Zoos and aquariums that are part of the World Association of Zoos and Aquariums reach over 700 million visitors every year. These institutions are also among the main global providers of conservation funding, investing more than US$ 350 million on ex situ and in situ wildlife activities annually (Gusset & Dick, 2011). But, even though these institutions regularly champion species and habitat protection causes, exhibiting and breeding wild animals in human care are still their main commercial and conservation-related activities.

Arguably, as a result of the tensions arising from balancing visitor expectations and dedicating resources (financial or others) to biodiversity conservation, the number of threatened species saved from extinction by zoos is still low (Fa, Funk & O'Connell, 2011). However, conservation breeding has played a major role in the recovery of 16 out of 68 species, and in at least 13 of these, zoos have been instrumental (Hoffmann et al., 2010; Conde et al., 2011a). Given such precedents, some authors have argued that zoos should invest more in keeping larger numbers of threatened species in their collections. Nonetheless, the suggestion that zoos should be prepared to open up more physical (and arguably philosophical) space for species requiring urgent conservation attention (via conservation breeding and release into the wild) has led to wide divisions within the profession.

This is best illustrated by the arguments put forward by Hutchins, Willis & Wiese (1995) who disputed the need for zoos to adhere to a ‘Noah's ark paradigm’; the idea that conservation investments by these institutions should not hang on selecting species solely on the possibility of a future reintroduction. These authors reasoned that serious consideration should be given to the ability of a species to contribute to more immediate conservation goals, including public education, fundraising to support field conservation and scientific research – in their words, strategic collection planning. They further emphasized that long-term breeding programs should primarily concentrate on flagship species – ‘those that have the potential to excite public attention and help to protect habitat and other taxa’ – rather than on a broad array of species that are currently threatened.

Zoos are chimeras and like the mythological beasts, are metaphorically composed of the parts of three institutional types: a business, a conservation body and a school. Zoos have to manage wild animals in human care for exhibition purposes and to make money, they have to educate the large numbers of people that come to enjoy the spectacle of wild animals, but they are also obliged (often by law in some countries) to contribute to safeguarding biodiversity. The latter is often achieved by interorganizational conservation breeding programs and/or in situ conservation projects. However, unlike the chimeras of ancient Greece, zoos have a formidable challenge in balancing out the leanings of each of its three animal (institutional) body parts.

Zoos, like many other institutions involved in conservation, are shaken by non-science aspects, which reflect the pressure of multiple factors (e.g. societal values or even internal corporate biases). Possibly, the strongest conditioner affecting zoos is related to anthropomorphic factors, such as the preference for the conservation of more ‘charismatic’ species. Zoos are also affected by anthropocentric factors; for example, the imperative of making money over funding conservation activities by the institution (Restani & Marzluff, 2002). As a result, zoos will focus most exhibit, education and conservation attention on a select number of species.

The observation that zoos keep mostly large-bodied vertebrates and less-threatened species is not new. Balmford, Mace & Leader-Williams (1996), and more recently Pritchard et al., (2012) and Conde et al., (2011b, 2013), have demonstrated this using different sets of data. However, the study by Martin et al. (2014) makes this point more robustly and confirms, at least for mammal and bird species, that they are larger, more widely distributed and less threatened than their close relatives not held in zoos. Zoos, therefore, house species of lesser conservation priority. Although Martin et al.'s (2014) analysis adds ‘grist to the mill’ to the belief that zoos should be holding more threatened species if these institutions are to make a veritable contribution to species conservation, the jury is still out whether just increasing representation of endangerment in their collections is the way forward.

This is so because, whether we want it or not, there is a ‘natural’ tendency toward ‘charismatics’. Even other conservation-related fields, such as conservation research, suffer from taxonomic bias, subjectivity in the choice of research topics and even how resources are allocated (Clark & May, 2002). For example, conservation spending patterns and policy decisions are biased toward certain taxa, often revealing a strong connection between existing conservation policies and scientific information, research priorities and public concern (Martín-López et al., 2009). This effect is often brought about because the more threatened a taxon (at least for certain vertebrate groups), the more likely funds are to be channeled into research and conservation for that taxon. Garnett, Crowley & Balmford (2003) presented data to suggest that the direct consequence of a species reaching critically endangered or endangered status is a need for a substantial increase in the funding levels for research on that species. Spending large amounts of money on a particular priority species, however, is not the most efficient way to promote biodiversity conservation, because some of the most highly ranked species require huge conservation efforts with a small chance of success, whereas other, less-threatened species might be successfully conserved for relatively little cost (Possingham et al., 2002).

We now know, and supported numerically by Martin et al. (2014), that there is strong evidence that zoos are taxonomically biased. This occurs because species are often selected for exhibition (to which some conservation purpose may be attached later) based on personal interests (not just of the zoo director, but also of the institution). In some cases, species selection may or may not reflect certain actual or supposed values (Proença, Pereira & Vicente, 2008). Moreover, most in situ conservation work on threatened species undertaken by zoos, for example World Association of Zoos and Aquariums-branded projects, focuses on mammals, particularly on charismatic primates and carnivores, but other animal groups (e.g. amphibians and fishes) are significantly underrepresented (Gusset & Dick, 2010). This is also the case for European and North American conservation breeding programs and in situ conservation projects supported by European and North American zoos (AZA, 2014; EAZA, 2014), and also by Mexican zoos (Lascuráin et al., 2009).

Special tensions are created when conservation projects and animals' biological needs are balanced against zoos' financial and public relations imperatives. As zoos consider visitors' recreational motives to be vital to their mission and survival (Chiszar, Murphy & Iliff, 1990; Bostock, 1993; Maple, 1995), it remains unclear what trade-offs are reasonable. Mazur & Clark (2001) suggest that these management structures are also promoted internally and externally, often by forceful public relations and/or mechanisms that draw on ‘smoke and mirrors’ to promote something that is unreal. In other words, effectiveness is often measured by ‘how much’ is promoted as having been done (with phrases like ‘our zoo is here for conservation’) rather than measuring success and performance in more transparent and accountable ways.

So how do we move zoos to become beacons of conservation? Perhaps, the first barrier to overcome is to get zoos to integrate zoo conservation thinking within modern environmental problem solving. Some attempts have been made by the zoo community to give directions for zoological institutions to engage in conservation, but what may be lacking are clearer targets. Fa (2012) has suggested that zoos should focus on the more survival-compromised species, such as those listed in the Alliance for Zero Extinction (AZE, 2014). Perhaps, it is easier (or economically safer) for zoos to argue that people visit to see the charismatic fauna in their collections (either because they are large and fierce as in the case of tigers and lions, or just show-off, send-ups of people as the now ever-present meerkats) and that is what they should provide. The question is, are zoos unable to think ‘outside the box’ and strive to change the way the public engage with any animal collection, or are there unmovable visitor preferences to which the zoo has to conform to survive?

Whatever the case – and it should be resolved either way – the undeniable reality is that zoos can be effective commercial enterprises. A possible option is for zoos to determine how much emphasis (and funds) they are willing to commit to conservation. Once they do this, they can then decide whether they merely exhibit animals for education and recreation (and make money), or really get involved in direct conservation. This could mean that the animal collections of ‘direct conservation’ zoos will look different from those of ‘indirect conservation’ zoos; for example, they would develop coherent messages by exhibiting species that can change societal perceptions, and more importantly encourage adequate funding for those species needing conservation attention. But all zoos that want to achieve transparent and measureable conservation outcomes (ultimately meaning many more species conserved) will need to work together more effectively. If zoos are willing to invest in species conservation worldwide, educate the public and promote new conservation talent, the chimera that zoos are would be less an anomaly and more the norm.


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