threatened group of species

“…Bearing in mind the threat of an oncoming wave of extinctions over the coming decades (54), a considerable number of ex situ-restricted species may therefore be accumulating with no reliable way of identifying them. Species that have recently been claimed to probably qualify as EW but are not yet assessed as such include the ʻālula (Brighamia insignis) (43), a shrub native to Hawaii, the Vietnam pheasant (Lophura edwardsi) (55), and the Javan pied starling (Gracupica jalla) (56), all of which are classified as Critically Endangered, but only the first bearing the "Possibly Extinct in the Wild" tag.…”

Captive breeding and the conservation of the threatened houbara bustards

“…Learnt behaviours are also prone to loss in captivity (Snyder et al 1996), particularly during chick-rearing (Collar 2020), with consequences for post-release survival. Loss of parental learnt behaviour may contribute to lower reproductive success in released head-started birds (e.g.…”

“…Roche et al 2008). Captivebred released galliforms frequently have lower survival and breeding success than their wild counterparts, reflecting in particular their failure to acquire appropriate anti-predator behaviours (Rantanen et al 2010, Rymešová et al 2013, Collar 2020. Predatoraversion training improved post-release survival of farmed red-legged partridges (Gaudioso et al 2011), but has generally produced mixed results (Berger-Tal et al 2020), particularly for bird translocations (Tetzlaff et al 2019), and is often labour-intensive, costly and potentially hazardous.…”