Clawing at the Cages: The problem with keeping big cats in zoos

CLAWING AT THE CAGES

THE PROBLEM WITH KEEPING BIG CATS IN ZOOS

Published: September 2024

Jaguars

onca)

Leopards (Panthera pardus)

Lions

leo)

Pumas (Puma concolor)

Snow

Tigers

(Panthera uncia)

tigris)

FOREWORD: CLAWING AT THE CAGES  LIFE WITHOUT HOPE

Perhaps more than any other species, big cats represent all that is wild and free. Life in the wild is tough for an apex predator. The survival challenges are manybut what a life! And how pale and diminished, by comparison, is life in a zoo.

Yes, the food comes on time; there is veterinary care (sometimes); you might be protected from the worst of the weather…

But a life without choice is a life without hope.

You can’t choose where you sleep – it is chosen for you. The scrap of land you call home – that is chosen too. What you eat, when you eat, who you eat with, with whom you mate. Whether you have cubs and what happens to those cubs. It is all planned, predetermined. Your life of exploitation is not your own.

This new report, Clawing at the Cages, lays bare the reality of what individual big cats endure in so many zoos. It exposes the dubious conservation claims that are used to justify the captive keeping of thousands of big cats for whom the chance of a wild and free life is a fantasy. They’ll try to tell you it’s all about conservation, but the reality is these big cats will never go back to the wild. They will be on display 365 days a year for our entertainment and so-called education.

Big cats in the wild are faced not only with the natural challenges that their kind has evolved to overcome - the search for food; the risks of the hunt; the protection of family; the defence of their huge territories - but, in addition, they are confronted by the human-imposed challenges that make their survival even more precarious. The loss of wild prey; conflict with human communities; revenge killings for livestock predation; the fragmentation of habitat; trophy hunting; body part trade.

So, faced with the evidence, we have to decide: do we get serious about finding ways for big cats and humanity to tolerate each other and co-exist in the harsh and remote landscapes they share? Or do we lamely accept the zoo narrative and ignore the suffering of those for whom life is defined by a captive life-support system that gives them the basics – food, water, shelter, and security – but deprives them of that most essential prerequisite for a life worth living - freedom.

Will Travers OBE Executive President & Co-Founder Born Free Foundation

EXECUTIVE SUMMARY

Beloved and revered the world over, big cats are commonly displayed in zoos and other wild animal exhibits because of our desire to see them in the flesh, despite the toll this takes on the animals themselves.

This report seeks to explore the significant concerns surrounding the trade in and keeping of big cats by zoos.

The report finds that:

l Inadequate environment: Zoos fail to provide adequate environments for big cats, including lack of space, lack of opportunities to perform natural behaviours, and the lack of ability to hide from public view. Big cats are also regularly confined in tiny night quarters during the hours when zoos are closed, but when most would naturally be most active.

l Social deprivation: Zoos also fail to meet the social and behavioural needs of big cats. Naturally solitary big cats, such as tigers, are often forced to live with other individuals and social big cats, such as lions, are prevented from creating natural groups. Big cats in zoos are unable to perform fundamental natural behaviours such as hunting, while often being housed close to prey animals who also suffer stress from being forced to live near predators.

l Inbreeding: Inbreeding of big cats in zoos has become commonplace due to limited genetic diversity among captive populations, as well as unethical and deliberate inbreeding of colour morphs such as white tigers and lions, resulting in additional significant health issues for the cats involved.

l Lack of conservation purpose: Due to the inbreeding of big cats in zoos, as well as their habituation to humans and their lack of development of natural behaviours, big cats kept in zoos are generally not candidates for release to the wild. As such, extensive and ongoing breeding programmes typically contribute little or nothing to conservation and largely serve to ensure that zoos remain ‘stocked’ with these animals.

l Zoothanasia: Zoos around the world have killed healthy big cats due to overstocking and overcrowding, and the lack of perceived contribution to breeding programmes. Other healthy big cats have been killed when human error or enclosure failure allowed their escape, or when attacked by conspecifics in their enclosures because of forced introductions.

l Compromised health: The overall health and welfare of big cats is compromised in zoos. This results in high mortality (particularly in infants), and recognisable signs of stress in the form of stereotypic behaviours.

The problems with keeping big cats in zoos are significant and the complex needs of these animals can never be fully met in zoo settings. Generations of big cats have been displayed in zoos, but they have never truly adapted to captivity and continue to display signs of suffering through repeated behavioural indicators. It is time for us to accept the evidence provided by extensive and growing data on the myriad ways that big cats fail to thrive in zoos, and take concrete steps to bring an end to their captivity.

As a consequence of their lifetime in captivity, the vast majority of these cats cannot be released into the wild. However, genuine sanctuaries do exist, which in some cases provide semi-wild conditions for big cats to live out the remainder of their lives free from exploitation. The objectives and ethos of such facilities sets them apart from zoos. In the 40 years sinceit was founded as ‘Zoo Check’ in 1984, Born Free has rescued 117 big cats from zoos, circuses and the illegal pet trade and relocated them to various rescue and sanctuary environments. Genuine rescue centres and sanctuaries provide lifetime care for their animals, do not participate in captive breeding and do not exploit their animals for commercial purposes.

Keeping big cats in zoos clearly serves no clear conservation purpose. For these awe-inspiring animals to be reduced to living exhibits for public entertainment is unconscionable.

We call upon policy makers and the zoo industry to take immediate steps to phase out the keeping of big cats in zoos, beginning with an end to their breeding in captivity.

Instead, the focus must shift to implementing effective measures to protect wild big cats in their natural habitats as part of functioning ecosystems.

Only then can future generations of big cats be truly safeguarded.

© Britta Jaschinski, Born Free

THE LANDSCAPE OF BIG CAT POPULATIONS IN EUROPEAN ZOOS

There are estimated to be over 3,000 big cats currently kept in accredited and non-accredited zoos throughout Europe. ‘Big cats’ include all living pantherines (Panthera spp.) – jaguars (Panthera onca), leopards (Panthera pardus), lions (Panthera leo), snow leopards (Panthera uncia) and tigers (Panthera tigris) –as well as cheetahs (Acinonyx jubatus) and pumas (Puma concolor). There are also a number of regional sub-species recognised within big cat species, particularly for cheetahs, leopards, lions and tigers.

As of August 2024, every species of big cat is represented in UK and wider European zoos. Regional Collection Plans, which often contain species population data for zoos which are members of the European Association of Zoos and Aquaria (EAZA), are, mystifyingly, not publicly accessible. Therefore, the statistics provided within this report are based on the most up-to-date information available, which have been collated and cross-referenced from various sources including scientific literature, zoo industry media releases, stocklist data acquired via Freedom of Information laws (UK only), and online zoo databases.

Species Table 1: Summary of big cat species conservation status.

Conservation Status according to the IUCN Red List of Threatened Species

Vulnerable

Near threatened

Vulnerable

Vulnerable

Least concern

Vulnerable

Endangered

regional

Identification of ex-situ captive breeding as a recommended conservation action

Ex-situ breeding mentioned as a conservation action, but not considered in detailed assessment.

No

Ex-situ breeding mentioned as a conservation action, but not considered in detailed assessment.

EAZA Ex-situ Programme (EEP) Established

Northern cheetah. Southern cheetah.

Ex-situ breeding listed as a conservation action but not considered in detailed assessment.

No No No

Yes

Sri Lankan leopard. Amur leopard.

Persian leopard. North Chinese leopard.

African lion.

Asiatic lion.

No

Yes

Amur tiger. Sumatran tiger.

CHEETAHS

(ACINONYX JUBATUS)

Cheetahs are widely known as the fastest living land mammal, reaching speeds up to 103 km per hour (Sharp, 1997). Although commonly classified as a big cat, cheetahs and pumas (see page 11) cannot roar like members of the Panthera genus. Jaguars, leopards, lions and tigers all possess a length of cartilage, connected to their hyoid bone, running up to their skull which enables this ability. Conversely cheetahs produce a chirping sound but can also purr like other smaller wild cat species. However, cheetahs are also distinct from other smaller wild cats due to their inability to fully retract their claws. Extant populations are currently found in the north, east and south of Africa as well as the Middle East (Durant et al. 2023). The International Union for Conservation of Nature (IUCN) Red List of Threatened Species currently recognises four subspecies (A. j. hecki, A. j. jubatus, A. j. soemmeringii, A. j. venaticus) although further genetic analysis is still required to confirm their accuracy. EAZA breeding programmes have been established for two of these subspecies (Table 1).

Cheetahs occupy a variety of habitats including dry forest, thick scrub, grassland and desert and are primarily active during the day (Caro, 1994). Cheetahs live in social groupings which are unique among felids, with females being solitary and males either being solitary or forming coalitions, often consisting of their brothers. They hunt a wide range of prey including small to mid-size ungulate species, small mammals, grounddwelling birds and, occasionally, larger ungulates (Durant et al. 2023).

According to the International Cheetah Studbook, the captive global cheetah population in 2019 was

1,820 animals at 281 known facilities in 46 countries. The largest number of captive cheetahs were located in North America (27.6%), followed by Southern Africa (25.6%), and Europe (22.1%). In total, 480 cheetahs were registered at 121 facilities in Europe in 2019. Of the 1,820 captive cheetahs worldwide, 88% (1,604 individuals) were reported to have been captive-born and 7% (128 individuals) were wild-caught. The origin of 88 animals (4.8%) is unknown. Of the 281 known facilities that held cheetahs in 2019, 10%, (30 facilities) saw cheetah births. However, 25.3% of cubs born in 2019 died in infancy.

Historically, since 1967 around 25% of all cheetahs that are recorded within the studbook were wild caught. Of the 7,257 individuals for which a cause of death was listed, 44% (3,215 individuals) died from unknown causes; 20% (1,476 individuals) from infection; 12% (895 individuals) by euthanasia;* 4% (298 individuals) were stillborn; 3% (244 individuals) from injuries from exhibit mates; 3% (248 individuals) from environmental/behavioural conditions; 1% (130 individuals) of old age; and <1% (42 individuals) from anaesthesia/restraint. The deaths of 28% of the entire historic population were unspecified.

*NB: There is no distinction made in studbooks between true euthanasia (defined by the Royal College of Veterinary Surgeons (2024) as “painless killing to relieve suffering”) and killing healthy animals for zoo management purposes. For more on the way in which the term “euthanasia” is manipulated by the zoo industry, see page 28.

JAGUARS (PANTHERA ONCA)

Jaguars are found throughout most of Central and South America, most commonly in habitats characterised by dense tropical forest and the presence of water bodies (Quigley et al. 2017). They are more strongly associated with being present near bodies of water than any other big cat. They may also be found in swamp forests, grassland and woodland, often in close proximity to a water course. The current status of subspecies remains unclear, however regional differences have been identified (Quigley et al 2017).

Jaguars are reported to prey on as many as 85 species including mammals, birds and reptiles,

resulting in a highly variable diet (Seymour, 1989). However, it is estimated that 50% of jaguar kills involve larger prey, such as large-bodied ungulates (Scognamillo et al. 2002). Jaguars are solitary, with individuals only coming together to reproduce, or while a female is rearing her offspring (Sunquist & Sunquist, 2002). On average, a female will give birth to two offspring who are typically dependent on their mother for 15-18 months and may remain within her territory for up to 24-30 months for females and 36-48 months for males.

There are estimated to be at least 120 jaguars in over 90 European zoos.

LEOPARDS (PANTHERA PARDUS)

Leopards occur in a wide range of habitats, including desert, semi-desert, arid, mountainous and rainforest environments across Africa and Asia (Stein et al. 2023). They are believed to exist from as far west as Guinea Bissau in north-west Africa, to the Russian Far East. In mountainous environments, they live up to an altitude of 4,600m on Mount Kenya and 5,200m in the Himalayas. Leopard subpopulations are also found in suburban and urban areas in India and parts of sub-Saharan Africa.

Leopards hunt a wide variety of prey, with a preference for hunting in areas where there is

sufficient cover. This enables individuals to cache captured prey within dense vegetation or hoist it up into trees away from competitors (Hayward et al. 2006).

The IUCN Red List of Threatened Species currently recognises eight leopard subspecies (P. p. delacouri, P. p. fusca, P. p. kotiya, P. p. melas, P. p. nimr, P. p. pardus, P. p. orientalis, P. p. tulliana).

There are estimated to be more than 340 leopards in over 240 zoos in Europe; this includes six different reported subspecies.

LIONS (PANTHERA LEO)

Lions are capable of surviving in a broad range of habitats including desert, forest, grassland, savanna and shrubland (Nicholson et al. 2023). Despite their nickname of ‘King of the Jungle,’ tropical rainforests are one of the few habitats they are absent from. The global population of lions is highly fragmented, and of all carnivores, the range of lions has undergone the greatest contraction (Nicholson et al. 2023). Their numbers are greatest in southern and eastern Africa, although small populations are still found in Central and West Africa, as well as India.

Unlike most other big cats, lions live in social groupings, with related females forming prides and males (related and unrelated) forming competitive coalitions. Average pride size varies depending on region, with prides of up to 30 individuals observed in larger ecosystems (Nicholson et al. 2023). Pride size in Asiatic lions (a subclade of the Northern lion) is typically observed to be smaller than that of African lions. Lions will predate almost any animal and will also scavenge and take the kills of other predators, including cheetah (Hayward & Kerley 2005).

Despite being highly social animals, at the time of writing five UK zoos were keeping solitary lions.

The IUCN Red List of Threatened Species currently recognises two lion subspecies (P. l. leo and P. l. melanochaita). Panthera leo leo, referred to as the Northern lion, encapsulates what are commonly referred to as Asiatic lions, along with those found in Central and West Africa, and are genetically distinct from Panthera leo melanochaita found in Eastern and Southern Africa.

There are at least 1,000 lions in European zoos according to European breeding programme data, making them the most common big cat in European zoos. However, figures may be significant underestimates due to the number of European zoos with lions that are not part of the European breeding programme.

At the time of writing, there were approximately 172 lion adults and cubs (17 Asiatic lions and 155 African lions, including 12 ‘white lions’) in 34 zoos across the UK according to recent zoo stocklists and websites.

PUMAS (PUMA CONCOLOR)

Pumas, also known as cougars or mountain lions, are found in a wide range of habitats across North, Central and South America, inhabiting all forest types as well as lowland and montane deserts. While habitats with dense understory vegetation are preferred, they can also live in very open habitats with little vegetative cover. Pumas can hunt and consume large prey, but when available, small to medium-sized prey form the majority of their diet (Nielsen et al. 2015).

Pumas have the longest hind legs in relation to body size of all the big cats. Being built for sprinting, they can quickly reach speeds of over 30mph. They are also incredible jumpers, able to jump to heights of over 5m into a tree, or over 10m across level ground (Bryce et al. 2017).

There are estimated to be at least 120 pumas in over 50 European zoos.

SNOW LEOPARDS

(PANTHERA UNCIA)

Snow leopards inhabit mountainous rangelands in the Himalaya and Tibetan Plateau, usually at elevations of 3,000m to over 5,000m (McCarthy et al. 2017). Their thick grey-white fur with dark spots keeps them insulated as well as camouflaged in high-altitude mountainous terrain. While they may sometimes be found in relatively flat or rolling areas in parts of Mongolia and the Tibetan Plateau, they favour steep and rocky terrain, with mountain ridges and cliff edges being common travel routes. Despite their name, they are more closely related to tigers than they are to leopards (O’Brien & Johnson, 2007).

As of 2024, 187 individual snow leopards were reported to be held in over 80 zoos that participate in the European Ex-situ Programme, however more may be present at unaccredited facilities. It is claimed that “The captive snow leopards help their counterparts in the wild by providing precise life history information and safe anaesthesia protocols as well as functioning as ambassadors for funding in situ conservation and field studies” (Nygren et al. 2024).

TIGERS (PANTHERA TIGRIS)

Tigers are the largest big cat in terms of weight, with the Amur tiger being the largest of all. Subpopulations inhabit temperate, tropical, and subtropical forests within south and southeast Asia as well as temperate forests in China and Russia. Tigers are generally solitary with the territories of males overlapping with those of several females.

A tiger’s diet is usually made up of ungulates, however they will also predate on sup-optimal prey or animals much larger than themselves if their preferred prey is lower in abundance.

Six extant subspecies are recognised by the IUCN Red List of Threatened Species (P. t. altaica, P. t. corbetti, P. t. jacksoni, P. t. sumatrae, P. t. tigris, P. t. amoyensis).

In February 2024, there were at least 640 individual tigers in over 400 European zoos, including representatives of five of the six recognised subspecies (all but P. t. amoyensis).

CAPTIVE WELFARE ISSUES

Although only a small proportion of zoos located within Europe are accredited by EAZA, those facilities are required to meet EAZA’s Standards for the Accommodation and Care of Animals in Zoos and Aquaria. The standards outline housing and enclosure requirements designed to make the lives of captive animals “as fulfilling as possible”. Section 1.2 (1) of the standards states that zoos must provide “a physical space that is appropriate to the species, taking account of their three- dimensional needs”. Additionally, section 1.5 (1) states, “Animals kept in EAZA collections should be encouraged to perform as much of their natural behavioural repertoire as possible and acceptable. Whenever possible unnatural behaviour should be prevented or actively discouraged” (EAZA, 2019). The very act of keeping big cats in a zoo environment, which typically provides an extremely small enclosure size compared to natural range sizes, and the near-constant presence of humans and other animals at the facility, directly conflicts with these mandatory obligations.

For every EAZA accredited zoo within Europe, there are likely to be many more unaccredited facilities, many of which also keep big cats. Most published research on big cats in zoos is believed to be conducted at accredited facilities. Therefore, the findings are likely to present a skewed perspective on the conditions that big cats experience in zoos across Europe. Since many unaccredited facilities are located in countries which have little or no specific zoo licensing legislation, it is likely that the typical conditions in which big cats are kept across European zoos is considerably worse than that reported in the published scientific literature.

INADEQUATE ENCLOSURES

Enclosure size

A recent study collected enclosure size data across 44 European zoos (Kleinlugtenbelt et al. 2023) (Table 2).

Table 2: Comparison of average-sized big cat enclosures to standard sport pitches and facilities. Average enclosure size data taken from Kleinlugtenbelt et al. (2023).

Species

Lion

Cheetah

Tiger

Snow

Leopard

Jaguar

Average Enclosure Size (Range) (m2) 5,321 (150 – 40,000)

(200 – 6,700)

(15 – 10,000)

(40 – 5,400)

671 (40 – 3,400)

510 (135 – 900)

Comparative Size (m2)

< Pitch at Wembley Stadium (7,140)

½ an NFL American football field (2,230)

NHL ice hockey rink (1,586)

< Olympic-sized swimming pool (1,250)

< Two netball courts (930)

< Two tennis courts (521)

In the wild, tigers have large territories ranging from 7-1,000km2 (Breton & Barrot, 2014). Therefore, even the largest tiger enclosure at 10,000m2 (0.01km2) is still 700 times smaller than the reported minimum tiger range of 7km2. In India, it was recently documented that a wild tiger dispersed over 2,000km in 18 months and continued to travel 25-30km per day in search of a mate (Pinjarkar, 2023). Increased pacing in big cats (see Stereotypical Behaviour below) has been associated with smaller enclosure sizes (Quirke et al. 2012; Breton & Barrot, 2014).

Jaguars and cheetahs are currently the only big cat species that are the subject of publicly available EAZA Best Practice Guidelines. For jaguars, the EAZA guidelines recommend that their outdoor area and inside enclosure should each be over 200m2 plus an extra 50% for every additional animal. This suggests a minimum total area for a jaguar of 400m2, which is smaller than a basketball court. The North American Association of Zoos and Aquariums (AZA) acknowledges that trauma among big cats from an enclosure companion is a common outcome of small enclosure sizes and recommends housing jaguars alone or in same-gender or sibling pairings to reduce the risk of potentially fatal fights. The jaguar EAZA Best Practice Guidelines state, “the recommended social structure for managed jaguars is an adult pair (consisting of a male and a female), or a mother with immature offspring. Housing a single animal is also perfectly

Figure 1: The number of times each big cat species would need to walk around the perimeter of their average-sized enclosure every day to achieve their daily travel distance in the wild.

acceptable” (EAZA, 2022). They also acknowledge that “most large felids are solitary in nature except during periods of breeding activity, therefore extreme caution and patience is recommended during introductions”. To recommend housing adult male and female pairs together appears to prioritise breeding, which continues to add more animals into already small spaces, over the potential welfare risks associated with small multi-animal exhibits.

The cheetah EAZA Best Practice Guidelines provide less specific guidance in relation to enclosure sizes, stating that individual pens should be no less than 6m2 and the smallest outside enclosure should not be less than 20m2 (EAZA, 2018). Crucially, no minimum dimensions are provided for a cheetah’s main outside enclosure. The guidelines state that “it is impossible to recommend a minimum size for the main enclosure” because “it depends on the topography, furnishings, group composition, target of exhibit and many other factors”. Given their large natural home range size, it is unclear why EAZA does not recommend a minimum enclosure size for cheetahs as it does for other species.

PUBLIC REPORT 2024



UK:

“The zoo looked okay from the outside. But two snow leopards were kept in an environment too small for them, with their only shelter being a man-made cave with little room behind for both the animals.”

For UK zoos, where it was possible to estimate enclosure sizes from satellite imagery or from measurements published online, the median enclosure size for lions and tigers is estimated to be less than 2,800m2 (0.7 acres) and less than 2,400m2 (0.6 acres) for cheetahs. While some safari parks have significantly larger enclosures than the median, they still restrict animals to spaces many orders of magnitude smaller than those in which these big cats have evolved to roam.

In the five years up to June 2024, 59% of all public reports received by Born Free through our Raise the Red Flag programme in relation to big cats in zoos referenced concerns about the size of the animal’s enclosure. The concerns received related to 72 individual European zoos, including 36 in the UK.

CHEETAH

JAGUAR

LEOPARD

LION

SNOW LEOPARD

TIGER

CASE

STUDY: LINCOLNSHIRE WILDLIFE PARK

In 2021, the formal inspection report for Lincolnshire Wildlife Park in the UK highlighted a worrying situation with the tiger enclosure. While inspectors complimented the enclosure design, timesharing issues among these solitary animals meant that the zoo’s nine tigers, puma and leopard had limited access to just five outdoor enclosures. Tigers were mostly kept in small pens (24m2 indoor pens or 96m2 outdoor holding pens) with minimal enrichment and without free access between their indoor pen and outdoor holding pen. Restricting outdoor access goes against zoo guidelines, such as BIAZA’s recommendation for 24-hour access to outdoor areas. Zoo inspectors also found this to be in breach of Section 9 of the Animal Welfare Act 2006, which requires those responsible to ensure animal welfare needs are met for animals under their care. The main outdoor enclosure measures 4,400m2. Over a one-month period one tiger only

had access to it on 11 days, and for an average of 1.8 hours per day.

When the enclosure was built in 2017 it was originally home to 11 tigers. While the high number of tigers resulted from their rehoming from private facilities by the local authority, rather than as a result of a breeding programme, this still serves as a worrying example of how big cats in zoos can be confined to small living quarters for prolonged periods of time. More recently, the number of tigers at the zoo has reduced, which may have improved the timesharing situation since the 2021 inspection report.

Additionally, at the time of writing, the zoo’s lion enclosure, home to two white lions, is one of the smallest lion enclosures in a UK zoo, being less than 0.0004% of a lion’s median home range size.

Photos

© Aaron Gekoski, Born Free

Confinement to night houses

Many zoos confine their big cats to the smaller and less complex indoor enclosures (sometimes referred to as ‘night houses’ or ‘offexhibit’) for ‘safety reasons’, once visiting hours end (Big Cat Rescue, 2024), meaning that their movement and behaviour are even more severely restricted at the time of day they would typically be most active in the wild.

This captive management directly conflicts with normal big cat behaviour. For example, studies of wild jaguars reveal peaks in their activity before dawn and at dusk (0330-0600 hours and 1830-2100 hours) (Schaller & Crawshaw, 1980). Yet most zoos are open to visitors through the day when the cats would naturally be resting. Leopard activity also peaks outside of typical zoo operational hours, at dawn (around 0600-0659 hours) and dusk (around 1700-1759 hours) (Azmi et al. 2017). Among big cats, only cheetahs are considered to be primarily active during the day.

Proximity to other species

By design, and largely for what are intended to be ‘educational’ purposes, zoos often group animal exhibits based on shared geography, similar climatic preferences, and/or comparable distribution of animals (WAZA, 2016). For example, many zoos have areas identified as ‘African Savannah,’ ‘Asian Rainforest,’ or ‘South American Jungle’ but these are little more than design themes which bear no meaningful resemblance to the areas they claim to replicate. Additionally, designing a zoo in this way negatively impacts animal welfare, as the nature of these broadly themed exhibits requires predominantly solitary, predatory, and prey species to coexist in unnatural ways that conflict with their many evolved behaviours enabling them to thrive in these roles in the wild. In the UK, of the zoos currently housing big cats, the majority house at least one of their big cat species in close proximity to prey (either natural prey for the big cats or a species considered as a ‘prey species’) according to their most recent site map and satellite imagery (Google Earth, 2023).

PUBLIC REPORT 2024  BULGARIA:

“Upon arrival I noticed the zoo itself looked very run down and almost abandoned. As I walked round the different enclosures and saw the different animals I saw large animals such as tigers, lions, jaguars etc, in small enclosures with little to no grass, water or proper facilities. All enclosures were entirely concrete. Any patches of grass that used to be there were now dead. All indoor enclosures had a horrible smell as if they were never cleaned. They all smelt of rotting meat, fish and faeces.”

Big cats have evolved to use scent marking and vocalisations to establish their territory and warn other big cats. Prey animals have simultaneously evolved to detect these chemical warnings to avoid such spaces. Research confirms that the presence of predators can induce extreme stress and powerful physiological responses in prey, including inhibition of activity; suppression of non-defensive behaviours like foraging, feeding, and grooming; and movements to locations where such odours are not present. However this ability is artificially limited by the confines of a zoo enclosure. This may result in chronic stress in prey species (Learmonth, 2019). In contrast, big cats kept in semi-wild sanctuaries may be able to sense prey species beyond the sanctuary boundary, but these species are able to move away should they choose to.

Figure 2: Current enclosure layout of Whipsnade Zoo, UK, showing that lions are housed next to and potentially in view of prey species (zebras and ostrich). © Google Earth, 2023

CASE STUDY: PREDATOR  PREY PROXIMITY

There is an assumption in the zoo industry that predator and prey species (or multiple territorial predator species) will habituate to each other over time in a captive setting (Stanley & Aspey, 1984). In a study that tested prey species’ awareness of a predator in a zoo by studying an exhibit with five species of African ungulates separated by a dry moat from their natural predator, the African lion, the researchers measured the ungulates’ activity budgets in response to various lion behaviours. The results indicated that ungulates spent significantly less time engaging in seven behaviours (including lying down, feeding, drinking, sniffing the ground, sniffing each other, defecating, and urinating) when the predator was visually present than when visually absent. The authors concluded that the changes in ungulate behaviour indicated an awareness of the predator; for example, the prey spent less time with their heads down (engaging in feeding, drinking, and sniffing the ground behaviours) when the predator was visible, allowing more time for predator surveillance. These results indicate that the ungulates in this zoo exhibit modified their behaviour when a lion was visually present, potentially also indicating increased stress levels because of more time spent in a vigilant state (Stanley & Aspey, 1984).

This deleterious predator/prey dynamic that negatively impacts animal welfare in captivity holds true even for animals that do not share a

recent evolutionary history or captive-raised animals that may never have learned predatoravoidance behaviours from parents or conspecifics. For example, one field study (Hettena et al. 2014) investigated the ability of mule deer to discriminate among familiar predators including coyotes and pumas versus an evolutionary relevant yet unfamiliar predator to which mule deer had no recent exposure: locally extinct wolves. They discovered that the mule deer not only responded to each of the predator sounds but discriminated between each predator species, including the wolves that had been extinct from the study area since the early 1900s. As highlighted by these results, the fear and avoidance behaviours demonstrated by prey species are genetically ingrained in these animals, and likely do not diminish in intensity or disappear completely as a result of adaptation to unnatural zoo settings.

While the zoo industry may advocate for such enclosure configurations, stating that “mild harms” are natural and can result in beneficial physiological responses for both predator and prey, researchers often highlight the difference between acute versus chronic stressors. Static enclosures result in prolonged and perhaps constant exposure which can result in frustrationtype behaviours in predators and sustained stress for prey species (Learmonth, 2019).

© Jo-Anne McArthur, Born Free

Further, predator odours can have profound effects on the endocrine system of prey animals by suppressing testosterone and increasing levels of stress hormones including corticosterone and adrenocorticotropic hormone (ACTH) (Apfelbach et al. 2005).

Tigers have scent glands on their tails, paws, and face, and often leave olfactory signals for other tigers using various methods including urine spraying, scraping surfaces with deposits of urine, faeces, or anal gland secretions, clawing, cheek rubbing, and vegetation flattening. In addition to these chemical tactics, tigers also often engage in night-time patrols of their territory. During these patrols, they may renew scent marks and vocalise to reinforce their ‘ownership’ of the area. In the wild, territorial patrols help deter other tigers from entering established territories, while simultaneously alerting prey to their presence and proximity (Smith et al. 1989). One can imagine the elevated frustration level tigers and other big cats in captivity must experience when constantly detecting the ‘territorial’ markings of other big cats in a zoo (without the option to properly defend it), making them constantly aware of their presence.

STEREOTYPICAL BEHAVIOUR

Stereotypical behaviours, also known as ‘zoochoses’, are repetitive, unvarying and seemingly functionless behaviours that result from the lack of behavioural opportunities in a captive environment. Stereotypical behaviours in big cats are often characterised by pacing, route tracing, excessive grooming, head-twisting, tail and toe sucking and fur plucking (Wooster, 1997).

At the National Zoological Park in New Delhi, India, a study revealed a positive correlation between visitor density and noise, and stereotypical behaviours in Bengal tigers. During periods of high noise and density of visitors, tigers experienced higher rates of stress and engaged in altered behavioural patterns, including an increase in the display of stereotypical behaviours (Vashisth et al. 2023). Similarly, a study at Parco Natura Viva in Italy found that Amur tigers and snow leopards performed fewer species-specific behaviours and exhibited significantly longer periods of inactivity when visitors were present (Spiezio et al. 2023). Visitor presence was also linked to behavioural changes associated with chronic stress in Eurasian lynx (Lynx lynx), bobcats (Lynx rufus) and Asiatic lions (Suárez et al. 2017). Significant malformations of the skull in captive tigers were attributed to excessive grooming behaviour and a reduction in the jaw muscles due to eating processed food (Duckler, 1998).

Providing opportunities to perform natural species-specific behaviours can improve the health and wellbeing of animals in captivity, however they often do not eliminate stereotypical behaviours in big cats (Quirke & O’Riordan, 2011; Spiezio et al. 2023; Seyrling et al. 2024). Some zoos attempt to justify keeping tigers and other big cats known to be stressed by visitor presence by providing enclosure elements that function as auditory and visual barriers (e.g., vegetation, rocks,

from Bandeli et al. (2023) and Kleinlugtenbelt et al. (2023).

PUBLIC REPORT 2024  UK:

“I'm concerned for the welfare for the leopard at *** zoo. Under stimulated, stressed and bored animals in enclosures that are far too small for them is a major concern and should be a priority for the authorities. This leopard was doing nothing but pacing back and forth in the same spot for a considerable long period of time. It wasn't feeding time and there was nothing else to be used as an excuse to be stressing him or her. The enclosure is far too small.”

Species

Table 3: Recreated

and multilevel terrain) (AZA Tiger SSP, 2016). These elements may dampen the intensity of constant stressors but will never completely eliminate them, and the very fact they are deemed necessary represents a clear recognition that visitor presence and proximity negatively affect the welfare of the animals. Zoos are financially incentivised to ensure their visitors can see the animals they keep, often to the detriment of many big cats who are naturally shy and elusive.

In an effort to quantify the occurrence of stereotypical behaviours in captive species, a review estimated that 20 species of captive Felidae spent between 10.5–48.0% of their time pacing (when being observed), with tigers pacing for an average of 16.4% of observed time (Clubb & Mason, 2007). Across all species, the researchers found that the incidence of stereotypic pacing was best predicted by median daily travel distance in the wild and concluded that a wide-ranging natural lifestyle was a major risk factor for poor welfare among carnivores in captivity. This is particularly relevant for Amur tigers, who represent the widest ranging species of all big cats (in some cases ranging over 2,500km2) and are thought to demonstrate a home range size only routinely exceeded by polar bears (Veasey, 2020). A 2023 study supports this initial research and builds on it to conclude that the welfare problems experienced by wide ranging big cats reflect naturally itinerant lifestyles in the wild (Bandeli et al. 2023). This is particularly the case for species whose typical daily travel distances are a small fraction of their annual home range size (Table 3). The inhibition of natural behaviour by the confines of captivity commonly manifests in route-tracing, where a big cat will walk the same repetitive route around its enclosure, often leaving clearly distinguishable paths. The results of the study may underestimate the susceptibility of certain big cats to welfare problems in captivity due to the analysis being at the species level rather than the sub-species level where there is significant variation in home range sizes e.g. tigers.

In the five years to June 2024, 34% of all public concerns submitted to Born Free through its Raise the Red Flag programme relating to big cats in zoos referenced stereotypical behaviour. Concerns related to big cats in 44 European zoos, including 21 in the UK. Of those zoos, 45% were EAZA member facilities.

While pacing is sometimes dismissed by the zoo industry as animals simply patrolling their territory, to claim that this behaviour is replicated in the wild is greatly misleading. From a cognitive perspective, pacing in captivity and walking in the wild are not comparable (Veasey, 2020). With tigers, for example, the behaviour of patrolling their territory involves scent marking and vocalisations to avoid conflict with conspecifics. In the wild, territories do not have fixed boundaries outlined by a paced route but are a continually shifting space used by the tiger (e.g., Liu et al. 2024). Therefore, repetitively pacing the edges of an enclosure, whether the entire perimeter or by a short route, is an artefact of captivity that is not replicated in the wild. Not only are stereotypical behaviours such as pacing a significant welfare concern for the individual, they may also indicate psychological changes that could further limit reintroduction success (Mason et al. 2007).

Fighting between enclosure companions is a common and sometimes fatal outcome resulting from a small exhibit.

HEALTH & SAFETY

As most big cat species are naturally solitary and territorial, the process of introducing animals (even for mating purposes) is high-risk and unpredictable. As such, AZA and EAZA big cat guidelines acknowledge the need for enclosure designs that enable individuals to be separated and prevent any animals from being cornered, in order to mitigate the risk of potentially fatal conflicts that may arise between individuals. In conflict situations where animals cannot escape, and where keeper intervention is difficult or delayed, severe injury or death of captive animals are likely outcomes (AZA Lion SSP, 2012).

Analysis of North American big cat studbooks revealed that almost 300 big cats – many from species that are typically solitary in the wild – have died from injuries caused by unnatural and forced interactions with enclosure companions in a small zoo environment that offers no opportunity for escape (Born Free USA, 2024).

In 2022, a female tiger, Sinda, was killed by a male, Miron, during an attempted breeding introduction at Knowsley Safari Park in the UK.

On New Year’s Day 2023, a male lion killed a lioness in front of visitors at Longleat Safari Park in the UK, with the zoo subsequently claiming that it was “a rare but natural incident” (Bulbul, 2023).

The AZA emphasises that trauma from an enclosure companion is the most common outcome resulting from a small exhibit, which can be fatal for big cats. This trend is not exclusive to big cats in captivity; trauma has been cited as the most frequent and serious cause of health problems in mixed species zoo exhibits, in addition to nutrition-related problems, infectious diseases, and parasitic diseases. Competition for resources, including food and water, resting places, and establishment of territories, may provoke conflict. Efforts by animals to avoid conflict in captive environments may also lead to serious and sometimes fatal injuries (Kaandorp, 2012).

Since 2004, there have been at least 28 incidents of visitors or staff being injured or killed by big cats kept in zoos across Europe. Despite this, there are still some facilities within Europe which allow visitors to enter enclosures with big cats, while others offer a range of non-contact ‘experiences’ (Taigan Park, 2024). Big cats that escape their enclosure are often killed to eliminate any risk to the public, zoo staff or other animals. Most recently at Dudley Zoo in the UK, a snow leopard, named Margaash, was shot dead in November 2018 after a keeper left an enclosure door open. In an attempt to limit such tragic incidents, zoos frequently implement safety measures to mitigate these risks that also negatively impact big cat welfare, including confining them to smaller indoor enclosures overnight.

PUBLIC REPORT 2023 

UK:

“I am highly concerned for the welfare of the tigers in this zoo. I saw two tigers living in a small living space without any sort of stimulation that had driven them both mad; to the point thatthey were both continuously pacing back and forth in the same place of their enclosure. It had created a path in that area because they had walked up and down for such a long time. Their mental condition showed clear signs of distress and depression, even children who were watching them were instantly concerned for their welfare and asking parents if theywere okay and if they were sad.”

CASE STUDY: BLAIR DRUMMOND SAFARI PARK LIONESS DEATHS

RESULTING FROM BREEDING INTRODUCTIONS

In June 2021, a whistleblower at Blair Drummond Safari Park, UK, reported the death of two lionesses in 2016 following an altercation with Zulu, a male member of the group (Norton, 2021). Zulu was moved to Blair Drummond Safari Park from Emmen Zoo, Netherlands, in February 2016.

On 6 June 2016, Saskia, a 20-year-old lioness, was bitten through her spine by Zulu, and was subsequently euthanised (The Scotsman, 2016). According to the whistleblower’s reports, the lioness “had a hole in its back with a fractured bone for 23 days before it was euthanised”

Just a month later, Makalu, another lioness, was also attacked by Zulu. According to the report, she had “her oesophagus ruptured and was left all

day before being euthanised once the park closed”. The report also alleges that Saskia’s death was announced to the public as the attack happened in front of visitors, but Makalu’s death went unannounced at the time.

While it is true that such fatal incidents occur in the wild, risks are heightened in captivity due to a lack of opportunity for animals to escape, find new territory or choose who they do and do not associate with. Even when careful introduction procedures are in place, taking such risks for the purposes of breeding more animals for captivity has serious potential animal welfare consequences and serves no clear conservation purpose.

CAPTIVITYRELATED HEALTH ISSUES

Big cats are known to suffer from a number of health issues. While some occur in free-living big cats, they are typically exacerbated by the artificial nature of and limitations inherent to the zoo environment. Some health problems are exclusive to captive animals.

Infectious diseases

Infectious diseases can result from direct or indirect contact with existing or introduced animals, exposure to people, or environmental factors. A review of the available literature by Green et al. (2020) identified a total of 63 pathogens recorded in both wild and captive lions, most of which were parasites (56%), followed by viruses (27%) and bacteria (17%). Reported examples of viral infections include Feline Infectious Peritonitis (FIP), Feline Immunodeficiency Virus (FIV), Feline Leukaemia Virus (FeLV) and Canine Distemper Virus (CDV). Big cats are also susceptible to and can transmit zoonotic diseases, such as tuberculosis, rabies, and toxoplasmosis, as well as various parasitic diseases. These infections can sometimes result in high levels of mortality in captive situations (Shrivastav & Singh, 2017). In 2018, two lions at Paignton Zoo, UK, Maliya and Indu, were reportedly euthanised after they contracted tuberculosis (Radio Exe, 2018).

Although high disease-related mortality rates in captive big cats may to some extent reflect longevity, they may also be explained by stress-induced immune system suppression and the difficulty in separating infected and non-infected individuals in captivity. Big cats in zoos live in close proximity to animals that they would not usually encounter in the wild, which may expose them to infectious diseases they would otherwise not normally encounter, such as cowpox which has been identified in snow leopards and a tiger in UK zoos (Costa et al. 2023). Cheetah populations in zoos are known to be susceptible to multiple infectious diseases that do not commonly affect wild populations (Terio et al. 2018). Underlying disease was identified as a likely factor in high infant mortality rates among jaguars in the European breeding population between 1998-2018 (Duque-Correa et al. 2022).

During the Covid-19 pandemic, a number of zoos, including European facilities, reported Covid infections in various big cats, highlighting the vulnerability of animals in the zoo environment to human infections through close proximity to keepers or the wider public. All big cat species seem to be susceptible. Infection has resulted in clinical disease and, in some cases, death of affected animals (Hosie et al. 2021).

Mitigation of infectious disease risks requires strict biosecurity controls, quarantine procedures, vaccination programmes, regular health monitoring, close control over nutritional and environmental management, the appropriate education and training of staff, and access to specialist veterinary services. The degree to which these measures are effectively implemented by zoos varies widely. However, even with such measures in place, infectious diseases remain a significant concern for big cats in zoos.

Underlying disease is a likely factor in high infant mortality rates among jaguars in European captive breeding programmes.

© Tambako

The Jaguar, Flickr creative commons

CASE STUDY: BIG CATS AND COVID19

While the coronavirus pandemic highlighted the financial vulnerability of zoos when forced to close their doors to the public for extended periods, and resulted in some threatening to have to kill their animals in an attempt to secure funding, the virus itself posed an additional threat to the welfare of captive big cats.

There have been many reports of big cats in zoos contracting Covid-19 across the globe, infecting all seven big cat species. In many cases, the big cats reportedly suffered mild symptoms or were asymptomatic. However, several zoos, particularly outside of Europe, reported that their big cats had died as a result of complications from Covid-19. One example was a 17-year-old female tiger at Borås Zoo, Sweden, who was reportedly infected with Covid-19 and euthanised

after she lost her appetite and her condition deteriorated (SVT, 2021). The male tiger and two lions at the same zoo also tested positive for Covid-19 and showed mild respiratory symptoms.

In many cases of big cats testing positive for Covid-19, it is thought likely they contracted the virus from infected zoo staff (BBC, 2020).

While Covid-19 may not pose a substantial threat to captive big cat populations, it serves as an example of how big cats in zoos succumb to diseases that they would be unlikely to encounter in the wild due to their unnatural proximity to humans and other animals in zoos. It also highlights the future risk that emerging zoonotic diseases may pose to captive wild animal populations and humans alike.

© Daniel Sjostrom, Flickr creative commons

Psychological disorders

Stress and anxiety in zoo-housed big cats can result from a lack of mental and physical stimulation, inappropriate social groupings, and proximity to other animals and people. This can lead to lethargy, reduced appetite and withdrawn behaviour. In many cases it can also lead to the development of stereotypical behaviours (see Stereotypical Behaviour above). Such behaviours are common in big cats kept in a zoo environment (Mason & Rushen, 2006). Born Free’s co-founder, Bill Travers, coined the term ‘zoochosis’ for these behaviours, reflecting the fact that they are commonly associated with the keeping of wild animals in zoos but are never seen in the wild.

Management-related health issues

Limited space for exercise and unnatural feeding schedules can lead to excessive weight gain. A recent study of carnivores in European zoos found jaguars in particular to have higher than ideal body condition scores (Kleinlugtenbelt et al. 2023). Obesity in big cats can result in a range of health issues such as diabetes, cardiovascular problems, and joint disorders. While zoos may attempt to mitigate these issues through dietary management and enrichment activities to encourage physical activity, the zoo environment often limits the effectiveness of these measures.

Big cats in zoos also frequently suffer musculoskeletal problems such as arthritis and muscle atrophy, as a result of restricted movement and lack of opportunity to engage in normal activities such as hunting. Dental problems, including plaque buildup, periodontal disease, and broken teeth, are also common, reflecting the fact that diets for big cats in zoos do not mirror the diet they would experience in the wild (Whitten et al. 2019).

Captive tigers have been reported to suffer from gastrointestinal syndromes resembling chronic inflammatory bowel disease collectively referred to as ‘general adaptation syndrome’ or ‘tiger disease’, which is thought to be stress related.

Diet and feeding

A number of systemic bacterial diseases introduced through raw meat have been identified in tigers living in zoos, which can result in fatalities especially in tiger cubs. Salmonellosis, caused by Salmonella typhimurium, which occurs either sporadically or as outbreaks, is a recognised medical problem in tigers. To prevent salmonellosis in tigers, the AZA in North America recommends that there should be quality control at the production source of raw meat intended for big cat consumption, the diet should be maintained frozen prior to feeding, and the thawing process and feeding method must reduce possible contamination.

Many zoos use less labourintensive and less enriching feeding methods.

While zoos may be able to meet big cat nutritional needs, they are less able to address their vital psychological feeding needs (Veasey, 2020). Feeding-related behaviours are important for individual animal welfare, since such cognitive processes are essential for survival in the wild. However, a recent study found that of 44 European zoos sampled, most were observed using less labour-intensive and less enriching feeding methods and none reported methods that require social carnivores to cooperate to access food (Kleinlugtenbelt et al. 2023).

As well as psychological impacts, different feeding methods in captivity compared to those big cats employ in the wild have resulted in morphological differences. Big cats in zoos have significantly lower bone density compared to their wild counterparts, likely because of a lack of opportunity for activities such as hunting, subduing prey and swimming (Chirchir et al. 2022). The zoo environment also affects the morphology of big cat skulls. Captive lions and tigers have different shaped skulls and mandibles compared to their wild counterparts, a differentiation which may be driven by wild big cats needing to kill, manipulate and consume large prey (Cooper et al. 2023). Despite these species being sexually dimorphic, one study found nearly twice as much skull shape variation among zoo-housed big cats as sexual dimorphism (Hartstone-Rose et al. 2014). While the drastic differences in diets and feeding methods are likely to have caused these morphological differences, inbreeding could also be a factor.

Inbreeding

Genetic health problems are a significant concern due to the limited gene pool available in captivity. Inbreeding can lead to a higher prevalence of hereditary conditions in big cats such as hip dysplasia, heart defects, and compromised immune systems. In spite of the existence of zoo industry-coordinated breeding programmes such as the European Ex-situ Programme (EEP) and the Species Survival Plan (SSP) programme in North America, the limited number of individual animals and the logistical challenges of moving animals between facilities limit the ability of these programmes to maintain genetic diversity among captive big cat populations.

White lions and tigers are commonplace in zoos around the world, with zoological institutions often describing them as ‘rare’, often implying that they belong to a distinct subspecies (Dean, 2019).

Rather than being a ‘rare’ subspecies, these animals are, in fact, colour morphs. While white colour morphs do occur occasionally in the wild, they are few and far between. In the zoo industry, because white lions and tigers draw visitors, multiple generations have been created by deliberately breeding family members who express this genetic anomaly. As such, white lions and tigers in zoos are, by default, inbred.

In recent years, zoo associations have tried to distance themselves from this unethical practice, which has resulted in physical deformities and illness in the inbred animals exhibited by their members and other zoos around the world (EAZA, 2013). Despite EAZA releasing their position statement in 2013, stipulating that EAZA members should not engage in breeding practices which

PUBLIC REPORT 2024

UK:

“It’s the first time I've visited *** zoo, I've never been so disgusted in the upkeep of wild animals. The environment they’re kept in isn't big enough for them, the tigers looked in poor condition and were just pacing back and forth.”

Figure 3: A white tiger at the Bratislava Zoo, Slovakia, in 2019 demonstrating strabismus (crossed eyes), a common health issue associated with genetic inbreeding.

© Tambako The Jaguar, Flickr Creative Commons

Multiple generations of white lions and tigers have been deliberately bred by zoos

intentionally result in rare recessive alleles (often caused by inbreeding), Magdeburg Zoo, Germany, bred white lions in 2017 and Tbilisi Zoo, Georgia, a candidate for EAZA membership, also bred white lions in the same year.

Inbreeding is not only an issue for white lions and tigers. While the white colour morphs provide a clear visual confirmation of inbreeding practices in zoos, studies have shown severe inbreeding in wider big cat zoo populations. A study carried out in 2017 on the Asiatic lion population at ZSL London Zoo found that decades of inbreeding from one founder population of just 9 lions led to the premature death of 39 of the 57 cubs born there. The study examined the genetic diversity of the founders of the European captive population of Asian lions and concluded that the European Studbook for the Asian Lion shows that the EEP founder population contains individuals from matings of full and half siblings, including all female founders, and this was likely responsible for high levels of stillbirths and infant mortality (Atkinson et al. 2018). Another UK zoo, Longleat Safari Park, was reported to have killed five of its lions – a mother and her cubs – due to aggressive behaviour allegedly caused by inbreeding (ITV, 2014).

Concerns over inbreeding of big cat populations in captivity are not new. Articles dating back almost 40 years sounded alarm bells following research investigating reproductive success of both free-living lions and lions in captivity, with warnings for captive populations (Wildt et al. 1987). Previous research on leopards in zoos found that the proportion of inbred specimens within EEPs was 28.6% for the Persian leopard, 24.7% for the Amur leopard and 13.1% for the North-Chinese leopard (Sternicki et al. 2010). Inbred big cats experience higher mortality rates, shorter lifespans, and birth defects, among other issues. Inbreeding also undermines the credibility and potential of any captive breeding programme to contribute to the conservation of wild populations of big cats via reintroductions.

“ZOOTHANASIA”

The Royal College of Veterinary Surgeons (2024) defines euthanasia as “painless killing to relieve suffering”. Referred to euphemistically as “good death,” true euthanasia is carried out only in the interests of the animal, without consideration of other factors such as perceived usefulness to humans or lack of space or capacity to care for them (Bekoff, 2018). In zoos, animals may be euthanised for genuine reasons to prevent suffering or to expedite an inevitable death.

However, they may also be subject to so-called “management euthanasia” or “culling”. This euphemistic and misleading use of the term means to kill healthy animals deemed surplus to requirements specified by the zoo, such as lack of available space, low perceived entertainment value, low breeding value, or financial reasons. It has been estimated that a total of 1,094 cheetahs, tigers, and Amur leopards were ‘euthanised’ across North American zoos between 1967 to 2019. In 2014, the then Executive Director of EAZA Dr Lesley Dickie estimated that between 3,000 and 5,000 animals are killed/culled every year in zoos across Europe for management purposes (Barnes, 2014). It is worth noting that prior to the controversial culling of Marius the giraffe by Copenhagen Zoo, Denmark in 2014, which drew worldwide criticism, EAZA did not have an official publicly available policy on culling; just a euthanasia policy. A separate management euthanasia/culling policy was introduced in 2015, and was updated in 2023 (EAZA, 2023c). “Management euthanasia/culling” is defined by EAZA as “the removal of animals from a population in human care, for non-medical reasons, by humane killing carried out by appropriately qualified and experienced staff”.

“EAZA CONSIDERS THAT MANAGEMENT EUTHANASI A/CULLING MAY BE APPROPRIATE WHERE:

1. The only alternative is permanent transfer to accommodation which cannot assure a proper level ofwelfare for the animal, and which cannot be improved within a short interval agreed by the responsible EAZA authority.

2. The continued presence of an individual animal is unreasonably disruptive to a functioning social group within an individual collection.

3. The maintenance of a population’s demographic or genetic viability is at risk through the continued presence of one or more individual animals.”

Management euthanasia/culling might be used in cases when zoos have deliberately or unintentionally bred animals who are then deemed to be of the wrong genetic lineage (overrepresented, inbred, or otherwise undesired by the zoo), to enable female animals to breed once more after the offspring in her care are killed, when an individual is causing management issues in their social group, when animals escape or otherwise are considered dangerous, when an animal’s only remaining companion is euthanised (e.g. lions), or if there is overcrowding in the limited space provided by zoos. Importantly, the circumstances for management euthanasia/culling can directly be traced to the way zoos hold animals captive, manipulate their breeding practices, or fail to properly secure them and thus create dangerous situations for staff and visitors.

Examples of big cat deaths in European zoos being inappropriately described as “euthanasia” include:

-A female lion was shot and killed after an escape caused by human error in a Belgian zoo in 2018. A headline in the Associated Press read “Lion euthanised after escape in Belgian Zoo” (El-Touni, 2023).

-In 2015, Odense Zoo, Denmark, killed a healthy nine-month-old female lion because they “had too many female lions” (King, 2015). Some news articles described the lion as having been “euthanised” (Macias, 2015).

-Nine lion cubs were killed by Borås Djurpark in Sweden between 2012 and 2014. The zoo continued to allow the parents to breed in the knowledge that the cubs, all reported to be in excellent health, would be killed. The zoo released a statement referring to the killing as “euthanasia” (People, 2018).

-In 2018, a snow leopard escaped his enclosure after a zookeeper left the enclosure door open at Dudley Zoo, UK, and was subsequently shot dead. Responding to the news, the zoo director at the time said, “Euthanasia is, and always will be, a last resort” (BBC, 2018).

-In 2017, it was reported that South Lakes Safari Zoo, UK, had seven "healthy lion cubs euthanised because the zoo did not have space to house them" (BBC, 2017).

CASE STUDY: COPENHAGEN ZOO KILLS LION FAMILY TO MAKE WAY FOR YOUNGER BREEDING MALE

The same Copenhagen Zoo, Denmark, which faced worldwide criticism for killing Marius the young giraffe and feeding him to their lions, also killed four lions in 2014 (BBC, 2014). This included a 16-year-old male, a 14-year-old female and their two 10-month-old cubs that the zoo failed to rehome. They were all killed to make way for a new three-year-old male lion, who would likely not be accepted by the current older male (The Guardian, 2014b). The older adults were killed because the zoo wanted to avoid the new male lion breeding with the older female and avoid the risk of the older male breeding with his offspring that were born in 2012. As their 10month-old cubs were too young to fend for themselves, they were also killed.

The zoo was reported to have issued the following statement: "...because of the pride of lions' natural structure and behaviour, the zoo has

had to euthanise the two old lions and two young lions who were not old enough to fend for themselves" (The Guardian, 2014a). This serves as another example of zoos misleadingly using the term “euthanasia” to describe the killing of healthy animals for management purposes.

While the zoo rightly faced a lot of criticism, it should be noted that their culling policies are by no means unique, with many other European zoos making similar decisions. Copenhagen Zoo was different in that it openly admitted what it was doing, and why. Given the strong negative public reaction to such reports, it is very likely that other zoos avoid making such decisions public. While this particular, widely reported incident happened ten years ago, zoos across Europe continue to kill healthy animals for management purposes.

© Jo-Anne McArthur, Born Free

Close contact feeding activities can result in animals becoming habituated to humans and seeing them as a source of food.

EXPLOITATION OF BIG CATS

In addition to the many health and welfare issues experienced by big cats in zoos as a result of life in captivity, many continue to be exploited across Europe for special visitor close encounters, experiences, and other activities.

These activities are sold at varying prices, some zoos charging hundreds of pounds to spend a short time close to, and even in direct contact with, big cats. Many zoos market these opportunities as important activities that they claim raise funds for conservation, while other zoos simply promote the chance to get ‘up close and personal’ with your favourite animal.

Of the 51 zoos in the UK that currently hold big cats, 43 offer some sort of specific visitor experience or special encounter with them. Visitor feeding experiences in zoos are particularly common and often involve feeding big cats small pieces of meat through the enclosure fence, using unnatural methods of offering feed involving hands, sticks, or tongs. At some facilities, a number of visitors will partake in the experience daily, meaning that big cats are regularly fed small pieces of meat at times of day which may be different to when they would naturally consume food in the wild. While it may be profitable for the zoo, this is contrary to the natural feeding habits of big cats in the wild, where they do not hunt and consume prey every day, with larger kills sustaining them for several days. Close contact feeding activities are likely to result in animals becoming habituated to humans and seeing them as a source of food. The regular feeding of big cats at set times of day can also result in anticipatory and stereotypical behaviours in zoo-housed big cats; particularly pacing in the area of the enclosure where such experiences usually take place.

HUNGARY:

“There were a lot of big cats, some of which were kept in incredibly small spaces, barely enough to stretch their legs. The two lions were in a very small space, and it seems the animals are being exposed as an attraction rather than giving them a proper home in captivity. It was very sad to witness. The big cats were constantly pacing back and forth and sometimes growling at customers. I noticed that a panther’s cage was really dirty as well.”

Regular keeper talks about big cats take place at many zoos, often daily. These activities can attract crowds of visitors, many lining up by or surrounding an enclosure. Significant noise levels can result from visitor shouting, laughing, and clapping. In addition, keepers may use microphones and speakers during their talks, which creates additional noise and potential stress for the cats, most of which are naturally shy and elusive.

In recent years, some zoos have made headlines after offering activities involving their big cats. In 2019, Dartmoor Zoo, UK, offered visitors the opportunity to play “tug-of-war” with their lion and tiger for a fee of £15 (BBC, 2019). This example of zoos using big cats for unnatural, ‘entertaining’ performances and interactions for commercial gain was met with widespread condemnation at the time. While these tug-of-war activities may not necessarily be detrimental to animal welfare if appropriately supervised and scheduled, such activities do not engage “...[the animal’s] natural instinct to hunt”, as the zoo apparently claimed, or replicate any natural hunting behaviours such as locating, chasing, catching, holding, immobilising or killing prey. Many of these behaviours are impossible to replicate in a zoo setting regardless of the method of food provision.

Some European zoos appear to breed big cats specifically for the purpose of supplying animals for visitor petting and photo opportunities. Although some zoos may claim that cubs have been rejected by their mother, they may also be deliberately separated from maternal care and hand-reared to habituate them to human contact and handling. This enforced separation is likely to cause significant stress to both mother and cub. The premature removal of cubs will bring their mothers back into oestrus, so she can be quickly bred again to produce another litter.

The repeated petting, handling, and touching of big cat cubs has serious welfare implications for the animals involved. Such interactive activities often involve large crowds of people with animals passed from person to person throughout the day and exploited purely for financial profit.

The fate of these cubs as they grow and typically become too dangerous to handle, at around six months old, is highly uncertain, given the lack of available space across zoos.

CASE STUDY: USE AS COMMERCIAL ENTITIES FOR VISITOR EXPERIENCES

Paphos Zoo, Cyprus

Magán Zoo, Felsőlajos, Hungary

During a past visit to Magán Zoo, Born Free observed the use of two lion cubs, around two months old, who were introduced to a group of visitors who had congregated next to an enclosure exhibiting an adult male and female lion. The cubs were observed being passed from person to person for over an hour, the cubs were stroked, cuddled, and held for photos.

Today, Magán Zoo states on their website (translated from Hungarian) that “Periodically, usually every year – in the case of the birth of a cub, it is possible to hold and feed brown and white lions, Siberian and white Bengal tigers, several times a day”.

Paphos Zoo has attracted both local and international attention over the years with concerns for the welfare of many animals, the size of their enclosures, and lack of environmental enrichment being consistently flagged.

The zoo has a history of breeding large numbers of tigers and lions, many of which have been used for visitor interactions. Their website states ”all animal interactions can be arranged during your visit at the various animal enclosures. These are available throughout the day, every day. Cash only!”

Visitor reports sent to Born Free have described seeing both lion and tiger cubs being exploited, with visitors being charged 20 euros to cuddle, bottle-feed and pose with cubs for a photo. With a seemingly continuous stream of cubs being born at Paphos Zoo, their long-term future and welfare is uncertain. In December 2023, two young Siberian tigers born at Paphos Zoo were reportedly sent to Darjeeling Zoo, India in exchange for two red pandas. Since 2008, it is understood that more than 20 tiger cubs have been born at the zoo and sent to other zoos and captive animal facilities around the world.

Wildlife Park, Rabat, Malta

Wildlife Park states on their website that they offer visitors unique ‘close encounters’ and ‘interactive experiences’ with their animals. Visitor reports sent to Born Free have described their experience of seeing a tiger cub used in close encounter sessions at Wildlife Park for 25 euros. The cub appeared distressed by the way it was handled by a staff member before being presented for bottle-feeding and petting.

Concerns about zoos in Malta have been in the spotlight for many years. In 2020, draft regulations on the keeping of wild animals in zoos were released by the Maltese Government that included a ban on the handling and petting of zoo animals. However, just a day later this draft was amended to allow these activities to continue, as long as they are carried out under the supervision of the zoo’s vet. Four years later, Malta’s ‘Keeping of Wild Animals in Zoos Regulations’ have yet to pass into law.

CONSERVATION IMPACTS OF CAPTIVE BREEDING

National Geographic (2024) defines wildlife conservation as “...the practice of protecting plant and animal species and their habitats”, while the United Nations Convention on Biological Diversity (2006) defines in situ conservation as “the conservation of ecosystems and natural habitats and the maintenance and recovery of viable populations of species in their natural surroundings and, in the case of domesticated or cultivated species, in the surroundings where they have developed their distinctive properties”. Conservation strategies include ecosystem-based or species-centred approaches, as well as protecting land areas, restoring critical habitat, reintroducing or translocating species, mitigating conflict between people and wildlife, preventing and controlling invasive species, and addressing other factors which result in the decline of wildlife populations or habitats. Zoos and aquariums accredited by EAZA claim to be “conserving all populations of a species both within their natural range and outside it” in what is called the “One Plan Approach” (EAZA, 2024). EAZA claims its member zoos “work to ensure that many of the most endangered species populations in our zoos and aquariums are intensively managed to ensure their survival”. However, the problem with managing captive populations is that the vast majority of captive animals are never released into the wild, bringing into question the conservation value of any One Plan Approach and the claim made by the zoo community that the maintenance of captive animal populations directly contributes to wildlife conservation.

According to their website, 164 EAZA-accredited facilities provided financial support totalling €23.7 million (£20.2 million) to in situ conservation in 2022 (EAZA, 2023b). This equates to an average financial contribution of £123,170 per facility. In comparison, the Welsh Mountain Zoo, UK, announced the redevelopment of their snow leopard enclosure in 2021 at a cost of £1 million (Kendrick, 2021). In 2019, Twycross Zoo, UK, spent £1.5million to construct a new Sumatran tiger enclosure (Bisknell, 2019). Historically, ZSL London Zoo, UK, spent £5.2 million on its Asiatic lion enclosure which was completed in 2016 and £3.6 million on its tiger exhibit in 2013. While Zoo Halle, Germany, spent £8.45 million on their big cat house to keep jaguar, lions and tigers in 2003 – none of the enclosures exceeded 400m2 (Klein, 2015).

Between 2018 and 2022, it is reported that felids were the 4th most supported taxa by contribution from EAZA members (EAZA, 2023a). However, aside from staff time and financial support, it remains unclear what meaningful conservation benefit zoos have provided to big cat species in the wild. Previous analysis of the UK’s 13 larger charitable zoos found that on average just 4.2% of their total annual income, or just 6.6% of the

money they received from admission fees, went towards in situ conservation. This was despite those zoos having a combined income which exceeded £181 million. Determining the level of funding that was spent directly on field conservation also proved difficult; the financial records of the charitable zoos, which are published annually, were often vague on exactly how expenditure marked as “conservation” was allocated, and often included the care costs of animals kept within the zoo. Despite zoos advocating for the One Plan Approach, when it comes to financial expenditure, the primary focus appears to be on maintaining the zoos themselves.

Globally, even the most supportive zoos typically only allocate between three to five percent of their budget to conservation work (Born Free, 2021; Critser, 2024). The relatively small amount dedicated to big cat conservation by European zoos suggests that genuine conservation contributions are at best a distant second to most other zoo expenditure on the likes of construction and maintenance. The reality is that, in large measure, zoos exist to exhibit animals to the public for their entertainment. It should not be surprising that most of their budget is allocated to maintaining these animals on display.

As has been noted previously, very few captive big cats are ever released into the wild. According to the International Cheetah Studbook, four captive cheetahs were released in 2019 by the Cheetah Conservation Fund (Marker & Johnston, 2019). Further analysis of the studbook, from the first individual to the last listed (~1969-2019), revealed that just 52 out of 10,072 (<1%) recorded individuals were released at some point during their lifetime between 1996 and 2019. Of these, 15 were re-captured and died in captivity, three were re-released after being re-captured, and 34 remained in the wild. Of these animals, 75% (39 individuals) were originally captured from the wild, and 25% (13 individuals) were captive-born. Three of these were lost from the studbook’s records at some point; one after being recaptured and transferred, one after being released and recaptured, and one after being released, recaptured, and transferred.

An issue of Zooquaria, the quarterly publication of EAZA, highlighted how the reintroduction success for large carnivores bred ex situ is doubted, but could “be successful if the animals are raised with a minimum of human contact and are well socialised and well trained not only in hunting skills, but also in coping with novel situations” (Hartmann et al. 2016). However, the typical zoo environment does not meet these criteria. The online EAZA Conservation Map (https://map.eaza.net/ ) lists projects supported by EAZA member zoos from 2015 onwards and at the time of writing, only one reintroduction project appears to have used big cats born at a zoo, specifically two cheetahs transferred from Howletts Wild Animal Park, UK, to a South African private game reserve in 2021. Despite the high numbers in captivity and dwindling wild populations, to our knowledge there have been no other successful reintroductions carried out by zoos for any other big cat species born in a European zoo.

It remains unclear what meaningful conservation benefit zoos have provided to big cat species in the wild.

Animals raised in zoos often show a loss of natural behaviours associated with optimal fitness in the wild.

In contrast, in efforts to maintain a sustainable level of genetic diversity within the captive tiger population, wild-caught Amur tigers (e.g., orphaned cubs or “conflict tigers” who could not be released for reasons otherwise unspecified in the studbook) periodically enter the Eurasian Regional Association of Zoos and Aquariums (EARAZA) tiger programme and provide opportunities for “occasional genetic supplementation of the Amur tiger ex situ global and regional populations.”

In 2019, the US-based NGO, In Defense of Animals, exposed reports of Russian zoo officials removing young Amur tigers from EARAZA zoos and illegally trafficking them to buyers in China, Kazakhstan, and other unknown locations. Russian zoos were also reported to have sent tigers to zoos with troublingly high death rates, and with no further record of those animals existing from that point on (IDA, 2019). Along with the AZA, EAZA, and the Japanese Association of Zoos and Aquariums (JAZA), EARAZA remains one of the many zoo associations that make up the World Association of Zoos and Aquariums (WAZA) and is responsible for maintaining studbooks to actively manage ex situ programmes for Amur tigers, as well as participating in the Global Species Management Plan for tigers (WAZA, 2023).

The hand-rearing of big cats, as practiced by some zoos when natural rearing fails, directly conflicts with any potential conservation reintroduction possibilities. Depending on the species, hand-rearing big cat offspring has resulted in the production of fewer cubs by hand-reared individuals (as demonstrated in Siberian tigers, snow leopards, and male cheetahs), later-onset reproduction (female snow leopards), shortened lifespan (female Siberian tigers), and higher infant mortality (snow leopard and male cheetahs) when compared to parent-rearing (Hampson & Scwhitzer, 2016). Further, behavioural issues later in life due to a lack of appropriate socialisation during critical learning years can negatively impact survival and breeding in the wild when release is the ultimate goal. Proper socialisation can take up to three years in large carnivores, and failure to develop the appropriate behavioural repertoire can result in the development of inappropriate aggression or fear of conspecifics, inability to engage in play, difficulty in reproducing, inappropriate care of offspring, and an unnatural fixation and dependence on humans, which can be particularly damaging to big cats threatened with poaching or retaliatory killing in the wild (Hampson & Scwhitzer, 2016). Prior to the passage of the Big Cat Public Safety Act in the U.S. in 2023, big cats had been intentionally hand-reared by some zoos to facilitate their use as photo props long-term, as hand-reared animals are more habituated to humans than those naturally reared (D’Cruze et al. 2019).

Less than 1% of recorded individuals in the International Cheetah Studbook were released into the wild between 1996 and 2019.

Even when not hand-reared by humans, the negative effects of spending time in captivity and unnatural exposure to humans often counteract efforts to maximize animal survival in the wild post-release. Animals raised in captivity often show a loss of natural behaviours associated with optimal fitness in the wild, including a decreased ability to forage/hunt, deficiencies in social interactions, issues with breeding, nesting, and locomotory skills, differences in morphological features, lack of immunity to viruses/diseases prevalent in their wild counterparts, and habituation to humans which can lead to conflict with local communities, postrelease. In a study that examined how captivity may affect the survival of reintroduced carnivores, the researchers determined that reintroduction projects using wild-caught animals were significantly more likely to succeed than projects using captive-born animals. Across 17 species, the results indicated that reintroduced captive-born carnivores were particularly susceptible to starvation, unsuccessful predator/competitor avoidance, and disease (Jule et al. 2008).

To increase the number of big cats in the wild, one of the most valuable and common strategies, as indicated by the Lion Recovery Fund (2022), is to invest in the protection of existing populations. However, in some cases, investing in the reintroduction of lions to sites from which they have disappeared can also be beneficial. According to the Lion Recovery Fund’s recommendations, the main factors to consider before conducting a reintroduction of lions include that the release site is suitable, the factors that caused the original lions to disappear have been addressed, and the lions intended for reintroduction are genetically and behaviourally viable.

The global captive population of lions, however, presents an undeniable challenge regarding the need for genetic viability. A study published in 2022 summarising four decades of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES)trade data on live individual lions reported to have been imported across international borders into lion range states identified 1,056 individuals with a potential risk of interbreeding with wild lions, 73% (772 individuals) of whom were captive sourced. The IUCN (2013) defines translocation as “...the human-mediated movement of living organisms from one area, with release in another”. Using an independently developed scoring system to determine suitability for conservation translocations, only 7% of the translocated individuals were “first choice" and 73% were "no option" to promote genetic sustainability. These results suggest that a sizeable percentage of lions bred in captivity and translocated long-distance for facilities including zoos, private collections, game reserves, and hunting concessions, are at risk of future interbreeding and thus cannot benefit genuine conservation efforts on a meaningful level. Further, captive populations have historically been actively inbred by zoos, having been artificially selected for certain desirable phenotypic traits and behaviours that facilitate habituation to humans and training in captivity, consequently making captive lions poor candidates for release into the wild (Bertola et al. 2022).

© A Ticer

Established with the support of the Born Free Foundation in 2004, the Satpuda Landscape Tiger Partnership aims to reduce threats facing tigers in India, and to promote human-tiger co-existence across a vast multiuse landscape. Since its inception, it has successfully contributed to a steady increase in India’s tiger population and seen the number of protected Tiger Reserves increase to 53, covering over 75,000km2 Additionally, the project works to reduce conflict between tigers and local communities through education and conservation awareness programmes, and by reducing the likelihood of tiger attacks on livestock through the implementation of livestock feeding methods which reduce the need for farmers to graze their cattle in forests where most attacks occur.

A review of multiple plans for improving the conservation status of big cats in the wild via reintroduction programmes confirms that the following actions are frequently listed as integral for success: protecting habitats; providing proper land management of all protected areas; ensuring that habitat will support viable population sizes of co-predators, prey species, and conspecifics; only allowing ecologically compatible land use within the protected habitat; providing corridors that link one protected area to another to allow for dispersal to connect fragmented populations; enhancing coordination across reserve boundaries; addressing concerns of local people/sources of human-animal conflict; and monitoring the animals post-release (Qin, 2015; Bulatkulova, 2022; NTCA, 2024). None of these programmes cite captive breeding as a critical action for a successful reintroduction programme.

The North American regional tiger studbook identifies the poaching of tigers and their prey, habitat loss, and human land use as primary threats to wild Amur tiger populations, and also acknowledges that antipoaching, habitat protection, and other in situ conservation efforts enabled the wild population to expand from an estimated 20-30 individuals in the 1930s to 400-500 tigers in 2005 by mitigating some of these threats (Traylor-Holzer, 2013). It is made clear in the AZA studbook itself that while ex situ captive breeding efforts coordinated by zoos involved in the SSP have resulted in zero introductions of tigers to their natural habitat and thus no positive change in their conservation status in the wild, in situ efforts targeted specifically to address the environmental and human-based threats that pose the highest risk to wild tigers have accomplished significant population increases and thus improved Amur tiger conservation in the wild. Similarly, tigers have not been reintroduced to the wild by any European zoos. Conservationist, Billy Arjan Singh, famously reintroduced a hand-reared tiger he acquired from Twycross Zoo in the UK to the Dudhwa National Park, India in 1976, however the fate of the tiger remained undetermined, including whether it successfully reproduced (Menon, 1997). The fact that in situ conservation efforts can increase a fragile population size by more than 25% in 75 years, while zoos have made no observable positive change for the same species through the keeping and breeding of animals in captivity over the same period of time (or longer), brings into question the ‘conservation’ value of maintaining and breeding big cats in zoos.

The captive breeding of jaguars is not identified as a required conservation action by the IUCN.

LEGISLATION

Legislation impacting big cats in zoos across Europe varies greatly between countries. However, regardless of an individual animal’s location, the legislation which covers their welfare and management is typically broad and non-specific, if it exists at all.

EU ZOOS DIRECTIVE

Zoos situated within European Union (EU) Member States must comply with Directive 1999/22/EC, also known as the EU Zoos Directive. Most notably, Article 3 states that amongst other measures, zoos must, “[Accommodate] their animals under conditions which aim to satisfy the biological and conservation requirements of the individual species, inter alia, by providing species specific enrichment of the enclosures; and maintaining a high standard of animal husbandry with a developed programme of preventive and curative veterinary care and nutrition”. Additionally, Article 4 of the Directive states that, “Member States shall adopt measures for licensing and inspection of existing and new zoos in order to ensure that the requirements of Article 3 are met”.

Prior to its adoption in 1999, only five of the then 12 EU Member States had specific legislation regulating zoos (Belgium, Denmark, France, Spain and UK) (European Commission, 2018). The aim of the Directive was "to ensure that all European zoos meet minimum harmonised standards for the keeping of wild animals and for public safety, in order to facilitate the application of EEC legislation on nature conservation". Where no prior regulations existed, it was intended for the Directive to be transcribed into national legislation to ensure Member State compliance.

A recent evaluation of the Directive found that within the sampled Member States, the most commonly identified breach during inspection processes was related to animal accommodation and husbandry (European Commission, 2018). Concerningly, the evaluation also highlighted that there is great variation in the implementation and enforcement of the Directive across Member States, and the “skills of zoo inspectors are generally broad and not necessarily focused on wild fauna, species-specific issues or conservation”. Furthermore, the evaluation uncovered that several Member States were yet to identify and inspect all facilities which may fall under the Directive’s scope.

The outcomes of the evaluation, some 20 years on from the Directive’s adoption, raises serious concerns for the welfare of big cats in zoos within EU Member States, in regard to the specificity of regulations which outline minimum welfare standards, and the mechanisms to identify welfare issues and effectively correct them.

Non-EU Member States

Only just over half of European sovereign states are members of the European Union (27/50). Therefore, 23 states are not obligated to meet the requirements of the EU Zoos Directive and the majority of these states are believed to have at least one zoo. While some of these states have adopted regulations relating to zoos, often contained within the nation’s legislation relating to animal welfare, others simply require a zoo to obtain a licence with no mandatory welfare criteria, and some have no provisions whatsoever.

©

Jo-Anne McArthur for Born Free

ZOO LICENSING ACT 1981

Within the UK, facilities other than pet shops that keep wild animals and are open to the public for seven or more days within a calendar year require a licence under the Zoo Licensing Act 1981 (as amended). The Act outlines broad conditions which a zoo must meet in order to obtain and retain its licence. Under Section 1A, zoos must be:

“(c) accommodating their animals under conditions which aim to satisfy the biological and conservation requirements of the species to which they belong, including—

(i) providing each animal with an environment well adapted to meet the physical, psychological and social needs of the species to which it belongs; and

(ii) providing a high standard of animal husbandry with a developed programme of preventative and curative veterinary care and nutrition.”

Further guidance on the standards which zoos should meet in order to fulfil their licensing conditions are provided within the Secretary of State’s Standards of Modern Zoo Practice (SSSMZP).

Licensed zoos are inspected on a formal basis every three years, at the beginning, halfway point and end of their six-year licence period. Informal inspections by an officer from the relevant local licensing authority are conducted in intermediate years to check on ongoing compliance with any licensing conditions attached to the zoo’s licence following formal inspections.

Secretary of State’s Standards of Modern Zoo Practice

The requirements within Section 1A (c) of the Zoo Licensing Act are broadened within Sections 1 – 5 of the SSSMZP, which provide general guidance on the provision of food and water, suitable environment, animal health care, behaviour and protection from fear and distress.

The content of the SSSMZP is written on the premise that it is possible to keep any wild animal in captivity and does not make reference to situations where it is not possible to meet the needs of an individual wild animal. Rather, Section 4.3 simply states, “Accommodation must take account of the natural habitat of the species and seek to meet the physiological and psychological needs of the animal.” Based on the content of this report, it can be argued that it is simply not possible for any zoo to meet Section 4.3 of the SSSMZP, or Section 1A (c) of the Zoo Licensing Act, for big cats.

The only specific reference to big cats within the standards is in relation to their hazardous animal categorisation, with all big cat species being categorised as Category 1 (greater risk). Their classification as “greater risk” requires a zoo that keeps big cats to have firearms and persons suitably trained in their use on site, stand-off barriers installed at the enclosure(s) to prevent direct contact between the public and big cats, and for zoos to undertake two animal escape drills per year which involve a Category 1 animal. These requirements are primarily designed to protect the visiting public.

Despite this, the legal status of the SSSMZP remains unclear. Compliance with the standards is not explicitly identified as a licensing requirement within the Zoo Licensing Act. Until a condition is attached to a zoo’s licence, it cannot be directly enforced by the local licensing authority and can often result in welfare issues being allowed to go unresolved for unacceptably long periods of time (Tyson, 2021).

ANIMAL WELFARE ACT 2006

The Animal Welfare Act is the main statute responsible for the protection of animal welfare in England and Wales (The Animal Health and Welfare (Scotland) Act 2006 provides similar protection in Scotland and hereon both pieces of legislation are referred to collectively as the AWA). The AWA covers animals kept as pets (both domestic and wild), farm animals, and animals kept in zoos. The SSSMZP are identified as providing “practical guidance in respect of provisions made by or under the Animal Welfare Act” (Defra, 2012).

However, the SSSMZP were devised and implemented under Section 9 of the Zoo Licensing Act, rather than Section 14 of the AWA. It could therefore be argued that zoos which fail to meet welfare provisions could be prosecuted under both the Zoo Licensing Act and the AWA. Despite welfare issues being commonly raised during zoo inspections, as reflected across wider Europe, very few prosecutions are ever brought against zoos under the Zoo Licensing Act and even less under the AWA (Tyson, 2021). In reality, there appear to be clear conflicts between the AWA and the Zoo Licensing Act, particularly in the continued permitting of the live feeding of vertebrate prey.

CONCLUSION BIG CATS DO NOT BELONG IN ZOOS

The information and evidence summarised in this report highlights that big cats suffer in zoos and that their keeping serves no clear conservation purpose. Evidence of stereotypic behaviour – a sign of significant mental distress – is rife.

Importantly, inbreeding, hybridisation, and genetic bottlenecks have been confirmed by science and known by the zoo industry for decades, yet zoos continue to breed animals for display knowing that they serve little or no purpose as an ‘insurance population.’ Like other animals in zoos, big cats are rarely released into the wild as part of genuine conservation reintroductions; they are simply forced to breed, generation after generation, for paying visitors to observe in captivity in order to generate profits. While some progress has been made towards phasing out white colour morphs from zoos, the breeding and keeping of big cats by European zoos continues unabated.

Zoo licensing authorities across Europe must introduce tougher, mandatory measures relating to enclosure size and design which prioritise animal welfare over visitor experience. Zoos should not be permitted to allow visitors to have contact with big cats, directly or indirectly via ‘experiences,’ nor should zoos be allowed to house prey species near big cats. Authorities and the zoo industry must act to stop the continuous breeding of big cats which further perpetuates the issues highlighted in this report.

Big cats in zoos experience a poor quality of life. The zoo environment cannot meet their fundamental needs. In addition, there is no clear conservation benefit to holding these majestic animals captive. We call on the zoo community to bring an end to big cat suffering and take steps to phase them out of zoo collections. We also call on the public to stop supporting the zoo industry by avoiding these venues to decrease the demand that fuels the desire to hold these awe-inspiring animals captive.

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