Identification of stimuli and challenges to improve the environment of captive kea

Student thesis: Doctoral ThesisDoctor of Philosophy (PhD)


Inadequate environments can compromise the well-being of captive animals, at least in part because they may inhibit the expression of behavioural needs. There are several complementary approaches to assessing captive animal well-being, such as “function”, “feelings” and “natural-living” approaches. These rely on specific indicators (e.g. of physical health, fitness, physiology, suffering, expression of natural behaviours, motivation, and affective states) to assess if animals have poor or good well-being. To address the potential shortcomings of captive environments and improve captive animal well-being, additional stimuli, resources, or other behavioural engagement opportunities are often provided as environmental enrichment. Such “enrichment”, however, is commonly provided merely under the assumption that its well-being effects will be positive, with no prior evaluation. In addition, research on captive animal well-being can be biased towards certain enrichment types and certain taxa.

This thesis consists of a systematic investigation of stimuli, resources, and challenges to improve the environment of an understudied species of captive psittacine, the kea (Nestor notabilis), with a view to improving its well-being in captivity.

Kea are common across European zoos but research on their husbandry conditions and well-being is lacking. Information on other parrot species and on the behaviour of wild kea suggests that their well-being could be compromised in captivity. This thesis therefore starts with a survey of the husbandry and well-being of captive kea distributed to keakeeping institutions. It finds that behaviours recognised as indicators of poor well-being in other captive psittacines (pacing, feather damaging, and abnormal reproduction) are also present in the kea population. It furthermore shows that enrichment practices have a bias towards foraging interventions.
This thesis then investigates a range of environmental stimuli and challenges identified as holding potential for improving captive kea well-being. This covers the effects of sensory stimulation on captive kea behaviour, of foraging interventions to promote foraging behaviours, and identifies preferred manipulations and challenges on the basis that animals have been shown to make choices that positively affect their well-being. Sensory stimulation is found to increase naturalistic behaviours and decrease behaviours associated with poor well-being and is thus interpreted as having a positive effect on kea well-being. Kea are found to contrafreeload, highlighting their motivation to perform a range of foraging strategies. Kea preferred to manipulate membranes when solving a foraging task and choose more often an arm of a T-maze containing a difficult visual discrimination task when an easy task was the alternative. These thesis findings may be used to shape improvements to captive kea well-being by designing motivating engagement opportunities that allow the expression of key behaviours.
Date of Award29 Sep 2020
Original languageEnglish
Awarding Institution
  • The University of Bristol
SupervisorMichael T Mendl (Supervisor) & Suzanne D E Held (Supervisor)

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