Association Of Zoos And Aquariums Research Articles

Male elephant management in AZA institutions: Current status and priorities for the future.

Asian elephant (Elephas maximus) and African savanna elephant (Loxodonta africana) populations collectively managed by ex-situ facilities accredited by the Association of Zoos and Aquariums (AZA)face sustainability challenges. Among the priorities to strengthen animal wellbeing and population sustainability is male elephant management. We conducted a survey of AZA facilities currently housing male elephants to assess the status, challenges, and priorities in three areas of male elephant management: musth, socialization, and semen collection. Surveys were administered to elephant care teams at AZA-accredited institutions between November 2022 and February 2023, and we received responses from 34 institutions (91.9% of AZA-accredited facilities holding adult male elephants), housing 32 adult male Asians and 26 adult male Africans. Most facilities prioritized breeding and male socialization over musth management and semen collection (although most facilities acknowledged that all these efforts are important), citing leadership support and staffing as most important to achieve male management goals. Behaviors most commonly accompanying musth included reduced appetite, difficulty training or shifting, human-directed aggression, and interest in females. Musth timing was variable between males and facilities. Most males were well-socialized with females and/or other males, though elephant compatibility and facility design were limiting factors in managing socialization. Although 60.6% of facilities collected semen or were training for semen collection, very few male elephants could reliably provide viable semen samples, challenging assisted reproductive efforts that could bolster population sustainability in both species. Together, our results provide a better understanding of the state of male elephant management, offering specific areas deserving of research and development to enhance wellbeing and sustainability.

What Types of Animals Should Be in the Future Zoo? Thoughts from United States Residents and Zoo and Aquarium Staff

Humans are biased in their preferences for animals, and this may impact the composition of zoological collections. We assessed which kinds of animals the public and zoo professionals want to preserve in zoos for the future and analyzed these lists for previously identified biases and agreement across surveyed groups. We also characterized agreement among the surveyed groups on the roles of zoos and the composition of animal collections. We surveyed people who live in the United States, members of the Association of Zoos and Aquariums (AZA), and AZA zoo and aquarium directors. There was agreement among surveyed groups on the roles of zoos, though some differences existed. Zoo professionals and the public generally agreed on the emphasis on various categories of animals for zoo collections, though some differences were noted. We found evidence of bias towards mammals, charismatic megafauna, and felids across all surveyed groups. Agreement was high between AZA members and directors and moderate between zoo professionals and the public. These results indicate that these groups are generally in agreement about the roles of zoos, how they should compose their animal collections, and what animal species, in particular, should be kept in zoos for the future, allowing zoos to compose their collections to maximize delivery on their mission goals as well as address the preferences of the public.

Observations of reproductive behaviors in the Critically Endangered bowmouth guitarfish Rhina ancylostoma

Wedgefishes, family Rhinidae, are collectively identified as one of the most threatened groups of chondrichthyan fishes globally by the International Union for Conservation of Nature’s (IUCN) Red List of Threatened Species. Within the family Rhinidae, bowmouth guitarfish Rhina ancylostoma have been designated by the IUCN as Critically Endangered since 2018. Bowmouth guitarfish were first introduced to the Association of Zoos and Aquariums (AZA) in 2005 when the Newport Aquarium, Newport, KY, USA, acquired a single female. In 2007, a male bowmouth guitarfish was added into the collection with the goal of establishing an institutional breeding program and to generate foundational knowledge for future breeding programs. This study presents an ethogram of mating behaviors exhibited by a mixed sex group of bowmouth guitarfish using behavioral observations from December 2017 through August 2022. The observed interactions between male and female bowmouth guitarfish led to the identification of 5 male reproductive behaviors: hovering, chasing, wrapping up, flipping/rolling, and copulation. These 5 behaviors were directly linked with successful reproduction, e.g. active breeding and live parturition, in the imperiled species R. ancylostoma. The breeding behavioral knowledge presented within this study provides the first step to a viable breeding program, a critical tool for conserving wild populations.

Infant survival is significantly impacted by dam- and management-related factors in zoo-managed Eulemur populations.

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.

Wild origins and mitochondrial genetic diversity of Angolan Colobus monkeys (Colobus angolensis) in AZA-accredited zoos and its implications for ex situ population management.

Across zoo's accredited by the Association of Zoos and Aquariums(AZA), species are typically managed as a single population to retain 90% of the founding members' gene diversity. Often, little is known about the specific geographic origins of the founders or how representative the ex situ population's genetic diversity is of the wild population. This study uses mitochondrial DNA (mtDNA) sequencing to investigate haplotype diversity and geographic female founder origin of the AZA-managed Angolan colobus (Colobus angolensis) monkey population. We obtained fecal samples from individuals closely related to founder animals at five zoos and found four haplotypes among 23 individuals. Analyzed together with wild C. angolensis haplotypes, we found two haplotypes identical to those found in Tanzanian populations: one haplotype, possessed by 13 individuals (descended from three founders), matched an East Usambara Mountains haplotype, while the other, possessed by seven individuals (from four founders), matched a haplotype found in both the South Pare Mountains and Rufiji River. Two haplotypes were not detected in wild populations but were closely related to haplotypes found in the Rufiji River (one individual descended from one founder) and Shimoni, Kenya (two individuals descended from one founder) populations, suggesting nearby origins. Thus, the AZA-managed population of Angolan colobus likely originated from several localities, but all have mtDNA lineages associated with the subspecies C. a. palliatus, a Vulnerable subspecies. Examining founders' mtDNA haplotypes may be a useful addition to the zoo population management toolkit to help improve breeding recommendations by identifying individuals with rare haplotypes and revealing likely kinship among founders.

RETROSPECTIVE ANALYSIS OF MORTALITY CAUSES IN MANAGED KIRK'S DIK-DIKS (MADOQUA KIRKII) IN NORTH AMERICA FROM 1988 to 2019.

Kirk's dik-diks (Madoqua kirkii) are the most common dik-dik species managed in North American zoological institutions, but their numbers are declining at a concerning rate, with less than 40 individuals currently housed in accredited institutions. This retrospective study reports the causes of mortality in Kirk's dik-diks in North American zoological institutions from 1988 to 2019. Out of 15 institutions accredited by the Association of Zoos and Aquariums (AZA) currently housing Kirk's dik-diks, nine contributed to this study (60% participation). Eighty-four necropsy records were reviewed to determine the primary affected body system and etiological cause of death across and within age categories. Neonatal death (prior to 1 mon of age) was most common (38.1%), followed by death in adults (29.8%), geriatric animals (19.0%), and juveniles (13.1%). As a whole population, causes of death by body system were multisystemic (47.6%), musculoskeletal (15.5%), respiratory (8.3%), and digestive (8.3%). Neonatal complications accounted for 50.0% of all deaths in animals prior to 1 mon of age. In juveniles, a nutritional cause of death was most common (27.3%) and significantly higher compared to measures of this cause within other age categories. In adults, metabolic etiologies and trauma each accounted for 28.0% of deaths. Degenerative etiologies were most common in geriatric individuals, representing 31.3% of the deaths. Death from infectious disease was found across all ages, representing 11.9% of all mortalities. Results from this study provide a baseline reference for this species and may aid clinicians in decision-making as it relates to the medical care and management of this species during different life stages.

Does Accreditation by the Association of Zoos and Aquariums Correlate with Animal Welfare Act Compliance?

ABSTRACT The Association of Zoos and Aquariums (AZA) promotes itself as the “gold standard” for animal welfare in zoos and aquariums; however, no objective evaluation of this claim has been performed. As the only statute providing protection to individual animals in the United States, the Animal Welfare Act (AWA) also seeks to assure animal welfare at facilities exhibiting animals to the public. In this study, the incidences of AWA noncompliant items (NCIs) at AZA-accredited facilities were evaluated and compared to non-accredited facilities licensed as exhibitors by the United States Department of Agriculture (USDA). Based on our analysis, non-accredited exhibitors had significantly more total NCIs than AZA-accredited facilities, and non-accredited facilities also had more NCIs related to improper veterinary care, animal husbandry, and record-keeping, but not with respect to personnel qualifications. Additionally, accreditation status and number of regulated species were significant predictors of the number of NCIs. This study revealed that AZA accreditation is correlated with improved compliance with the AWA and perhaps enhanced animal welfare.

Variation in the PRNP gene of Pere David’s deer (Elaphurus davidianus) may impact genetic vulnerability to chronic wasting disease

Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy caused by prions that has spread across cervid species in North America since the 1960s and has recently been detected in Eurasian cervids. The Association of Zoos and Aquariums (AZA) considers CWD to be of major concern for cervids in AZA-accredited facilities because of the indirect transmission risk of the disease and the impact of CWD regulatory protocols on captive breeding programs. Vulnerability to CWD is affected by variation in the PRNP gene that encodes the prion protein. We therefore sequenced PRNP in Pere David’s deer (Elaphurus davidianus), a species that was extinct in the wild for more than a century and descends from ca. 11 founders. In 27 individuals, we detected two PRNP haplotypes, designated Elad1 (51 of 54 sequences) and Elad2 (3 of 54 sequences). The two haplotypes are separated by four single nucleotide polymorphisms (SNPs), three of which are non-synonymous. Both Elad1 and Elad2 have polymorphisms that in other cervid taxa are associated with reduced vulnerability to CWD. The two haplotypes are more similar in sequence to PRNP in other cervids than to each other. This suggests that PRNP in cervids may have been under long-term balancing selection, as has been shown for PRNP in non-cervid taxa, and which could account for the presence of multiple haplotypes among founders. There may be a fitness benefit in maintaining both PRNP haplotypes in the species because variation in the prion protein amino acid sequence can limit transmission of CWD.

Increasing AZA-Accredited Zoo and Aquarium Engagement in Conservation

Conservation should be the higher purpose of any modern zoological facility and has consistently been a required element of accreditation by the Association of Zoos and Aquariums (AZA). Each year, AZA-accredited zoos and aquariums collectively commit considerable resources to conservation around the world, exceeding 150 million USD annually since 2011 and exceeding 231 million USD in 2019. Furthermore, with 195 million people visiting AZA-accredited zoos and aquariums each year, there is enormous opportunity to connect people to nature and engage them as agents of change. As AZA facilities continue to prioritize conservation-driven missions, their participation in field conservation has increased greatly. AZA SAFE: Saving Animals From Extinction (SAFE)®was established in 2014 to encourage greater collaboration of AZA members and their field partners to save species. The SAFE framework is dedicated to species recovery and based on conservation best practices. SAFE species programs develop 3-year action plans that build on established recovery plans, evaluate impact, and combine AZA facilities and visitors to increase resources for research, public engagement, communications, and conservation funding. Here we share preliminary outcomes of the SAFE program as they relate to programmatic measures of success to determine whether the framework 1) is useful for the AZA membership as measured by engagement and participation, and 2) increases conservation activity on behalf of targeted species as measured by the number of facilities supporting a species' conservation and financial investment. In this analysis we utilized data supported by the AZA Annual Report for Conservation and Science (ARCS) to demonstrate benefits of the SAFE framework and provide insights into future strategies to enhance conservation impact.

Utilizing Camera Traps, Closed Circuit Cameras and Behavior Observation Software to Monitor Activity Budgets, Habitat Use, and Social Interactions of Zoo-Housed Asian Elephants (Elephus maximus).

Simple SummaryZoological institutions place strong emphasis on monitoring the welfare of individual animals in their care. Long-term behavior data can be integrated into zoological management to allow for adjustments on a continuous basis as animals respond over time to social, environmental, or physical changes. Behavioral observations conducted for two years on one male and six female Asian elephants (Elephas maximus) using Zoo Monitor, a closed-circuit camera system, and camera traps revealed individual activity budgets, habitat use and social interactions in ways beyond use of these tools in isolation. This multi-tool approach provides a broader assessment of individual welfare, which can lead to better management of elephants, and potentially other species, in zoological settings.Accredited zoos and aquariums value superior animal husbandry and strive to ensure that the physical, psychological, and social needs of animals are met. In North America, the Association of Zoos and Aquariums (AZA) relies on species-specific standards to ensure facilities provide the best care for collection animals. The AZA also makes explicit recommendations for long-term monitoring of welfare. Data collected through behavioral observations can be used to modify management as animals respond over time to social, environmental, or physical changes. In long-lived, social species like elephants, it is particularly important to document herd dynamics, calf development, geriatric health, and social bonds throughout their lifetimes. The Smithsonian’s National Zoological Park housed one male and six female Asian elephants in dynamic social groupings. Behavioral observations were conducted on all elephants for two years using two methods involving ZooMonitor, closed circuit cameras, and camera traps. The goal was to compare how these two methods function to provide individual activity budgets, habitat use, and social interactions. Methodologies such as these, alone or in combination, have the potential to produce valuable data about potential changes in welfare over time in a zoological setting and can be performed either by staff or volunteers with high reliability.

Conservation medicine and One Health in zoos: Scope, obstacles, and unrecognized potential.

Zoo veterinarians and allied professionals have been contributing to conservation medicine (CM) and One Health (OH) activities for more than two decades. Although the Association of Zoos and Aquariums (AZA) considers conservation a key part of its mission, little published material exists about the extent of AZA work in CM/OH or the challenges and opportunities associated with these endeavors. To better understand the current scope of CM/OH in zoos, we surveyed 53 AZA-accredited institutions from April through October of 2016. We obtained information on CM/OH infrastructure, support for expansion in this area, and strategies to overcome perceived obstacles hindering CM/OH from becoming a core AZA activity. Survey results revealed that while most zoos favor greater investment in CM/OH programs, awareness, and understanding of CM/OH across the broader zoo community and public is lacking. The majority of respondents stated that overcoming this challenge is paramount to attaining support for CM/OH initiatives. In spite of these obstacles, survey respondents highlighted many positive developments in CM/OH. We found that 84% of zoos surveyed are actively engaged in CM/OH activities, and 12% house formal CM/OH programs. Another 8% of respondents said their institutions were developing CM/OH programs. Perhaps most noteworthy, we found that zoo size did not have a significant bearing on the financial amount allocated toward an institution's CM/OH activities. This suggests that all zoos, regardless of size, can make meaningful contributions to the growing movement of CM/OH and help redefine the role of zoos within this movement.

Ovarian cyclicity and prolactin status of African elephants (Loxodonta africana) in North American zoos may be influenced by life experience and individual temperament

Hyperprolactinemia is an endocrine disorder associated with infertility in many species, including elephants. In a recent survey of zoos accredited by the Association of Zoos and Aquariums (AZA), over half of African elephant females (N = 101) were not cycling normally, 30% of which exhibited hyperprolactinemia. We examined whether life experience and temperament predict ovarian cyclicity and circulating prolactin status in individual African elephant females. We hypothesized that, similar to humans, acyclicity and hyperprolactinemia in elephants will be associated with an apprehensive or fearful, anxious temperament, and an increased number of potentially challenging life events (transfers, deaths and births). Ninety-five adult African elephant females housed at 37 AZA institutions were included in this study. Blood samples were collected twice a month for 1 year to determine ovarian cycle (cycling, n = 44; irregular, n = 13; non-cycling, n = 38) and prolactin (normal, n = 44; low; n = 23; high; n = 28) status. Keeper ratings on a 6-point scale were obtained on 32 temperament traits in 85 of these elephants. We determined that giving birth and being exposed to herd mates entering the facility were positively associated with normal ovarian cycle and prolactin profiles. By contrast, age, serum cortisol, and an increased number of herd mates leaving a facility were negatively associated with both. Contrary to our hypothesis, hyperprolactinemia was associated with a popular and caring temperament rating, whereas consistently low prolactin was associated with a fearful, apprehensive temperament. These findings indicate that pituitary-ovarian function may be impacted by life history (cyclicity) and temperament (prolactin), which should be taken into consideration when making management decisions.

ESTABLISHMENT OF ACUTE-PHASE PROTEIN AND SERUM PROTEIN ELECTROPHORESIS PRELIMINARY REFERENCE VALUES FOR PRONGHORN (ANTILOCAPRA AMERICANA).

Pronghorn (Antilocapra americana) are native to western North America and are found in 24 Association of Zoos and Aquariums (AZA)-accredited institutions. Acute-phase proteins (APP) are a broad class of proteins that are stimulated in response to inflammation and have been shown to be a sensitive measure of inflammation in equids and ruminants. In this study, blood samples from clinically normal free-ranging and captive populations of pronghorn were analyzed using assays for protein electrophoresis (EPH) and APP, including serum amyloid A (SAA) and haptoglobin (HP), to develop preliminary ranges to gauge potential differences between these populations. Additional samples were taken from clinically abnormal captive pronghorn with facial abscesses. By EPH measurements, albumin: globulin ratio mean and SE were significantly different (P <0.05) with 1.02 (0.08) for captive populations and 1.91 (0.05) for free-ranging populations. Total protein mean and SE were significantly different (P <0.05) for captive and free-ranging populations, respectively 5.6 (0.3) g/dl and 6.9 (0.1) g/dl. Mean and SD of SAA for captive pronghorn were 1.4 (3.2) mg/L, and were significantly different from the free-ranging population, which was below the limits of detection for (P <0.05). There was no difference in HP levels between these groups. In a case study of a pronghorn with facial abscesses, elevated levels of HP, but not SAA, suggested that HP maybe useful in certain disease states. Future studies should explore the use of these biomarkers as tools to monitor general health, prognosis, and subclinical disease.

Challenges and solutions: An analysis of community-reported needs of AZA collaboratively managed animal populations.

Zoos and aquariums accredited by the Association of Zoos and Aquariums (AZA) cooperatively manage Species Survival Plan(R) (SSP) Program populations to maximize genetic and demographic health and work toward long-term population sustainability. However, recent analyses suggest that only a minority of populations were projected to maintain their sustainability goals over 100 years. As one of the initial steps in addressing this concern, the AZA collaborated with hundreds of members of the zoo and aquarium community to develop the SSP Sustainability Database, a repository of quantitative and qualitative data on SSP Program challenges, population data, and management needs. A goal of this initiative was to identify the most critical needs across taxa and provide AZA-accredited facilities a mechanism to align institutional resources with SSP Program priorities, thus facilitating strategic decision-making for population sustainability at all levels of population management. Four types of critical SSP population needs emerged as the most common: additional spaces, optimized and standardized husbandry practices, the incorporation of new individuals into the population (importation), and improved breeding and transfer recommendation fulfillment. Patterns and trends in these critical needs varied across taxa and ex situ extinction risk (proxied by population management designation). The AZA community can apply these findings and proactively engage in opportunities to enhance SSP Program population sustainability through strategic, collaborative group action.

Uncovering challenges to sustainability of AZA Animal Programs by evaluating the outcomes of breeding and transfer recommendations with PMCTrack.

The Association of Zoos and Aquariums (AZA) cooperatively manages Species Survival Plans® to create demographically and genetically viable populations. SSPs issue animal-specific recommendations to participating institutions via Breeding and Transfer Plans (BTPs). Fulfillment of recommendations is a crucial step in maintaining viable populations, but there have been no comprehensive evaluations of the system. Using PMCTrack, a database of over 110,000 breeding and transfer recommendations issued from over 200 SSPs from 1999 to 2013, we analyzed fulfillment of recommendations. Action-based recommendations had lower rates: Breed With recommendations were fulfilled at a rate of 20.0% before the next BTP, Send To at 56.8%, Do Not Breed at 95.7%, and Hold at 92.9%. We used generalized (logistic) mixed-effects model regressions to evaluate the impact of biological, management, and programmatic factors on fulfillment rates. For all recommendation types, there was significant variation in fulfillment among Programs and within Programs among BTPs. Out of 80 potential hypothesized fixed effects (20 factors * 4 recommendation types), only 20 effects (25%) were statistically significant. Rates were strongly influenced by temporal variables, generally increasing over time and as programs get older. Notably, the amount of time between BTPs was the only variable that significantly predicted fulfillment of all recommendation types. Many additional factors at the individual animal and institutional level may effect fulfillment rates and should be the subject of future analysis. Our results illustrate the utility of PMCTrack and indicate that improvements to the viability of SSPs will need to address multiple biological and management challenges.

Quantifying the contribution of zoos and aquariums to peer-reviewed scientific research

Modern zoos and aquariums aspire to contribute significantly to biodiversity conservation and research. For example, conservation research is a key accreditation criterion of the Association of Zoos and Aquariums (AZA). However, no studies to date have quantified this contribution. We assessed the research productivity of 228 AZA members using scientific publications indexed in the ISI Web of Science (WoS) database between 1993 and 2013 (inclusive). AZA members published 5175 peer-reviewed manuscripts over this period, with publication output increasing over time. Most publications were in the zoology and veterinary science subject areas, and articles classified as “biodiversity conservation” by WoS averaged 7% of total publications annually. From regression analyses, AZA organizations with larger financial assets generally published more, but research-affiliated mission statements were also associated with increased publication output. A strong publication record indicates expertise and expands scientific knowledge, enhancing organizational credibility. Institutions aspiring for higher research productivity likely require a dedicated research focus and adequate institutional support through research funding and staffing. We recommend future work build on our results by exploring links between zoo and aquarium research productivity and conservation outcomes or uptake.

The evolving role of zoological parks and aquariums in migratory bird conservation.

As threats to migratory birds in the Western Hemisphere, including North America, intensify and bird populations decline, there is a growing interest among zoo biologists in the conservation and management of these taxa. The purpose of this article is to explore the role that Association of Zoos and Aquariums (AZA)-accredited zoos and aquariums either are playing or could play in the conservation and management of migratory birds. Topics explored include: (1) Public education and advocacy; (2) Captive breeding and reintroduction; (3) In situ conservation; (4) Tracking and monitoring; (5) Research/technology development; and (6) Sustainability/green practices; and (7) Partnerships. Zoos and aquariums could play an important role in increasing the public's access to understanding migratory birds and the threats they face, ultimately helping to protect these remarkable species.

Genetic tests reveal extra-pair paternity among Gentoo penguins (Pyogoscelis papua ellsworthii) at Loveland Living Planet Aquarium: Implications for ex situ colony management.

Maintenance of ex situ populations for species conservation is a collaborative effort involving multiple agencies, institutions, and individuals around the world. Gentoo penguins (Pyogoscelis papua) are one species involved in such a conservation effort, and a Species Survival Plan (SSP) has been put in place by the Association of Zoos and Aquariums (AZA) to foster their long-term sustainability. As a part of their SSP, a Breeding and Transfer Plan has been created to support interagency exchanges of specimens. These transfers are vital to the demographic health and stability of ex situ populations, as well as the maintenance of genetic diversity. In populations such as the Gentoo, where social monogamy exists, paternal inferences of offspring are usually made through observation of birds' social behavior. However, social monogamy does not guarantee reproductive monogamy. In this study, we utilize Illumina high-throughput DNA sequencing to genetically test the postulated paternity of Gentoo penguins born at Loveland Living Planet Aquarium (LLPA) in Draper, UT. While our data support the majority of the postulated relationships, we did identify two offspring that were the result of extra-pair paternity (EPP). The results of this research highlight the importance of genetic tests to validate pedigrees used in SSPs, to provide more-accurate data for the support of species conservation.

Genetic and demographic analysis of European Endangered Species Programme (EEP) and Species Survival Plan (SSP) Western lowland gorilla Gorilla gorilla gorilla populations

Since the late 1990s, European Association of Zoos and Aquaria (EAZA)‐member zoos have worked collaboratively to achieve a self‐sustaining population for gorilla through the European Endangered Species Programme (EEP). The Association of Zoos and Aquariums (AZA) in the United States has similarly worked through the Species Survival Plan (SSP). These populations are all registered in the International Studbook for the Western Lowland Gorilla Gorilla g. gorilla Savage &amp; Wyman, 1847, which is updated annually. Demographic and genetic analyses of these data are carried out to monitor population development. This paper presents the results of the genetic and demographic analysis of EAZA and AZA populations of the Western lowland gorilla Gorilla gorilla gorilla, considering the individuals registered since the beginning of the studbook (1950) until 2014, and the analyses are mainly focused on the results for both populations around the last decade. The data have been gathered from the 2014 international studbook and data registered in the Single Population Analysis and Records Keeping System (Sparks). Genetic and demographic analyses were carried out using PMx software. The results of the demographic analyses show that the EEP population is growing, demonstrating positive life parameters; for example, a finite growth rate of λ = 1·007, an instantaneous growth rate of r = 0·007 and a net reproductive rate of R0 = 1·160. However, the results of the demographic analyses for the SSP population show a general tendency for population reduction; that is, a finite growth rate of λ = 0·992, an instantaneous rate of growth rate r = −0·008 and a net reproductive rate of R0 = 0·864. When comparing the results from both populations it would appear that the application of strict breeding policies in the SSP for a few years had a noticeable impact on the SSP demographic results.

Nest location preferences in zoo-housed orangutans

Nest building is an advanced and complex activity that wild orangutans engage in, yet they do so on a daily basis and with potential safety consequences. Like their wild counterparts, zoo-housed orangutans also make nests when given adequate materials, yet comparatively little research has documented the nesting habits of captive orangutans, including potential social and environmental influences of nest site selections. We documented the night nesting behavior of six adult orangutans housed at the Smithsonian's National Zoological Park (NZP), identifying preferred nest locations and proximity to conspecifics, comparing observed patterns to those reported in a nest behavior survey of orangutan facilities throughout the Association of Zoos and Aquariums (AZA). Survey results reveal that in addition to several universal patterns of nesting behaviors, as in the wild, the sharing of night nests by captive adult orangutans occurs only rarely (2 of 31 surveyed facilities). Data collected at NZP indicate that night nearest neighbor associations among nesting conspecifics may be a useful proxy for actual nearest neighbor data taken during daytime social interactions and may offer a more feasible alternative for determining social relationships among large groups of socially housed orangutans.