Gina M. Ferrie

Maintaining sustainable animal populations is fundamental to zoo and aquarium missions in education, visitor engagement, entertainment, scientific advancement, public health and wellbeing, advocacy, and conservation impact. Yet, sustaining viable populations remains a persistent challenge. Small populations are inherently vulnerable to demographic and genetic challenges which threaten both individual animal welfare and population‐level goals. However, as emerging research advances our understanding of population biology, zoos and aquariums are positioned to transform how we sustain ex situ populations. This commentary highlights pressing questions facing the field today, including how to manage the size and structure of populations, integrate genomic advances and emerging technologies, build on interdisciplinary approaches, and ensure our populations have a conservation impact, as well as how we scale our advances across diverse taxa. We examine both the challenges and opportunities that will shape the future of population management in zoos and aquariums.

Low reproductive success rates can be a common problem for threatened species, impacting population viability and limiting recovery potential. Reproductive success can also be particularly low in populations that are managed ex‐situ. This can pose a challenge for threatened species recovery programmes because high reproductive success rates are often required to provide offspring for wild releases while ensuring population viability. Understanding the underlying causes of low reproductive success rates in ex‐situ populations of threatened species is therefore essential so that management programmes can optimise species' recovery potential. Here, we quantify rates of egg viability (i.e., indicating fertility and/or early embryo mortality) and total hatching success in the Extinct in the Wild sihek (Guam kingfisher, Todiramphus cinnamominus ). Using Bayesian generalised linear mixed models, we investigate effects of parental age, parental inbreeding coefficient ( f ), egg f and incubation method on egg viability and hatching success of viable eggs. We find that the sihek population has extremely low egg viability rates (~48% ± 2.15%, N = 304/635) and total egg‐hatching success rates (~30% ± 1.82% SE 190/635) compared to other threatened and non‐threatened bird species, both ex‐situ and in the wild. We find that increased paternal age and f are key drivers of decreased egg viability. In contrast, increased maternal age and use of artificial incubation are important contributors to decreased egg‐hatching success. Our results are particularly pertinent given current active recovery planning for sihek, which may require increased offspring production for wild releases. Furthermore, our results suggest that, in closed ex‐situ populations where f inevitably increases across generations such that at a given time point older aged individuals may have lower f , there is a need for breeding recommendations to quantitively and systematically balance genetic considerations with species' biological limitations such as reproductive senescence to meet recovery programme goals.

Due to their potential impact on population growth, many studies have investigated factors affecting infant survival in mammal populations under human care. Here we used more than 30 years of Association of Zoos and Aquariums (AZA) studbook data and contraception data from the AZA Reproductive Management Center, along with logistic regression models, to investigate which factors affect infant survival in four Eulemur species managed as Species Survival Plans® in AZA. Across species, infant survival to 1 month ranged from 65% to 78%. Previous experience producing surviving offspring was positively correlated to infant survival in collared (Eulemur collaris), crowned (Eulemur coronatus), and mongoose (Eulemur mongoz) lemurs. Both dam age and previous use of contraception were negatively correlated to infant survival for collared lemurs, though our results suggest the latter may be confounded with other factors. Blue‐eyed black lemurs (Eulemur flavifrons) were affected by birth location, suggesting differences in husbandry that may affect infant survival. These results can be used to assist in reproductive planning or to anticipate the likelihood of breeding success. Population managers may also be able to focus their reproductive planning on younger dams or those with previous experience to predict successful births. Future studies should seek to determine what aspects of previous dam success are most important to infant survival, investigate sire‐related factors, and examine factors related to cause of death in infants that may lead to differential survival. Our hope is to present a framework that may be useful for investigating infant survival in other mammal species' breeding programs.

Understanding how visitors spend time in zoo exhibits is important as zoological facilities work to enhance visitor experience and conservation education outcomes. We explored a variety of factors we hypothesized would influence visitor stay times in two aviaries at Disney's Animal Kingdom®. Within these aviaries, visitors could utilize educational materials, listen to staff‐led demonstrations, or talks, view animal training sessions, or speak directly with animal care or education staff. We observed visitors and recorded the opportunities they utilized in the exhibit. Visitors to either aviary who conversed with exhibit‐specific staff stayed between 67% and 89% longer than visitors who did not. In addition, visitors who used a bird guide while in either aviary stayed between 59% and 82% longer than those who did not. Those who listened to an animal care talk or engaged with a staff‐led demonstration stayed between 50% and 68% longer than those who did not have the option to participate in such activities. This study provides insight into how exhibit offerings can influence visitor behavior. Implementing strategies used in this study to increase visitors' time in an exhibit may enhance visitor experience and improve learning outcomes.

People’s attitudes toward wildlife may impact their behaviors in support of conservation. We surveyed people in the United States to determine if gender, age, or visual contexts commonly seen in zoos impacted wildlife attitudes and perceptions of animals in zoos. After viewing an image of a two-toed sloth (Choloepus hoffmanni) or reticulated python (Malayopython reticulatus) in one of six different contexts, respondents indicated their agreement with statements designed to reveal their wildlife attitudes. We categorized attitude types, determined factors influencing attitudes, and investigated perceptions of animals in zoos. Analyses revealed both positive and negative wildlife attitudes. Attitudes were not influenced by the context in which animals were portrayed but were highly impacted by gender and age. Similar factors influenced perceptions of animals in zoos. Zoological facilities should consider how attitudes are shaped by gender and age when designing animal exhibits, educational programs, and media offerings to promote conservation mindedness.

Science‐based management confers a variety of benefits to wildlife populations that are cooperatively managed by zoos and aquariums, including those managed through the Association of Zoos and Aquariums. Briefly, when management strategies are successful, they result in reproductively robust populations that better retain genetic diversity and limit inbreeding than unmanaged populations. Although the benefits of demographic and genetic management have been well documented throughout both the scientific and popular literature, it has also been established that the majority of managed populations in zoos and aquariums are not meeting the minimum criteria believed to convey long‐term biological viability. For most of these populations, an inability to meet viability criteria is not an inherent failure of how cooperative management is implemented. Furthermore, in recent years, we have perceived that the need to meet specific viability goals sometimes has obscured the benefits that these populations receive from rigorous, science‐based management. To better clarify the conversation surrounding population viability in zoos and aquariums, we seek to decouple viability measures and how they predict population persistence from the benefits conferred to populations through science‐based management. A primary goal of population management is to facilitate the persistence of priority species for longer than would be expected if no such management were implemented. Although current viability measures and future projections of viability are important tools for assessing the likelihood of population persistence, they are not indicators of which populations may most benefit from science‐based management. Here, we review the history and purpose of applying science‐based management to zoo and aquarium populations, describe measures of population viability and caution against confusing those measures of viability with population management goals or long‐term population sustainability, and clearly articulate the benefits conferred to zoo and aquarium populations by science‐based management.

Many articles have shown the benefits of operant conditioning training techniques in the care and welfare of several species of nonhuman primates; however, the information regarding their use in strepsirrhine species is scarce. We assessed the development and current status of training programs with these species in North American institutions. An online survey was distributed through members of the Association of Zoos and Aquariums using a multiple-choice format. We collected information related to training program details; animals, behaviors, and techniques; the evaluation process; and the impact of training. Seventy-one organizations completed the survey, with the results showing that 97% of respondents trained their strepsirrhines with the main objective of husbandry and veterinary care (around 80%). Sixty-eight percent of organizations did not report any risk in training these species. The benefits reported include increases in positive human–animal interactions (97%), psychological well-being (88%), and staff awareness of animal behaviors (90%). However, a multi-dimensional approach to measure the efficacy of training could provide a deeper understanding of its impact on the welfare of strepsirrhine primates. We hope that the data offered in this survey can help in this future assessment.

Despite the fact that saddle‐billed storks (SBS) are housed in zoos around the world, few successful hatches have been recorded. At Disney's Animal Kingdom® we conducted observations on two pairs of SBS during multiple reproductive periods to assess the relative strength of their pair‐bonds and their reproductive success. We accomplished this through observations of rates of social behaviors, such as wing displays and aggression, rates of nest construction, time on and near the nest, and egg production. We determined that one pair was more successful than the other because it produced and incubated eggs during all breeding seasons. We found that the male from this more successful pairing displayed higher rates of nest presence, nest construction, and time on the nest than all other individuals. The more successful pairing also spent more time in close proximity than the less successful pair. During incubation, the male and female from the more successful pair spent similar amounts of time at the nest and incubating the eggs, but this pair never successfully hatched an egg during our study period. Ultimately, our results suggest that the pair‐bond between the more successful pair was stronger than that of the other pair because they spent more time in close proximity and performed higher rates of nesting behaviors. This study highlights the lack of understanding of the factors that lead to successful SBS pairings in zoos, and emphasizes the need for future studies of their nesting behavior and pair compatibility to increase reproductive success.

Inbreeding can depress individuals’ fitness traits and reduce population viability. However, studies that directly translate inbreeding depression on fitness traits into consequences for population viability, and further, into consequences for management choices, are lacking. Here, we estimated impacts of inbreeding depression (B, lethal equivalents) across life-history stages for an extinct-in-the-wild species, the sihek (Guam kingfisher, Todiramphus cinnamominus). We then projected population growth under different management alternatives with our B estimates incorporated, as well as without inbreeding depression (B = 0) or with a conventional default B. We found that inbreeding depression severely impacted multiple life-history stages, and directly translated into an effect on population viability under management alternatives. Simulations including our B estimates indicated rapid population decline, whereas projections without inbreeding depression or with default B suggested very gradual population decline. Further, our results demonstrate that incorporation of B across life-history stages can influence management decisions, as projections with our B estimates suggested a need to switch to increased breeding management to avoid species extinction and support wild releases. Our results demonstrate that magnitude of B across life-history stages can translate into demographic consequences, such that incorporation of multiple life-stage B into population models can be important for informed conservation management decision-making.

Incorporating technology with research is becoming increasingly important to enhance animal welfare in zoological settings. Video technology is used in the management of avian populations to facilitate efficient information collection on aspects of avian reproduction that are impractical or impossible to obtain through direct observation. Disney's Animal Kingdom^® maintains a successful breeding colony of Northern carmine bee-eaters. This African species is a cavity nester, making their nesting behavior difficult to study and manage in an ex situ setting. After initial research focused on developing a suitable nesting environment, our goal was to continue developing methods to improve reproductive success and increase likelihood of chicks fledging. We installed infrared bullet cameras in five nest boxes and connected them to a digital video recording system, with data recorded continuously through the breeding season. We then scored and summarized nesting behaviors. Using remote video methods of observation provided much insight into the behavior of the birds in the colony's nest boxes. We observed aggression between birds during the egg-laying period, and therefore immediately removed all of the eggs for artificial incubation which completely eliminated egg breakage. We also used observations of adult feeding behavior to refine chick hand-rearing diet and practices. Although many video recording configurations have been summarized and evaluated in various reviews, we found success with the digital video recorder and infrared cameras described here. Applying emerging technologies to cavity nesting avian species is a necessary addition to improving management in and sustainability of zoo avian populations. Zoo Biol. 35:76–82, 2016.