Conservation translocations of fauna in Aotearoa New Zealand: a review

Abstract

<p>The biological changes that have occurred in Aotearoa New Zealand following human settlement are well documented with almost all ecosystems and taxa having been negatively impacted. Against this background of loss there have been remarkable advances in conservation management, particularly in the large-scale eradication and control of exotic mammalian pests. In 2016, the New Zealand Government announced Predator Free 2050, an ambitious project to eradicate introduced predators in Aotearoa New Zealand by 2050. Here, we discuss conservation translocations in the context of Predator Free 2050 aspirations. Our review draws together knowledge from Aotearoa New Zealand’s rich history of translocations and outlines a framework to support translocation decision making in the predator-free era. Predator Free 2050 aspirations encompass an ongoing question in conservation management; should we focus on maintaining small protected populations, because this seems generally easier and currently achievable, or on reversing declines in the large mainland areas that contain most of our biodiversity, a much harder challenge largely reliant on the continued use of aerially applied toxins? We focus on successfully establishing small translocated populations because they will provide the source populations for colonisation of a predator-free landscape. We define a successful translocation as one that meets a clear set of fundamental objectives defined a priori. If translocation objectives are clearly defined all subsequent decisions about factors that influence conservation translocation outcomes (e.g. the cultural and social setting, pest thresholds, habitat quality, genetic management) will be easier. Therefore, we encourage careful thinking in formulating conservation translocation objectives that align with aspirations for a predator-free Aotearoa NZ. We discourage a focus on any single element of planning and rather encourage all people involved in conservation translocations, particularly decision makers, to explicitly recognise the multiple values-based objectives associated with conservation translocations.</p>

Review of hyperdispersal in wildlife translocations

“…Increasing the release group by this proportion could assist with establishment after release and may be particularly useful for species that are hard to monitor. Conversely, it may be the case that releasing more individuals may not increase translocation success and will just lead to an increased rate of loss of individuals through competition with conspecifics (Innes et al., 2022; Parker et al., 2020). However, we found no significant relationship between cohort size and incidence of hyperdispersal, suggesting that, although increasing cohort size may lead to more individuals dispersing overall, the number of individuals that establish at the release site will also increase proportionately ( p = 0.265, Pearson correlation).…”

A review of New Zealand native frog translocations: lessons learned and future priorities

“…scientists might focus on ecological restoration or long-term species survival, while tangata whenua may see their involvement as an expression of kaitiakitanga, place-based customary responsibilities and practices of Māori whose genealogical history connects them to land, based on principles of reciprocity and the desire to maintain these relationships for future generations (McAllister et al 2019). A local community member may simply appreciate the joy of knowing a species is nearby (Cisternas 2019;Cisternas et al 2019;Parker et al 2020). These objectives are not mutually exclusive, but it is important to understand this element of conducting a successful translocation at the outset and know that it can be achieved by meaningful stakeholder engagement (Parker et al 2020).…”

“…A local community member may simply appreciate the joy of knowing a species is nearby (Cisternas 2019;Cisternas et al 2019;Parker et al 2020). These objectives are not mutually exclusive, but it is important to understand this element of conducting a successful translocation at the outset and know that it can be achieved by meaningful stakeholder engagement (Parker et al 2020).…”

“…Translocation is an important conservation tool in New Zealand (Jones & Merton 2012;Miskelly & Powlesland 2013;Miller et al 2014;Romijn & Hartley 2016;Jahn et al 2022). Its success has been due in great part to the fact that the decline of much endemic wildlife has been caused by introduced mammalian species, and because numerous offshore islands exist which are either predator-free or where eradication efforts are relative straightforward (Armstrong & McLean 1995;Jones & Merton 2012;Parker et al 2020). Several hundred conservation translocations have been carried out in New Zealand, the majority of which have been for birds (Miskelly & Powlesland 2013) although many herpetofauna and invertebrate translocations have also been performed (Towns & Ferreira 2001;Sherley et al 2010;Miller et al 2014;Romijn & Hartley 2016;Towns et al 2016).…”