Introduction
The care and management of animals with disabilities has grown in the past decade, following advances in veterinary medicine and broader shifts in ethical practices. For example, innovations in measuring pain in animals (Sadler et al. Reference Sadler, Mogil and Stucky2022), advancements in diagnostic and treatment approaches (Queiroga Reference Queiroga2025), and increased focus on welfare-centred practices (De Paula Vieira & Anthony Reference De Paula Vieira and Anthony2020) have contributed meaningfully to the care and management of animals with disabilities. Historically, animals with disabilities may have been recommended for euthanasia (Taylor Reference Taylor2020; Arathoon & Van Patter Reference Arathoon and Van Patter2024), however, it is now more common for animals with disabilities to be kept as companion animals (Birke & Gruen Reference Birke and Gruen2022), managed in zoological organisations (Whitley et al. Reference Whitley, Burnet, Sherwood, Dulaney, Jones, Cordova and Stier2025), and utilised as ambassador animals for educational programming (Caudell & Riddleberger Reference Caudell and Riddleberger2001; Luhrmann Reference Luhrmann2017). In the past decade, there has also been an increase in representation of animals with disabilities in social and mainstream media, children’s entertainment, and marketing (for examples, see Taylor Reference Taylor2020; Weber Reference Weber2024). Despite growth in visibility, animals with disabilities are all too frequently ‘othered’ and seen as separate from their non-disabled counterparts (Murdick et al. Reference Murdick, Shore, Gartin and Chittooran2004; Taylor Reference Taylor2011; Carr Reference Carr2022). Research has demonstrated that the public are quick to notice and comment on animals with visible physical disabilities, with many initial reactions leaning negatively or posing concerns about the animal’s well-being (for examples in a zoological setting, see Whitley et al. Reference Whitley, Burnet, Sherwood, Dulaney, Jones, Cordova and Stier2025). The discrimination against individuals with disabilities in favour of the non-disabled is known as ableism (Friedman & Owen Reference Friedman and Owen2017), which has demonstrable negative impacts on humans with disabilities (Schweik Reference Schweik2009; Sitruk et al. Reference Sitruk, Summers and Lloyd2023; Arathoon Reference Arathoon2024).
While we cannot know the full extent to which animals may perceive differences in cognitive, sensory, or physical abilities, it has been documented that animals adjust their behaviours to accommodate their conspecifics with disabilities, suggesting an awareness of disability in at least some species (Taylor Reference Taylor2020). For example, animals have been observed adjusting their movement speed and provisioning food for conspecifics with disabilities (Taylor Reference Taylor2020). Animals with disabilities in human care may be unable to fully engage in species-appropriate behaviours if enclosures, enrichments, and husbandry practices are not designed with inclusivity in mind (e.g. following universal design principles; Story Reference Story and Smith2001). Universal design, while typically applied to human-centred spaces, can also be applied to animal-centred spaces to ensure that they are usable for all individuals regardless of dis/ability. If animal enclosures, enrichments, and husbandry are not designed, or minimally, modified, to support the needs and capabilities of animals with disabilities, they could contribute to compromised welfare (Carr Reference Carr2022). For example, animals with disabilities may be at risk of reduced welfare if they experience difficulties with movement, obtaining food, manipulating objects in their environments, engaging with conspecifics, or otherwise participating in species-appropriate behaviours.
Despite this, the impact of disability on animal behaviour, and subsequently welfare, is rarely studied (with the exception of primates, reviewed in Stewart et al. Reference Stewart, Joyce, Creeggan, Eccles, Gerwing and Turner2025) or is derived from a single individual’s experience. For example, Ang et al. (Reference Ang, Shender and Ross2017) examined the behaviour and space use of a zoo‐housed chimpanzee (Pan troglodytes) in response to a limb amputation and, similarly, Sayer et al. (Reference Sayer, Whitham and Margulis2007) assessed the posture, locomotion, and manipulation behaviour of a zoo-housed gibbon (Nomascus leucogenys) with one arm. While valuable, these studies are limited in scope and applicability to other taxa and other forms of disability. The few studies that have examined the impact of disability for multiple individuals suggest that individuals with disabilities may have different activity budgets, space use, and/or enrichment engagement compared to their non-disabled conspecifics. For example, Pereira et al. (Reference Pereira, de Azevedo, Colbachini, Cipreste, Pizzutto, Reisfeld and Pizzutto2024) found that bearded dragons (Pogona vitticeps) with limb amputations were more likely to engage with enrichment in a stationary position compared to individuals with all limbs intact. Whereas Dallaire et al. (Reference Dallaire, Field and Mason2012) and Lewis et al. (Reference Lewis, Descovich and Jones2017) examined Asiatic black bears (Ursus thibetanus) and Malayan sun bears (Helarctos malayanus), respectively, and both found that bears with disabilities had different activity budgets and space use compared to non-disabled conspecifics. Specifically, bears with disabilities were less active and used their enclosures less evenly (Dallaire et al. Reference Dallaire, Field and Mason2012; Lewis et al. Reference Lewis, Descovich and Jones2017). Collectively, these studies highlight how animals with disabilities may benefit from modified enclosures, enrichments, and husbandry practices that support their unique needs and capabilities (Carr Reference Carr2022).
Notably, the care and management of disabilities is likely not provided equivalently across animal species. Reviews of publication rates for different taxonomic groups within the fields of animal behaviour and animal welfare science have revealed significant taxonomic biases, with the majority of research focusing primarily on mammals and birds (Rosenthal et al. Reference Rosenthal, Gertler, Hamilton, Prasad and Andrade2017; Binding et al. Reference Binding, Farmer, Krusin and Cronin2020). This taxonomic bias in animal behaviour and animal welfare research impacts the ability to provide evidence-based care for less-studied taxonomic groups, such as reptiles, amphibians, fish, and invertebrates. Additionally, taxonomic biases have been demonstrated in animal welfare assessments, as they are often designed inadvertently with mammals in mind and, as such, the welfare of mammals is often rated higher than all other taxa (O’Brien & Cronin Reference O’Brien and Cronin2023). When welfare assessments are mammal-centric, raters may be uncertain about how to assess welfare for non-mammalian taxa (O’Brien & Cronin Reference O’Brien and Cronin2023). Similarly, one study found that the public’s perception of animals’ cognitive capabilities and capacity to suffer followed phylogenetic scale, with mammals scoring higher than other taxa (Crisante et al. Reference Crisante, Burman and Wilkinson2024). With such pervasive taxonomic biases (Christie Reference Christie2025), it is possible that invertebrates and non-mammalian vertebrates may receive less effective care for a disability, compared to their mammalian counterparts. Further, it has been demonstrated with farm animals (Kılıç & Bozkurt Reference Kılıç and Bozkurt2013), companion animals (McMahon & Wigham Reference McMahon and Wigham2020), and animals in zoos (Ogle & DeSmet Reference Ogle and DeSmet2023), that human perceptions of animals impact the care they provide. Therefore, it is plausible that human perceptions of disability — in addition to potential taxonomic biases — affect the care provided to animals with disabilities, which could impact animal welfare.
Critical anthropomorphism (Burghardt Reference Burghardt1991) provides a useful framework for evaluating the experiences of animals with disabilities (Whitley et al. Reference Whitley, Burnet, Sherwood, Dulaney, Jones, Cordova and Stier2025). Humans are likely to rely on their knowledge or experience of disability in humans to inform their understanding of animal disability (i.e. anthropomorphism: Epley et al. Reference Epley, Waytz and Cacioppo2007; Jenkins et al. Reference Jenkins, Montford and Taylor2020). However, critical anthropomorphism challenges us to critically examine these interpretations, incorporate scientific knowledge of a species’ natural history and behaviour, and consider how variations in form and function may impact an animal’s experience and welfare. Within this framework, it is important to acknowledge that disability impacts humans and animals differently (Jenkins et al. Reference Jenkins, Montford and Taylor2020). Notably, what we as humans may consider a disability may not be disabling — in the same way or to the same extent — for an animal.
Zoological organisations provide an ideal opportunity to study animals with disabilities, as animals of many different species are managed in human care and there are likely numerous individual animals with disabilities across taxonomic groups. However, the prevalence of animals with disabilities in accredited zoological organisations has not been quantified, and little is known about how these animals are managed, whether practices differ across taxa, nor how animal care staff perceive the welfare of animals with disabilities compared to their non-disabled conspecifics. Addressing these gaps will provide a foundation for future research to examine the behavioural adaptations of animals with disabilities. Further, by assessing the ways in which animals with disabilities interact with their environments, we may gain valuable information about how to improve accessibility for all animals in human care, thus enhancing animal welfare broadly.
The goal of this research is to address this knowledge gap by gathering information on: (1) the prevalence and taxa of animals with disabilities in organisations accredited by the Association of Zoos and Aquariums (hereafter AZA); (2) animal care staff perceptions about the welfare of animals with disabilities; and (3) care and management modifications provided to animals with disabilities to promote species-appropriate behaviour. These data will inform future research on animal disability as well as strategies to enhance animal welfare, both for animals with disabilities as well as their non-disabled counterparts.
Materials and methods
A two-part survey was created using Alchemer online survey software (alchemer.com). Part 1 (Supplementary material 1) was intended to be completed by one member from an AZA-accredited organisation who was knowledgeable about the prevalence of animals with disabilities within their organisation as a whole (e.g. veterinarian, curator). Part 2 (Supplementary material 2) was a more in-depth survey intended to be completed by any interested animal care staff from an AZA-accredited organisation who works with at least one animal with a disability to gather information about their perceptions regarding the welfare of animals with disabilities and if/how they provide modifications to animals with disabilities to support species-appropriate behaviour. For the purposes of this research, we defined an animal with a disability as any animal (vertebrate or invertebrate) that has lost a critical adaptation (e.g. one of their senses, part or full appendage) that impacts the animal’s stability, mobility, typical behaviour, or perception of their environment. Based on this definition, a disability could be physical, cognitive, and/or sensory and may be singular or multifaceted (i.e. multiple disabilities may co-occur within a single animal).
Survey responses were solicited via posts to AZA network community pages (network.aza.org/communities; an online network accessible to staff with active AZA memberships from AZA-accredited organisations). Additionally, staff from Lincoln Park Zoo shared the survey with colleagues at other AZA-accredited organisations. Surveys were open for participation from 29 April–31 July 2025 (approximately 3 months); the survey was re-posted monthly to encourage participation. The study PI (SLO) did not reach out to organisations directly in order to keep survey participation anonymous. Prior to sharing data with the study PI, organisation names were pseudonymised by a zoo staff member not associated with the research project; this allowed the study PI to group surveys from a single organisation while keeping survey data anonymous. For organisations that submitted duplicate Part 1 surveys (n = 3), the most recently submitted survey was retained for the final data-set, and the previously submitted survey was excluded. All surveys from Part 2 were retained in the final data-set.
Organisational data
For organisations that submitted multiple surveys (i.e. Part 1 and Part 2, or multiple Part 2 surveys), organisational data (e.g. organisation type and size) were checked for consistency. When discrepancies were found (i.e. surveys from the same organisation did not have the same information listed for organisation type and size), then the organisational information provided in Part 1 was retained for analysis. If an organisation did not submit a Part 1 survey, but had multiple Part 2 surveys, then the majority response was retained for analysis.
Survey data
As individual respondents within organisations may have had different interpretations of what constituted an animal with a disability, data on animals with disabilities were counted as the percentage of survey respondents who indicated they had an animal with a disability in their care, as opposed to the percentage of organisations that reported animals with disabilities in their care.
Similarly, all data from the surveys are presented as the percentage of the total number of respondents that answered a given question. Sample sizes are included for each survey response reported.
Within the survey, taxonomic categories were as follows: mammals, birds, reptiles, amphibians, fish, insect, arachnid, mollusc, and other invertebrates (i.e. not an insect, arachnid, or mollusc). Results are presented following these categories.
To assess care staff perceptions of animals with disabilities, respondents were asked to rate whether they perceived the welfare of the animals with disabilities in their care as average relative to non-disabled conspecifics (i.e. similar welfare), better than average, or worse than average. To assess potential taxonomic biases in care staff perceptions, this question was asked separately for each taxonomic group.
Data analysis
Summary statistics were procured via Microsoft Excel®. Statistical analyses were performed in R 4.5.0 (R Core Team 2025). A Kolmogorov-Smirnov test was used to determine whether the prevalence of disability across taxonomic groups had a different distribution than expected based on the estimated number of individuals of each taxonomic group within the AZA population. Data on the estimated AZA population were gathered via the Zoological Information Management System (ZIMS Species Holdings 2025), which categorises vertebrate groups separately (i.e. mammals, birds, reptiles, amphibians, fish), and invertebrates collectively.
Ethical note
Survey participation was voluntary and respondents could end participation at any time. Further, no personally identifying information was collected from survey respondents. This research was deemed exempt by the Lincoln Park Zoo Institutional Review Board (IRB).
Results
There were 34 survey respondents for Part 1 and 81 respondents for Part 2, representing a total of 45 organisations (approximately 19% of 243 accredited AZA organisations as of October 2025). Zoos accounted for the majority of organisations (68%; n = 78), followed by zoo/aquariums (18%; n = 21), other (8%; n = 9), and aquariums (6%; n = 7; Figure 1). Organisations that selected ‘other’ as their organisation type described themselves as: nature centre, bird park, museum, zoo/rehabilitation, and aquarium/rescue. The majority of organisations had between 50–149 full-time staff (41%; n = 47 organisations), followed by 150–249 full-time staff (30%; n = 34), under 50 full-time staff (23%; n = 27), and over 250 full-time staff (6%; n = 7; Figure 1). Data on organisation types and sizes provide context for survey responses, as zoos and aquariums often specialise in different types of taxa (e.g. zoos often have more mammals and birds whereas aquariums often have more fish and invertebrates). All but one organisation (44 out of 45 organisations surveyed) reported at least one animal with a disability in their care.
Type and size of organisations (n = 115 respondents from 45 organisations) participating in the research survey on animals with disabilities in zoological organisations.
Figure 1. Long description
The y-axis is labeled Number of respondents and ranges from 0 to 100 in increments of 20. The x-axis lists four categories: Zoo, Zoo and Aquarium, Other, and Aquarium. A legend on the right identifies four staff size categories: less than 50 full-time staff (yellow), 50-149 full-time staff (orange), 150-249 full-time staff (magenta), and 250 plus full-time staff (blue).
* Zoo: The largest bar reaching approximately 78 total respondents. It consists of roughly 18 in the less than 50 category, 36 in the 50-149 category, 20 in the 150-249 category, and 4 in the 250 plus category.
* Zoo and Aquarium: Reaches approximately 21 total respondents. It consists of roughly 2 in the less than 50 category, 5 in the 50-149 category, 11 in the 150-249 category, and 3 in the 250 plus category.
* Other: Reaches approximately 9 total respondents. It consists of roughly 6 in the less than 50 category and 3 in the 50-149 category.
* Aquarium: Reaches approximately 7 total respondents. It consists of roughly 2 in the less than 50 category, 2 in the 50-149 category, and 3 in the 150-249 category.
Taxonomic representation of animals with disabilities
Mammals (66%; n = 76 respondents) and birds (61%; n = 70) accounted for the majority of reports of animals with disabilities, followed by reptiles (35%; n = 40), amphibians (10%; n = 11), fish (10%; n = 12), insects (5%; n = 6), other invertebrates (i.e. non-insect, arachnid, or mollusc) (5%; n = 6), and arachnids (2%; n = 2). There were no reports of molluscs with disabilities. The taxonomic distribution of animals with disabilities reported in this study does not follow the taxonomic distribution of the AZA population (two sample Kolmogorov-Smirnov test: D[6,6] = 1; P = 0.002), as reported in the Zoological Information Management System (ZIMS Species Holdings 2025). Notably, not all AZA organizations are ZIMS users, and thus the data included are estimates of prevalence. The prevalence of disability is more common in mammals, birds, and reptiles than would be expected based on the number of individuals in the AZA population (Figure 2). Conversely, disability is less common in fish and invertebrates than would be expected based on the number of individuals in the population (Figure 2). Due to limitations in observing individual animals in large schools of fish or colonies of invertebrates, it is possible that disability may be less frequently reported for these taxa.
Estimated taxonomic distribution in organisations accredited by the Association of Zoos and Aquariums (AZA) compared to the taxonomic distribution of animals with disabilities as reported in the research survey on animals with disabilities in zoological organisations.
Figure 2 Long description
The graph y-axis is labeled by taxonomic group (from left to right): mammal, bird, reptile, amphibian, fish, and invertebrate. The percentages of animals with disabilities as reported in the survey are 34% mammals, 31% birds, 18% reptiles, 5% amphibians, 5% fish, and 6% invertebrates. The estimated percentages of these taxonomic groups within the Assoxiation of Zoos and Aquariums (AZA) population are 6% mammals, 7% birds, 4% reptiles, 6% amphibians, 32% fish, and 46% invertebrates.
While the survey did not explicitly ask respondents to provide information regarding the specifics of an animal’s disability, some details were voluntarily provided via write-in responses. From these data, some types of disabilities mentioned included: amputations, permanent flight restriction, blindness/visual impairment, arthritis, mobility impairments, foot deformities, and deafness (Supplementary material 3). Notably, cognitive disabilities were not mentioned.
Perceptions of welfare for animals with disabilities
Across all taxa, the majority of respondents rated the welfare of animals with disabilities as average compared to their non-disabled counterparts (78%; n = 93 respondents). Meanwhile 17% (n = 20) rated the welfare of animals with disabilities as better and 5% (n = 6) rated the welfare of animals with disabilities as worse than that of their non-disabled counterparts. Figure 3 shows the welfare perception ratings for each taxonomic group.
Survey respondents’ perceptions of welfare for the animals with disabilities in their care relative to the non-disabled animals in their care of the same taxa (n = 119 responses), as reported in the research survey on animals with disabilities in zoological organisations.
Figure 3 Long description
The graph y-axis is labeled by taxonomic group (from left to right): mammal, bird, reptile, amphibian, fish, arachnid, insect, and other invertebrate. Most survey respondents answered that they perceived the welfare of animals with disabilities in their care as average or similar to animals without disabilities. Values (count of survey respondents) per taxonomic group are: mammal: 30, bird: 33, reptile: 11, amphibian: 5, fish: 6, arachnid: 2, insect: 3, and other invertebrate: 3. A few survey respondents answered that they perceived the welfare of animals with disabilities in their care as better than average. Values (count of survey respondents) per taxonomic group are: mammal: 10, bird: 5, reptile: 4, and fish: 1. A few survey respondents answered that they perceived the welfare of animals with disabilities in their care as worse than average. Values (count of survey respondents) per taxonomic group are: mammal: 1, bird: 1, reptile: 1, amphibian: 2, and other invertebrate: 1.
Enclosure modifications (26%; n = 49 respondents), husbandry modifications (24%; n = 45), and veterinary care (22%; n = 40) were denoted as the highest contributing factors to perceived positive welfare of animals with disabilities. These were followed by enrichment modifications (19%; n = 35), other reasons not listed (5%; n = 10), and the use of prosthetics/orthotics (4%; n = 7).
Conversely, the highest contributing factors to perceived negative welfare of animals with disabilities were lack of enclosure modifications (30%; n = 11 respondents), other reasons not listed (30%; n = 11), and lack of enrichment modifications (24%; n = 9). Lack of husbandry modifications and lack of prosthetics/orthotics were rated the same (8% each; n = 3 each). Notably, no respondents listed a lack of veterinary care as a reason for the perceived negative welfare of animals with disabilities.
Modifications to enclosures, enrichments, and husbandry practices
Enclosure modifications were most frequently reported for birds (42%; n = 58 respondents), mammals (37%; n = 52), and reptiles (17%; n = 23) with disabilities. Only 4% (n = 6) of respondents reported provision of enclosure modifications for amphibians, fish, and insects, combined. There were no reports of enclosure modifications provided to arachnids or other invertebrates (i.e. non-insect, arachnid, or mollusc).
Enrichment modifications followed the same pattern, with most modifications provided to birds (39%; n = 47 respondents), mammals (36%; n = 43), and reptiles (18%; n = 21) with disabilities. Only 7% (n = 9) of respondents reported provision of enrichment modifications for amphibians, fish, and insects, combined. There were no reports of enclosure modifications provided to arachnids or other invertebrates (i.e. non-insect, arachnid, or mollusc).
Similarly, husbandry modifications were primarily provided to birds (37%; n = 46 respondents), mammals (35%; n = 44), and reptiles (19%; n = 24) with disabilities. Only 3% (n = 4) of respondents reported providing husbandry modifications to amphibians and 2% of respondents each reported providing husbandry modifications to fish, insects, and other invertebrates (i.e. non-insect, arachnid, or mollusc) (n = 2 respondents per taxa). There were no reports of husbandry modifications provided to arachnids. Figure 4 shows the types of modifications provided for each taxonomic group and Table 1 provides summarised examples of modifications provided by survey respondents for the animals with disabilities in their care. For all written responses organised by modification type and taxa, see Supplementary material 3.
Types of modifications (n = 381 modifications) provided to animals with disabilities based on the research survey of animals with disabilities in zoological organisations.
Figure 4. Long description
The Y axis is labeled Number of respondents and ranges from 0 to 160 in increments of 40. The X axis lists eight animal categories. A legend to the right identifies three modification types: Enclosure modification (yellow, bottom), Enrichment modification (magenta, middle), and Husbandry modification (blue, top).
* Bird: The highest total, reaching approximately 150. It consists of roughly 60 enclosure, 45 enrichment, and 45 husbandry modifications.
* Mammal: The second highest, reaching approximately 140. It consists of roughly 50 enclosure, 45 enrichment, and 45 husbandry modifications.
* Reptile: Reaches approximately 70. It consists of roughly 25 enclosure, 20 enrichment, and 25 husbandry modifications.
* Amphibian: Reaches approximately 10, with small segments for all three types.
* Fish: Reaches approximately 8, primarily husbandry and enrichment.
* Insect: Reaches approximately 5, primarily enclosure and husbandry.
* Other Invertebrate: Reaches approximately 2, consisting only of husbandry modification.
* Arachnid: Shows a value of zero or near-zero.
Examples of enclosure, enrichment, and husbandry modifications provided by respondents for animals with disabilities in their care based on the research survey of animals with disabilities in zoological organisations. For a full list of write-in responses organised by modification type and taxa, see Supplementary Material 3
Table 1. Long description
The table consists of two columns titled Modification type and Examples.
Row 1, Enclosure: Examples include ramps, steps, or ladder perching for accessing higher areas; grip mats on sloping areas; reduced incline of sloping areas; platforms and perching within lower areas; and soft padding or substrate in areas where an animal could potentially fall.
Row 2, Enrichment: Examples include use of sensory enrichment based on the animal's ability, such as scent or tactile instead of visual for blind animals; auditory cues to assist with enrichment location; and changing enrichment locations to more easily accessible areas.
Row 3, Husbandry: Examples include schedule changes for medication delivery; training for physical therapy or medical needs; manual care for animals requiring assistance with self-maintenance; and auditory cues to alert blind animals before servicing.
For instances when modifications were not provided to an animal with a disability, respondents reported this was primarily due to limited resources (36%; n = 8) and limited staff time (23%; n = 5). Limited knowledge about modifications was reported by 18% (n = 4) of respondents. Similarly, 18% of respondents (n = 4) reported that providing modifications was not an organisation priority. Only one respondent reported that limited staffing was the reason modifications were not provided.
Respondents reported that information about how to provide animals with modifications was gathered primarily from discussions with animal care staff (21%; n = 60), discussions with veterinary staff (20%; n = 57), and discussions with other organisations (14%; n = 39). Following this, 11% of respondents (n = 31) gathered information about modifications via discussions with behavioural husbandry staff, 11% (n = 32) gathered information via internet searches, and 11% (n = 30) gathered information from scientific literature. Only 7% (n = 22) of respondents indicated they gathered information about modifications from the Association of Zoos and Aquariums or other accrediting bodies. Six respondents (2%) reported other sources of information including discussions with maintenance staff, social media, discussions with physical therapists specialising in animal care, and social forums for zookeepers. Three respondents (1%) indicated they had not gathered any information about how to provide modifications for animals with disabilities. Notably, resources about how to provide modifications for animals with disabilities are limited and differences in the availability of resources and/or connections to other organisations within AZA may impact the ability of individual organisations to provide impactful modifications that enhance welfare.
Prosthetics and orthotics
Reports of prosthetic and orthotic use were relatively low. There were 7 reports of prosthetic use: 3 reports for birds, 2 for reptiles, and 2 for other invertebrates (i.e. non-insect, arachnid or mollusc). There were 10 reports of orthotic use: 8 for birds and 2 for mammals.
Discussion
Zoos and aquariums accredited by the Association of Zoos and Aquariums (AZA) provide care and modifications for animals with disabilities; however, modifications to enhance welfare are predominantly directed toward birds and mammals, potentially reflecting uneven knowledge about different taxonomic groups as well as differences in organisational capacity to support animals with disabilities. All but one of the organisations surveyed reported animals with disabilities in their care. A range of organisation sizes participated, including both zoos and aquariums, representing approximately 19% of AZA-accredited organizations. The survey response rate of this study is less than other recently published surveys of members from accredited zoological organisations (e.g. Gray et al. Reference Gray, Faust, Kuykendall, Bladow, Schad Eebes and Che‐Castaldo2022; Brando et al. Reference Brando, Rachinas-Lopes, Goulart and Hart2023); however, the range of organisation sizes and types that participated in the survey suggest that animals with disabilities may be common within AZA-accredited organisations. This highlights the pressing need to assess the effectiveness of modifications provided to animals with disabilities, evaluate care practices across taxonomic groups, and adopt strategies that enhance welfare of animals with disabilities along with their non-disabled counterparts.
We, as humans, are limited in our understanding of what could constitute a disability in non-human animals, who have incredibly diverse sensory capacities (Taylor Reference Taylor2020). Thus, it is notable that the types of disabilities reported by survey respondents were those that mirror the types of disabilities that occur in humans. Similarly, disabilities reported in animals were those that were outwardly visible (i.e. physical) or conditions associated with demonstrable changes in the animal’s behaviour (e.g. deafness as demonstrated by no longer responding behaviourally to auditory cues).
Research on animal behaviour has historically been conducted from an ableist lens (Friedman & Owen Reference Friedman and Owen2017), in which variations in form or ability are assumed to be detrimental from a fitness perspective. However, the field is beginning to incorporate perspectives from critical disability studies (e.g. Taylor Reference Taylor2017; Goodley Reference Goodley2024) in their interpretations of animal behaviour (e.g. Escalante & Elias Reference Escalante and Elias2022). As Escalante and Elias (Reference Escalante and Elias2022) argue, from an evolutionary perspective, animals are likely to develop robustness and flexibility in traits that will increase their likelihood of survival. Notably, disability, as traditionally defined in human populations, includes both the impairment and the interaction with environmental factors (WHO 2023). The impairment on its own is not necessarily disabling unless the individual is limited by interactions between their impairment and their environment. This is especially relevant when considering animals in human care, whose environments are inherently limited to what is provided by humans. As such, if animals are not provided with accessible enclosures, enrichments, and care that support species-appropriate behaviour, then we may unintentionally contribute to an animal’s disability in ways that could negatively impact their welfare. For example, enclosures with steep slopes or slippery surfaces may be disabling for an animal with limited mobility, visually oriented enrichment may be disabling for an animal with vision loss, and training with auditory cues may be disabling for an animal with deafness. In wild populations where individuals theoretically have fewer environmental constraints and presumably greater ability to compensate, loss of a critical adaptation — as disability was defined in this study — and the subsequent changes in behaviour that may occur could simply be interpreted as variation along the spectrum of species-appropriate behaviour as opposed to a disability. Although it is critical to note that variation in species-appropriate behaviour, and the degree to which variation in form and function either is or is not disabling, will depend on the environment in which the animal lives and the individual’s robustness and ability to compensate.
Both disabled vertebrates and invertebrates were reported in the survey, albeit unequally, as there were few reports of invertebrates with disabilities. There was a noticeable lack of modifications for most taxa outside of birds, mammals, and reptiles. Interestingly, birds were the second most reported taxonomic group with disabilities and yet had the highest reports of modification provision. Modifications were rarely provided to amphibians, fish, and insects, and there was not a single report of modifications of any type (enclosure, enrichment, or husbandry) provided to an arachnid, despite these taxonomic groups being common in AZA organisations. Notably, some respondents reported removing enclosure or enrichment components for animals with disabilities (e.g. removed opportunities for higher perching, removed climbing opportunities, etc; Supplementary material 3). While this may sometimes be required for safety reasons, it is important that equivalent opportunities for animals to express species-appropriate behaviour are provided. Rather than limit an animal’s opportunities to express species-appropriate behaviours, efforts should be made to make enclosures and enrichments more accessible whenever feasible (e.g. addition and/or modification of ramps, steps, perching, and/or platforms that allow animals to safely access higher areas of their enclosure). The removal of species-appropriate opportunities for individuals with disabilities could negatively impact animal welfare as it reduces an individual’s opportunities for choice and control (Englund & Cronin Reference Englund and Cronin2023). Previous research with bearded dragons found that individuals with amputated limbs engaged with enrichment similarly to their non-disabled conspecifics, using even ‘high challenge’ enrichment at similar rates; these individuals simply engaged with the enrichment differently than their conspecifics without an amputation, often doing so while stationary or lying down (Pereira et al. Reference Pereira, de Azevedo, Colbachini, Cipreste, Pizzutto, Reisfeld and Pizzutto2024). These types of studies inform our expectations of animal behaviour and challenge ableist assumptions that animals with disabilities are unable or uninterested in expressing certain behaviours due to their disability.
Most respondents (78%) perceived the welfare of the animals with disabilities in their care as average compared to non-disabled animals and very few respondents (5%) reported a negative perception of welfare for the animals with disabilities in their care. Some respondents (17%) perceived the welfare of the animals with disabilities in their care as better than average, but this response was only recorded for mammals, birds, and reptiles — who had the highest reports of modifications provided — as well as one response recorded for fish. It is notable that most respondents rated the welfare of the animals with disabilities in their care as average compared to non-disabled conspecifics, despite reported differences in the provision of enclosure, enrichment, and husbandry modifications across taxa. These findings could suggest that care staff do not consider the provision of enclosure, enrichment, and/or husbandry modifications as necessary or influential as regards the welfare of certain taxonomic groups (e.g. taxa that are not birds, mammals or reptiles) — or that current enclosures/enrichment/husbandry are sufficient as they are for these taxa and do not require modifications for an animal with a disability. Notably, there may have been a selection bias in response to this survey question, such that individuals with a negative perception of animals with disabilities may have opted out of responding to this part of the survey.
Study limitations and research opportunities
There are a few limitations to acknowledge with this work. First, this study represented 19% of AZA-accredited organisations as opposed to the full AZA population. While survey respondents included individuals from organisations that vary in type (zoo, aquarium, zoo/aquariums, other) and size (< 50 to 250+ full-time staff) — and thus represent the variety of organisations within AZA — it is important to interpret the results of the study cautiously. Additionally, a probabilistic sampling technique was not used for this study; therefore, it is possible that individuals that care for animals with disabilities self-selected to participate whereas individuals that do not care for animals with disabilities may have opted out of participating in the survey. Consequently, we are unable to conclude whether the prevalence of animals with disabilities documented in this study accounts for all the animals with disabilities within AZA organisations or whether this documented prevalence represents the minimum.
More basic and applied research on historically understudied taxa (i.e. non-mammal and non-bird) can inform evidence-based care practices that enhance welfare whether an animal is disabled or non-disabled. In particular, multi-zoo/multi-aquarium studies provide a robust framework for assessing and identifying best practices across all taxonomic groups. Future research should examine the effectiveness of modifications provided to animals with disabilities as well as investigate why modifications may be more common for birds, mammals, and reptiles than other taxonomic groups. Importantly, research findings should be used to inform future, more accessible enclosure and enrichment design as well as inclusive, evidence-based husbandry practices. Additionally, future research that more thoroughly examines caregiver perceptions of behaviour, welfare, and care requirements for different taxonomic groups will be informative for developing targeted training for animal care staff that supports the welfare of animals with disabilities. Collectively, the continued study of animals with disabilities can inform animal welfare and the field of animal behaviour more broadly. For example, understanding the types of disabilities that animals have, and in turn, how animals cope and behaviourally adapt to accommodate their disability, will undoubtedly grow our understanding of key fields of study within animal behaviour, such as biomechanics, communication, and cognition.
Animal welfare implications
Animals with disabilities present distinct welfare considerations, as physical, sensory, and/or cognitive disabilities are likely to impact how individuals interact with their environments, co-habitants, and the humans that care for them. Mismatches between an animal’s abilities and their environment, enrichment, and/or husbandry could potentially restrict an animal’s access to important resources, reduce opportunities for choice and control, or limit the expression of species-appropriate behaviours; all of which may compromise welfare. In socially housed species, a disability could potentially influence group dynamics and exposure to aggression or exclusion from resources and thus require careful monitoring and management. Mirroring universal design principles for humans (Story Reference Story and Smith2001), focusing on how animals with disabilities use their space and interact with enrichments can inform future accessible design that enhances welfare for all animals, regardless of dis/ability. Additionally, the inclusion of signage for animals with disabilities in zoological organisations can promote empathy for individuals with disabilities (Whitley et al. Reference Whitley, Burnet, Sherwood, Dulaney, Jones, Cordova and Stier2025) and, in turn, may promote positive perceptions of disability for animal care staff in addition to zoo visitors (for guidance on appropriately depicting animals with disabilities, see Whitley et al. Reference Whitley, Dulaney, Wehr, Burnet, Jones and Cordova2026). Collectively, these considerations highlight the importance of adopting inclusive, evidence-based approaches to managing animals with disabilities. In turn, the development and practice of these approaches may broadly impact animal welfare regardless of dis/ability by promoting more individualised and adaptive care practices throughout zoos and aquariums.
Supplementary material
The supplementary material for this article can be found at http://doi.org/10.1017/awf.2026.10104.
Acknowledgements
Thank you to Katherine Cronin, Jason Wark, Maureen Leahy, Kathryn Gamble, Marisa Shender, and Lincoln Park Zoo Research Committee for early feedback on the survey. Thank you to Bill Green, Lanie Crowe, Isabel DePaz, and Alex Kim for thoughtful discussions about animal disability. Thank you to Brian Slattery for assistance with survey creation and management. Thank you to Lincoln Park Zoo Animal Care staff for assistance with survey dissemination. Thank you to Ignacio Escalante for feedback on an early draft of this manuscript. Thank you to Megan Brown for assistance with ZIMS data gathering. Thank you to all organisations and individuals who participated in the survey. Lastly, thank you to two anonymous reviewers who provided valuable feedback on an earlier version of this manuscript.
Competing interests
None.
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