Type: (Review)
Ensuring species’ survival and longevity: The role of
modern zoos
Admire Chanyandura1, & *, Amna Mana Alotaiba1,
Hessa Ahmed Alqahtani1, Mouza Mubarak Alhajeri1
1. Al Ain Zoo PO BOX
1204, Al Ain, Abu Dhabi, United Arab Emirates
* Corresponding author: Chanyandura, A.; chanyandura.admire@zapia.adgov.gov.ae
Abstract: Global animal biodiversity is increasingly threatened, underscoring the critical role of modern zoos as institutions for ex-situ conservation. Zoos provide insurance populations for endangered species, supporting biodiversity through improved management, veterinary care, and habitat enrichment. This review synthesizes 213 peer-reviewed articles, reports, and case studies to evaluate developments in zoo practices that enhance animal welfare and longevity. Evidence shows that animals in managed care often live longer than their wild counterparts, with extended lifespans enabling increased reproductive opportunities, maintaining genetic diversity, and supporting sustainable breeding programs. Advances in assisted reproductive technologies, studbook management, and specialized geriatric care further contribute to population viability. Environmental enrichment and careful management of social structures improve both psychological and physical health, while veterinary interventions mitigate disease, stress, and age-related disorders. Despite these achievements, challenges remain, including replicating natural habitats, minimizing stress, and sustaining behavioral and genetic diversity. Collaborative international efforts and ongoing research are crucial for refining husbandry practices and maximizing conservation outcomes. By integrating scientific study, veterinary expertise, and enrichment programs, modern zoos have become centers of conservation excellence. Promoting longevity in captive populations not only enhances animal welfare but also strengthens global biodiversity strategies, reaffirming zoos’ pivotal role in the long-term survival of endangered species.
Keywords: ex-situ,
endangered species, viability, longevity, biodiversity, wildlife reintroduction,
managed care
Article Info.
Submitted: 22-10-2025; Revised:
11-12-2025; Accepted:
12-12-2025; Online:
23-12-2025
Cite as: Chanyandura, A., Alotaiba, A.N., Alqahtani, H.A., Alhajeri, M.M (2025). Ensuring species longevity and survival: The role of modern zoos. Animal reports, 1(2): 145-168. https://doi.org/10.64636/ar.34
This
work © 2025 by Author(s) is licensed under CC BY 4.0
Zoos have long been recognized
as important institutions in the protection of endangered species through ex-situ
management programs (Farhadinia et
al., 2020; Correia et al., 2024; Mahanayak, 2024; Gupta et al., 2025; Schaffer
et al., 2025). As human-induced threats such as habitat loss,
poaching (Chanyandura et al.,
2021), and climate change continues to imperil species globally (Fischer, 2022;
Prakash & Verma, 2022; Tapale, 2024). Zoos provide a controlled environment where endangered
species can be cared for, bred, conserved, and preserved (Robovský et al.,
2020; Browning & Veit, 2024; Sithole et al., 2024). Ex-situ conservation, in which species are maintained
outside their natural habitat, serves as an important safeguard in ensuring the
survival of species that are at risk of extinction (Uddin, 2015; McGowan
et al., 2017; Breithoff & Harrison, 2020; Keulartz, 2023). Continued research and expertise building by thousands
of zoo staff worldwide continually advance understanding of animal, population,
and ecosystem management (Tidiere et al.,
2016; Spooner et al., 2023; Browning & Veit, 2024; Scherer et al., 2024). The longevity of animals kept in zoos is a critical
component in maintaining sustainable populations of threatened species (Lees & Wilcken,
2009; Tidiere et al., 2016; Shilovsky et al., 2022; Kitchener, 2023). Age-specific mortality in zoos has declined over
time due to improved husbandry measures, notably in recent years, and this trend
is evident regardless of a species' life cycle approach. (Roller et al., 2021;
de Visser et al., 2022; Scherer et al., 2024). A prolonged lifespan allows for longer reproductive
periods, increased opportunities for genetic diversity, and more sustainable breeding
programs (Holt & Comizzoli,
2022; Nadachowska‐Brzyska et al., 2022; Salgotra & Chauhan, 2023). The concepts of longevity (longest lived) and
life expectancy (typical age at death) are common demographic parameters that provide
insight into a population (De Silva & Leimgruber,
2019; Chishty et al., 2022; Nigri et al., 2022; Roslia et al., 2023). However, there is a need to continually address
issues such as overseeing breeding programs, ensuring genetic diversity, and providing
the appropriate care to promote longevity. Zoos also aim to maintain viable ex-situ
insurance populations of endangered species that can be used for reintroduction
to the wild (Farhadinia et
al., 2020; Keulartz, 2023; Mahanayak, 2024; Staerk et al., 2024; Mastromonaco
et al., 2025). Zoos provide opportunities for researchers to
expand their skills in a wide range of fields, including basic zoology, applied
husbandry, community participation (Sithole et al.,
2024) and molecular biology (Brando & Gjerris,
2022; Hochadel, 2022; Espinosa Garcia-San Roman et al., 2023; Chavez et al., 2025). This research examines the factors that influence
the longevity of zoo animals, emphasizing the necessity of well-managed zoo populations
as insurance for endangered species.
This review focused on
the role of zoos in animal longevity worldwide. Data were
extracted from published literature, reports, and websites. To create a complete and accurate overview of current
knowledge, a systematic review was conducted guided by PRISMA protocols (Preferred
Reporting Items for Systematic Reviews and Meta-Analyses) (Ballou et al.,
2010; Roller et al., 2021; Larsen et al., 2024) of peer-reviewed journal articles, institutional
reports, and case studies on animal longevity and ex-situ conservation in zoos (Naruka & Reddy,
2023; McCreesh et al., 2024). The PRISMA protocol provided a structured framework
for conducting a systematic review, it ensured rigor, transparency, and replicability.
The PRISMA protocol components included: 1. Identification – Systematic searching
of multiple databases and repositories (peer-reviewed journals, grey literature,
reports, archives) using predefined keywords and inclusion criteria. 2. Screening
– Removing duplicates, followed by title and abstract screening to exclude irrelevant
studies. 3. Eligibility – Full-text review of the remaining records against inclusion
and exclusion criteria (e.g., timeframe, geography, thematic relevance). 4. Inclusion
– Final set of studies and documents retained for qualitative and/or quantitative
synthesis. 5. Documentation – A PRISMA flow diagram is used to record the number
of records identified, screened, excluded, and included, providing a transparent
audit trail. A comprehensive search was conducted across various
academic databases, including Web of Science, Scopus, PubMed, JSTOR,
ScienceDirect, and Google Scholar (Gusenbauer & Haddaway, 2020; Levine-Clark & Gil, 2021; Ng et al.,
2024).
The search terms included "animal longevity,"
"zoo management," "ex-situ conservation," "population viability,"
and "species survival." The analysis focused on programs
investigating factors that enhance longevity,
including veterinary care, environmental enrichment, breeding programs, and managing
genetic diversity in accredited zoos. Relevant datasets were extracted from
the Species 360 Zoological Management System (ZIMS), which serves as a global repository
of zoo and aquarium records (Roeder et al., 2024;
De Bont, 2025).
Grey literature from
reputable conservation organizations and international zoo associations, like AZA
(Association of Zoos and Aquariums), World Association of Zoos and Aquariums (WAZA),
Association of Zoos and Aquariums (AZA), and European Association of Zoos and Aquaria
(EAZA) were also included in our review. These documents provided valuable insights into real-world practices and
evolving management strategies. To ensure relevance, scientific quality, and their
contribution to understanding how improved longevity helps support sustainable,
genetically diverse populations, a wide range of sources was assessed. The final
collection of literature was then organized thematically to highlight key trends,
challenges, and evidence-based practices that contribute to the success of ex-situ
conservation programs focused on ensuring species survival and longevity.
While certain studies may have been excluded due to search
limitations, publication in lesser-known journals, or lack of subsequent citations,
the resulting article collection remains reasonably comprehensive. Out of the 298 papers that were sourced, 213 were
finally selected since they were more relevant to the study's primary issues about
animal longevity. The key topics covered are ex-situ conservation and longevity, research and development in zoos,
and veterinary care and longevity.
Ex-situ populations provide
a safety net for animals that are critically endangered in the wild (Che-Castaldo et
al., 2019; Clark et al., 2023; Mahanayak, 2024; Mastromonaco et al., 2025), yet
their viability depends on the ability to sustain long-lived, healthy populations
(Breithoff &
Harrison, 2020; Naruka & Reddy, 2023; Roslia et al., 2023; Mahanayak, 2024). Longevity influences several key aspects of ex-situ
conservation, including the ability to maintain reproductive success and contribute
to genetic diversity (de Visser et al.,
2022; Nigri et al., 2022; Shilovsky et al., 2022; Kitchener, 2023). As understanding of animal husbandry has evolved
over the last years in the context of keeping wild animals in zoos, longevity has
also increased (de Visser et al.,
2022; Shilovsky et al., 2022; Chaiyarat et al., 2023; Kitchener, 2023). However, a longer lifespan has brought additional
concerns, including the escalation of age-linked diseases(Krebs et al., 2018;
Kitchener, 2023). Tidiere et al
(2016) conducted a study that examined four survival metrics (longevity, baseline
mortality, start of senescence, and rate of senescence) between both sexes of free-ranging
and zoo populations of over 50 mammal species. They discovered that mammals in zoo
populations survived longer than their wild counterparts (84% of species). The benefit
was especially noticeable in species with a quicker pace of life (i.e., short life
span, high reproductive rate, and high mortality in the wild), as zoos protect many
relevant variables, such as predation, intraspecific competition, and diseases.
Several of the oldest animals at Al Ain Zoo in the United Arab Emirates have lived
beyond their natural life spans. Notable examples include a 36-year-old chimpanzee,
a 47-year-old lappet-faced vulture, and a 34-year-old mugger crocodile, as reported
by the Emirates News Agency in 2024. Protected from threats such as overhunting
and urban sprawl, these animals have lived far longer than expected in their natural
habitats (Cuadros-Casanova
& Rondinini, 2021; Akani, 2023; Bobdey et al., 2023; Rathoure, 2024), with some species outliving their natural life
expectancy by several decades, according to Emirates News Agency. Carnivores have
higher survival rates in zoos (Table 1), although they are more susceptible to behavioral
disorders. This emphasizes the need to establish husbandry approaches that reduce
these anomalies while maintaining survival advantages for all species.
Lionesses in zoos live
longer, have lower baseline yearly mortality, a later onset of senescence, and a
lower rate of actuarial senescence (Tidiere et al.,
2016).The comparison of survival measures between wild
and captive populations is not intended to constitute a final ethical assessment,
but rather a synthesis of existing research and illustrative case studies (Table
1) (Tidiere et al.,
2016; Kitchener, 2023).
Table 1. Lifespan of selected animals in managed care and
in the wild
|
Common
name |
Scientific
name |
Food
habit |
Lifespan
in managed care (years) |
Lifespan
in the wild (years) |
References |
|
Giant
tortoise |
Chelonoidis nigra |
Herbivore |
255 |
150 |
(Tidiere et al., 2016; Puga Torres et al., 2017; Pryke, 2020; Reese
& Zug, 2023) |
|
Hare |
Lepus europaeus |
Herbivore |
12 |
4 |
(Schai-Braun et al., 2015; Lado, 2016; Kurta, 2017; Jo et al., 2018;
Smith et al., 2018; Bock, 2020; Kresnye et al., 2022) |
|
Giraffe |
Giraffa camelopardalis |
Herbivore |
36 |
20 |
(Bercovitch & Berry, 2017; Scherer et al., 2024; Lynn et al., 2025;
Martin et al., 2025) |
|
Hyena |
Crocuta crocuta |
Carnivore |
24 |
12 |
(Gicquel, 2023; Kleinlugtenbelt et al., 2023; Martens et al., 2025) |
|
Tiger |
Panthera tigris |
Carnivore |
26 |
13 |
(Sorokin et al., 2016; Tidiere et al., 2021; Aylward et al., 2022) |
|
Black
bear |
Ursus americanus |
Frugivore |
30 |
10 |
(Mesa-Cruz et al., 2020; Rivet, 2022) |
|
Rhesus
monkey |
Macaca mulatta |
Herbivore |
40 |
15 |
(Simmons, 2016; Massey, 2024) |
|
Giant
panda |
Ailuropoda melanoleuca |
Herbivore |
25 |
15 |
(Swaisgood et al., 2020; Yuan et al., 2024) |
|
Pigeon |
Columba livia |
Graminivore |
15 |
6 |
(Stock & Haag‐Wackernagel,
2016; Chitty, 2018; Lea et al., 2024; Mohamed et al., 2025) |
|
Gorilla |
Gorilla gorilla |
Herbivore |
50 |
38 |
(Vermeer & Devreese, 2015; Lowenstine et al., 2016; Strong et al.,
2016; Strong et al., 2017; Morrison et al., 2023; Robbins et al., 2023; Smit
& Robbins, 2025) |
|
Gibbon |
Hylobates lar |
Herbivore |
45 |
33 |
(Terleph et al., 2016; Rebelo, 2019; Lappan et al., 2023; Badri et al.,
2025) |
|
Orangutans |
Pongo pygmaeus |
Herbivore |
60 |
40 |
(Lowenstine et al., 2016; Besnard et al., 2025) |
|
Nile
crocodile |
Crocodylus niloticus |
Carnivore |
100 |
45 |
(Manolis & Webb, 2016; Isberg et al., 2019; Myburgh, 2021; Siddiqui
et al., 2021; Audije‐Gil et
al., 2023) |
|
African
lion |
Panthera leo |
Carnivore |
25 |
10-14 |
(Bauer et al., 2015; Packer, 2019; Ayala-Burbano et al., 2020; Green et
al., 2020; Serres-Corral et al., 2021; Rudd et al., 2024) |
Zoos play an
important role in the research of animal longevity through various approaches (Tidiere et al.,
2016; Roller et al., 2021; de Visser et al., 2022; McEwen et al., 2022; Nigri et
al., 2022; Shilovsky et al., 2022; Kitchener, 2023). Zoos and aquariums collectively care for about
15% of all threatened species worldwide, or roughly one in seven. However, it is
also crucial to consider the number of animals held in the zoos (Da Silva et al.,
2019; Brereton & Brereton, 2020; IUCN, 2023; Miranda et al., 2023; Browning
& Veit, 2024). While individual zoos may not maintain large populations
of a specific species, collectively, zoos manage substantial populations of certain
species, including those that are critically endangered. Zoos, as part of a worldwide
network, should endeavor to safeguard the long-term survival of their threatened
species populations (Schwartz et
al., 2021; Garcia-Pelegrin et al., 2022). For example, the success of captive breeding of
the Southern Corroboree frog from 2010 to 2012 has permitted the reintroduction
of 1,060 captive-produced eggs and an increasing captive population (McFadden, 2013). The captive P. corroboree population is
divided between four institutions in Australia, namely Taronga Zoo (TZ), Melbourne Zoo (MZ), Healesville
Sanctuary (HS), and the Amphibian Research Centre (ARC). The captive program was
initiated at the ARC in 1997, extending to MZ in 2001, TZ in 2006, and HS in 2007
(McFadden, 2013). The size of reintroduction in amphibians supports
conservation research and provides insurance against further declines (Silla et al., 2018). Then, in 2025, scientists mapped the genome of
the highly endangered southern corroboree frog, which is declared "functionally
extinct" due to habitat loss and disease (Kosch et al., 2025;
McFadden et al., 2025). This achievement, made possible by zoo breeding
and reintroduction operations, supports the advancement
of genetic therapies to combat disease and aid in species regeneration and longevity.
The Barcelona Zoo has created specialized geriatric care programs for aged elephants
(Wilson, 2025). These programs include tailored diets, regular health check-ups, and emotional
support to ensure the well-being of elderly pachyderms (Chusyd et al., 2021;
Brando et al., 2023).
Zoos continue to improve
the quality and duration of life for several species by conducting devoted research
and implementing novel care procedures (Espinosa Garcia-San
Roman et al., 2023). The combination of veterinary expertise, strategic
environmental design, and collaborative research ensures that zoos continue to lead
in advancing animal welfare and longevity (Brando et al.,
2023; Martelli & Krishnasamy, 2023; Liptovszky, 2024; Norman & Brando,
2024a). Understanding the complex dynamics of animal behavior
in controlled settings through behavioral study in managed care is vital for illuminating
the needs and welfare of certain species, thereby extending their longevity (Ahmed et al.,
2022; de Azevedo et al., 2023).
Research to improve the
reproductive success in zoos is vital for the maintenance of genetically viable
populations (Iglesias Pastrana
et al., 2021; Farquharson et al., 2022; Mastromonaco et al., 2025). Many species in zoos live longer than their counterparts
in the wild due to optimal nutrition, healthcare, and the absence of natural predators
(Rose &
Riley, 2019; Escobar-Ibarra et al., 2020; Zhang et al., 2021; Browning &
Veit, 2024). Longer lifespans provide additional breeding opportunities
and help ameliorate the effects of a declining natural population. Reproductive
success is particularly important for species that are difficult to breed in managed
care or have small initial population sizes (Attié et al., 2022;
Bussolini et al., 2023; Harris et al., 2023; Schmidt et al., 2024; Izquierdo et
al., 2025). A genetically diverse population is essential
to the long-term health and sustainability of zoo-based insurance populations (Wildt et al., 2019;
Foster et al., 2022; Hoffmann, 2022; Willis, 2022; Smyser, 2024; Speak, 2024). The longevity of animals in zoos allows for the
maintenance of a bigger gene pool, guaranteeing that breeding programs may be handled
successfully to reduce inbreeding and boost genetic variation (Farquharson et
al., 2022; Speak et al., 2023; Norman & Brando, 2024a). With advances in genetic analysis, zoos can now
better manage the genetic diversity of their populations, reducing the risks associated
with genetic bottlenecks (Norman et al., 2019;
Al Hikmani et al., 2024; Speak, 2024). Developments in Critically Endangered Species
Assisted Reproductive Technologies (ARTs) are important in improving reproductive
success in animals kept in zoos. For instance, the International Centre for Zoo
Science at Chester Zoo, which opened in November 2024, has a biobank for endangered
species, diagnostic equipment, and one of the largest animal endocrinology labs
in Europe. The long-term research into rhino hormone tracking by Chester Zoo and
other partners aided in the successful relocation of 21 endangered black rhinos
in northern Kenya. This illustrates how large-scale conservation initiatives can
be guided and facilitated through sophisticated hormone monitoring and the knowledge
gathered from ART research (Wildt, 2003; Comizzoli
& Holt, 2019). Conservation breeding and assisted reproductive
technologies (ARTs) are invaluable tools to save wild animal species that are on
the brink of extinction (Comizzoli, 2018;
Bolton et al., 2022; Hildebrandt & Holtze, 2024). Microfluidic devices recently developed for human
or domestic animal reproductive medicine could significantly help to increase knowledge
about fertility and contribute to the success of ART in wildlife (Comizzoli, 2021;
Le Gac et al., 2021; Yata, 2021). In the history of worldwide breeding programs,
the reintroduction of the Arabian oryx was one of the first-ever successful projects
in the United Arab Emirates (El Alqamy et al., 2012; Linhoff,
2018; Lamb, 2024).
Zoos are actively involved
in the optimization of studbooks and managing genetics to preserve diversity (Lott et al., 2020;
Elsner-Gearing et al., 2024; McLennan et al., 2025). For example, the European Endangered Species Programmes (EEP) cooperatively manage breeding for species that
are threatened with extinction in the wild. For instance, London Zoo participates
in comparable programs for Sumatran tigers and pink pigeons. The sand cat and dama
gazelle are being bred and managed at the Al Ain Zoo in the United Arab Emirates
under the Al Ain Zoo's Conservation Priorities Species (CPS) program. These initiatives
maintain a strong and healthy backup population suitable for potential reintroduction
(Ballou et al.,
2010; El Alqamy et al., 2012; McFadden, 2013). Studbook holders carefully regulate individual
pairing and breeding based on genetic variety (Forti, 2019; Ayala-Burbano
et al., 2020; Moreno et al., 2024). Research focuses on optimizing these genetic couplings
to prevent inbreeding and maintain genetic fitness (Barrett et al.,
2022; Brereton, 2024; Elsner-Gearing et al., 2024; Langenhorst, 2025) and improve vigor and longevity (Kitchener,
2023).
The life expectancy of
animals in zoos, particularly marine mammals, is currently 1.65–3.55 times longer
than that of their wild counterparts (Tidiere et al.,
2016; Rebelo, 2019; Austad, 2022; Tidiere et al., 2023). One of the most significant factors influencing
the longevity of zoo animals is the quality of veterinary care they receive (Tidiere et al.,
2016; Campbell-Ward, 2023; Kitchener, 2023). Improvements in veterinary medicine, including
preventative care, diagnostics, and specialized treatments, have greatly contributed
to the health and lifespan of zoo animals (Espinosa Garcia-San
Roman et al., 2023; Kitchener, 2023; Martelli & Krishnasamy, 2023). These improvements have occurred concurrently
with advances in management practices, which are crucial for population welfare
(Tidiere et al.,
2023; Bhattacharjee & Sharma, 2025). Regular health check-ups, disease management,
and the ability to intervene early in cases of illness or injury have contributed
significantly to increased longevity in zoo populations (Bigby, 2004; Brando
et al., 2023). Veterinarians
use diagnostic tools (Farrow, 2008; Prasad
et al., 2021; Das et al., 2024) such as radiography, ultrasound, and blood tests
to monitor animal health and detect abnormalities early, allowing for timely intervention
and dietary adjustments (Suman et al., 2024;
Bhattacharjee & Sharma, 2025).
Zoos often have on-site
laboratories or partnerships with veterinary hospitals to process tests quickly
(Braverman, 2020;
Miller et al., 2022; Chapman & Dobbs, 2023; Bhattacharjee & Sharma, 2025). According to Martelli& Krishnasamy (2023),
improved welfare leads to better well-being and an increase in the duration of life
(Ward et al., 2018;
Binding et al., 2020; Crittenden & Fang, 2021; Martelli & Krishnasamy, 2023;
Liptovszky, 2024) in zoo populations alike (Edwards et al.,
2019; Vogelnest & Talbot, 2019; Pohlner, 2023). According to Talukdar et al. (2025), the recovery
of the Arabian Oryx is a perfect example of how a combination of commitment, successful
breeding, good welfare, and preventive medicine can contribute to the conservation
of a species that was declared extinct in the wild in the early 1970s, and a Reintroduction
Programme was established in 2007 (Frolich et al.,
2005; El Alqamy et al., 2008; El Alqamy et al., 2012).
Environmental enrichment
is a well-documented and significant aspect in improving the well-being and longevity
of zoo animals (Brereton & Rose,
2022; Rose & Lewton, 2025). Veterinary teams frequently work with zookeepers
and behaviorists to prevent stress-related illnesses through enrichment, training,
and improved habitat design (Garcia-Pelegrin
et al., 2022; Brando et al., 2023; Espinosa Garcia-San Roman et al., 2023; Wilson,
2025). Many species in zoos, notably species with complex
cognitive or social structures, benefit from enrichment programs that mimic natural
behaviors and foster mental stimulation (Brookes et al.,
2022; Bachetti et al., 2024; French et al., 2024). This reduces stress, anger, and aberrant behaviors,
which can harm health and longevity (Edwards et al.,
2019; Norman et al., 2021; Doody, 2023; Norman & Brando, 2024b). The development of enrichment tactics customized
to each species' demands has proven to be an effective approach for enhancing animal
comfort and extending longevity in managed care (Kresnye et al.,
2022; French et al., 2024; Richardson, 2024). Welfare evaluations in zoos using the six Cs of
Coping, Comfort, Choice, Control, Challenge, and Compassion (Jones et al., 2022;
Gandia et al., 2024; Rose & Lewton, 2025) can be valuable for learning what species need
in managed care and how it might be better provided to promote animal welfare (Escobar-Ibarra
et al., 2020) and the well-being of their human caregivers as
well (Ballou et al.,
2010; Rose & Riley, 2019; Farquharson et al., 2022; Bacon, 2023; Watters
& Krebs, 2025). Many species' longevity is also dependent on their
social structure. Some animals, such as elephants and monkeys, need complex social
connections to thrive in managed care (Kusumaningsih &
Rosiana, 2023; Pohlner, 2023; Doyle et al., 2024; Kelly et al., 2025). Properly managed group dynamics can reduce stress,
encourage healthy behavior, and ensure longer life expectancy. In rare circumstances,
socialization with conspecifics or other species has been found to improve survival
and reproduction rates (María C
Fàbregas et al., 2020; Kilgour et al., 2024; LaDue et al., 2024).
Despite the many advances
in zoo management, challenges remain in maintaining longevity in the ex-situ populations
(Hosey et al., 2020).The difficulty of duplicating natural habitats, as well as the stressors
of managed care, can nevertheless have an impact on animal health and lifespan (Clay & Visseren-Hamakers,
2022; Tuite et al., 2022; Bandeli et al., 2023; Doyle et al., 2024). The success of ex-situ populations depends heavily
on effective collaboration between zoos worldwide to ensure genetic diversity (Shaw et al., 2024), appropriate breeding programs (Wildt et al., 2019;
Che‐Castaldo et al., 2021; Hutu &
Oldenbroek, 2025), and the availability of genetic material for reintroduction
efforts (Iglesias Pastrana
et al., 2021; Foster et al., 2022; Shaw et al., 2024).
Factors like chronic
stress, obesity (Warwick, 2023), limited movement, hard flooring, and frequent transfers between facilities
significantly contribute to the reproductive failure and death of animals in zoos
(Vermeer &
Devreese, 2015; Rees, 2020; Chusyd et al., 2021; Doyle et al., 2024; Wilson,
2025). Health problems such as foot disease, arthritis,
tuberculosis, and infertility are common and often lead to early euthanasia (Holdgate et al.,
2016; Doyle et al., 2024). Many animals in some zoos, especially elephants,
suffer from complex foot and joint disorders caused by standing on concrete and
having little space to walk (de Sales et al.,
2020; Rees, 2020; Kumar et al., 2024). Living in managed care can also harm psychological
health. It disrupts social structures and lacks environmental variety. Young elephants
separated from their mothers often experience high infant mortality and lower adult
survival, likely starting after birth or early in life. Although zoos face scrutiny,
recent efforts in several accredited facilities, including programs for older animals,
natural habitats, and enrichment activities, show promise in improving health for
aging animals. However, a broad comparative study reveals that while shorter-lived
species may benefit somewhat from managed care, long-lived species still face a
reduced lifespan and faster aging compared to their wild counterparts. However,
continuous improvement of zoo management techniques and animal welfare (Bansiddhi et
al., 2020; Binding et al., 2020; María C. Fàbregas et al., 2020; Doody, 2023;
French et al., 2024; Liptovszky, 2024), studies will ensure that zoo populations are not
only sustainable but also contribute to the long-term survival of endangered species
(Binding et al.,
2020; Lemasson et al., 2020; Liptovszky, 2024; Salas et al., 2024).
Longevity in zoo animals is a crucial component of efficient ex-situ conservation, as it directly contributes to the viability and sustainability of insurance populations for endangered species. Zoos play a crucial role in preventing biodiversity loss by extending reproductive potential, preserving genetic diversity, and supporting ongoing research and veterinary advancements. Modern zoos have evolved into centers of scientific excellence, where improved animal husbandry, specialized geriatric care, and enrichment initiatives work in tandem to prolong lifespans and enhance animal well-being. While challenges remain in replicating natural environments and managing genetic and behavioral complexities, continued innovation and international collaboration are vital to overcoming these limitations. Ultimately, the promotion of longevity in captive populations enhances the global capacity to safeguard species on the brink of extinction, reaffirming zoos' crucial role in the broader conservation landscape.
Acknowledgements
The authors are grateful to the management of Al Ain Zoo. We want to extend our gratitude to the Conservation team at Al Ain Zoo. The authors have reviewed and edited the output and take full responsibility for the content of this publication.
Funding
No funding available for this study.
Authors’ Contribution
Admire Chanyandura: Conceptualization, Methodology, Writing Original draft preparation. Amna Mana Alotaiba: Writing, Review, Editing, and Validation. Hessa Ahmed Alqahtani: Writing, review, and Investigation. Mouza Mubarak Alhajeri: Investigation, Visualization. All authors have read and agreed to the published version of the manuscript.
Ethical approval
Not applicable.
Informed consent
Not available.
Conflicts of interest
There is no conflict of interest to declare.
Data availability statement
The authors declare that data can be provided by the corresponding author upon reasonable request.
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