Behaviour of Captive-bred Grey Partridges (Perdix perdix) and its Implications for Reintroduction Success.

Abstract

Wildlife re-introductions have become an important tool in restoring animal populations and even saving species from extinction, but the success rates of these efforts have been low. Behavioural deficiencies in captive-bred animals increasing susceptibility to predation are among the main problems causing failure in reintroductions, but only recently has behaviour been given proper attention in reintroductions. Through behavioural research to uncover maladaptive behaviour, this doctoral thesis aims at elucidating reasons for previous poor success in reintroductions of grey partridges Perdix perdix, a conservation priority species in the UK, and addresses important behavioural issues hindering success in wildlife re-introductions. For this, I released captive-bred grey partridges onto sympathetically managed farms in Oxfordshire and east Gloucestershire, UK, as pairs in spring 2007 and as family groups, i.e. coveys, in autumns 2006 and 2007. By using radio telemetry, I then monitored habitat use, observed vigilance behaviour and time budgets and recorded nocturnal roosting behaviour in the released birds as well as monitored their survival. Before the releases in autumn 2007, the grey partridges were also tested in captivity for their temperament and monitored after release to investigate whether temperament could have predicted survival. The post-release behavioural studies revealed that released grey partridges were vulnerable to an ecological trap created by field margins in spring, showed poor vigilance and inappropriate feeding behaviour compared to previous knowledge on wild grey partridges, and performed anti-predator roosting behaviour variably and inconsistently. The temperament tests indicated that the captive population of grey partridges consisted of individuals with variably fearful disposition, although the animal's behaviour in the tests did not predict post-release survival. This thesis demonstrated how post-release behavioural monitoring can reveal weaknesses in the behaviour of the released animals, as well as the importance of developing rearing methods to maintain wariness, adaptive feeding routines and anti-predator roosting behaviour in the captive-bred population.