Feasibility and pitfalls of ex situ management to mitigate the effects of an environmentally persistent pathogen

Abstract

AbstractEx situ (captive) management can facilitate species recovery, but this approach is invasive and is not universally appropriate. Evidence‐based approaches are critical to determining whether ex situ approaches will be effective, but in many cases biological and ecological data from threatened populations are scarce. We generated a structured set of general biological and social/logistical criteria required for captive management to benefit threatened, free‐ranging populations. We illustrate how these criteria can be applied using a case study where populations are severely threatened, but demographic data are scarce (white‐nose syndrome in Canadian bats). Using (1) population viability modelling (PVA), (2) a survey of Canadian zoos and wildlife rehabilitators, and (3) literature reviews, we identified two of our five initial target species as potential candidates for captive management. PVA revealed that sustainable captive colonies require high adult survivorship relative to free‐ranging populations. Our survey and literature reviews showed that Canadian zoos and wildlife rehabilitators are enthusiastic about bat conservation. However, none could currently maintain the target species, due to limited infrastructure and/or knowledge gaps related to husbandry and reintroduction of captive bats to the wild. Captive management is unlikely to stabilize target populations because released bats risk re‐infection. We conclude that ex situ management is not an appropriate tool in our case study, and would represent ineffective use of available conservation resources. However, development of captive husbandry and re‐introduction methods for hibernating, insectivorous bats would contribute to our global capacity to conserve similar species.