904 S. P. Mahood et al.


2011). Lines between states are increasingly blurred as a re- sult of the increase in ex situ management (Redford et al., 2012) and the variety of ex situ management regimes from small cages to extensive semi-natural environments.Wefol- low the intuitive definition in IUCN/SSC (2014), which de- fines ex situ as conditions under which ‘the individuals are maintained in artificial conditions under different selection pressures than those in natural conditions in a natural habi- tat’. Duration of time in ex situ conditions can vary from short, for example the temporary removal of a popula- tion during predator control, to indefinite, for species for which there is no hope of reintroduction in the foreseeable future. Ex situ management has a range of purposes, in- cluding conservation (through establishing insurance pop- ulations, breeding for reintroduction, head-starting and research), education and restocking for sport (Fischer & Lindenmayer, 2000; Harding et al., 2016). Here we consider only captive breeding for preventing extinctions of species (i.e. the complete loss of all individuals of the species), forwhichwe use the term ex situ conservation. The ultimate goal of ex situ conservation in this context is the reinforcement or reintro- duction of wild populations, which distinguishes it from capture solely to establish captive populations for display, edu- cation, farming or keeping as pets. For this reason, individuals maintained and bred for ex situ conservation should be theor- etically capable of producing offspring that can survive in the wild. Ideally, where possible, a parallel programme of in situ conservation should ensure that populations are maintained in the wild. However, ex situ conservation can inadvertently compromise source populations by harvesting toomany indi- viduals from free-ranging populations (increasing rates of de- cline), or distracting decisionmakers such as governments and funders to the detriment of in situ conservation (Snyder et al., 1996). The IUCNguidelines suggest that success of in situ con- servation should not be unduly jeopardized by ex situ conser- vation (IUCN/SSC, 2013, 2014) unless conditions in the wild are so hostile that the ex situ conservation plan requires that the entire wild population is taken into captivity (McCleery et al., 2014). Ex situ conservation can buy time for conservation man-


agers to address causes of decline by eliminating introduced predators, restoring habitat or enacting legislative changes that create conditions for species to survive in a wild state (Andrew et al., 2018), but it must begin when there are suf- ficient wild individuals to establish a captive population. Species whose extinction might otherwise have been pre- vented, such as a number of reptiles and a bat (Christmas Island pipistrelle Pipistrellus murrayi) endemic to Christmas Island, and the po‘ouli Melamprosops phaeosoma,were lost because plans for ex situ conservation were not enacted until too few individuals remained (VanderWerf et al., 2006; Martin et al., 2012;Andrew etal., 2018). Although most risks emanating from ex situ conservation can be mitigated, this is costly and time-consuming and none can be prevented


entirely. However, avoidance of decisions about ex situ conservation because of perceptions of risk, fear of failure and fear of being perceived to havemade the wrong decision is itself a decision to do nothing (Brook et al., 2014) and can lead to extinctions (Woinarski et al., 2017). IUCN has developed guidelines to help conservation


managers determine how and when ex situ management should be used in conservation (IUCN/SSC, 2014). The guidelines provide a logical five-step decision-making pro- cess that finishes with a call to make a decision that is in- formed by the information gathered in the preceding four steps and ‘weighing the potential conservation benefit to the species against the likelihood of success and overall costs and risks of not only the proposed ex situ programme, but also alternative conservation actions or inaction’ (IUCN/ SSC, 2014; McGowan et al., 2017). Step 1 is a review of the status of the species, in Step 2 the role(s) that ex situ management could play in the conservation of the species are defined, Step 3 is an evaluation of the precise nature of the desired ex situ population to meet identified role(s), and in Step 4 resources, expertise, feasibility and risks are appraised (McGowan et al., 2017). There is no method proposed for the critical fifth step, which is to make the decision on whether to initiate captive breeding. Because captive breeding for conservation can be risky and con- troversial, decision-making should be conducted using a method that enables wide participation in the process so that practitioners have ownership of the results rather than feel- ing disempowered by top-down systems of management (Black et al., 2011). Hidden value judgments can be revealed and managed by following a transparent process that docu- ments why and how decisions were made, with uncertainty acknowledged and quantified where possible so that it can be incorporated into the decision-making process (Game et al., 2013). However, without the aid of tools, people strug- gle to quantify risk in decision-making processes (Redford & Taber, 2000). The tool used most commonly for struc- tured decision analysis in conservation is the decision tree (Maguire, 1986; Gregory et al., 2012; Panfylova et al., 2019). Decision trees have been used to choose between ex situ conservation and other options to varying degrees of suc- cess, but when a species is under imminent threat of extinc- tion in the wild the chance of success for any conservation plan is low (Regan et al., 2005). Here, we apply the IUCN Guidelines (IUCN/SSC, 2014)


to the South-east Asian subspecies of Bengal florican Houbaropsis bengalensis blandini, a Critically Endangered bustard now restricted to Cambodia (BirdLife International, 2018b). Although IUCN/SSC (2014) calls for dissemination of information regarding use of the guidelines, we have not found any peer reviewed articles that explicitly document their use. Since the mid 2000s (the date of the first reliable population data), the Bengal florican has experienced a de- cline of.10%per annum (Gray et al., 2009; Packman et al.,


Oryx, 2021, 55(6), 903–915 © The Author(s), 2021. Published by Cambridge University Press on behalf of Fauna & Flora International doi:10.1017/S0030605319001510


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