By Bridget Craghill
While snakes are often excluded from mainstream animal welfare discussions, new research is rapidly reshaping scientific and legal understandings of their needs. A new study suggests that housing conditions have significant neurological and behavioural impacts on these animals.
In March 2025, The Journal of Comparative Neurology published a peer-reviewed study demonstrating that environmental enrichment significantly enhances brain development in juvenile western hognose snakes (Heterodon nasicus). Snakes housed in enriched environments developed larger brain regions critical to motor control, sensory processing and behavioural complexity (Nagabaskaran et al., 2025, pp. 4–5). The only variable was environmental: vivaria with naturalistic features versus barren rack drawers, which are standard in commercial and private snake and reptile keeping. A similar study by Cargill et al. (2022) had already established that enriched enclosures correlate with fewer signs of stress and illness in snakes. Thus, this study’s findings add to the growing scientific consensus that captive snakes benefit from naturalistic, enriched housing.
While rack-style drawers commonly used in commercial and private reptile housing are not explicitly prohibited under UK law, under Section 9 of the Animal Welfare Act 2006, animal keepers are legally obligated to take “reasonable steps” to meet an animal’s welfare needs “to the extent required by good practice”. These include the need for a suitable environment and the need to exhibit normal behaviour patterns. Thus, what qualifies as “suitable” is a dynamic standard, shaped by developments in veterinary science, academic research, and professional guidance. As scientific consensus increasingly indicates that deprived environments can hinder neurological development and suppress natural behaviour, prolonged use of such housing without clear justification may, over time, fall below the threshold of reasonable care and what’s considered “good practice”. If such housing results in measurable harm or suffering, it could support neglect claims under the Animal Welfare Act.
UK legislation already mandates environmental enrichment in regulated domains. Under the Animal Welfare (Licensing of Activities Involving Animals) (England) Regulations 2018, licensed operations, such as pet sellers and exhibitors, must minimise stress and provide appropriate environmental conditions (Schedule 2, para. 10; Schedule 3, para. 7). Non-compliance can result in revocation of a licence under Regulation 15. Farmed animal welfare law also imposes enrichment duties. For instance, pigs must be given manipulable materials, and poultry must be provided litter, perches, and pecking objects under the Welfare of Farmed Animals (England) Regulations 2007. In zoos, the Standards of Modern Zoo Practice (2025) require enrichment and cognitive stimulation even for reptiles, with compliance monitored under the Zoo Licensing Act 1981. This highlights a discrepancy in regulation, where enrichment is compulsory in professional contexts such as agriculture, zoos, and commercial breeding, but not for reptiles kept privately. These private, non-commercial keepers remain subject only to the general welfare duty under the Animal Welfare Act 2006.
Switzerland provides a structured comparative model in reptile welfare law. Under the Swiss Animal Protection Ordinance (TSchV, SR 455.1), keepers must adhere to legal standards for reptiles. These include minimum enclosure sizes, temperature gradients, lighting cycles, humidity levels and environmental enrichment. Switzerland’s standards are legally binding and species-specific, offering a preventive regulatory model. By contrast, UK law imposes a general duty of care but does not prescribe specific environmental parameters for reptile species and other niche exotics. While DEFRA (and its counterparts in the devolved nations) and animal welfare organisations offer guidance, there is no statutory Code of Practice for reptiles, and enforcement remains largely post-incident, relying on evidence of harm or failure to meet broadly defined welfare needs.
While current enforcement relies on evidence of harm or stress rather than housing design alone, the law’s threshold of “reasonable steps” evolves with veterinary and scientific consensus. Courts and animal welfare inspectors in the UK are not bound by fixed statutory definitions when assessing welfare cases. However, regulatory frameworks such as the Defra-issued Farm Animal Welfare Codes of Practice and the Zoo Licensing Act 1981 already mandate environmental enrichment as a legal requirement in institutional settings.
Currently, no publicly reported UK court cases specifically discussing environmental enrichment for reptiles under the Animal Welfare Act 2006. However, enforcement trends and interpretations of Section 9 are increasingly including environmental conditions as integral to animal welfare. Legal precedents such as Barker v RSPCA [2018] EWHC 880 affirm that inadequate environmental conditions, including confinement and deprivation of natural behaviours, can breach the duty of care. Furthermore, the RSPCA and other prosecuting bodies regularly cite barren, understimulating environments as aggravating factors in welfare cases, even where charges primarily focus on unnecessary suffering under Section 4. These enforcement patterns illustrate an increasing legal recognition that species-specific behavioural and ecological needs help define what constitutes a “suitable environment.”
The inconsistency is that rack systems are increasingly discouraged or prohibited in zoos, research laboratories, and licensed animal establishments. Yet the animal’s biology does not change based on context. A snake in a private collection has the exact fundamental cognitive and behavioural needs as one in a zoological setting. Allowing lower standards for the same species based purely on the ownership category leads to a regulatory double standard unmoored from scientific and ethical rationale.
The trajectory of animal law in the UK suggests that neglecting environmental enrichment, especially where credible evidence links its absence to cognitive and emotional harm, may soon become legally indefensible. The combined weight of statutory obligations, scientific authority and evolving judicial interpretation (hopefully) points toward a future where failure to enrich is considered neglect.
About the author Bridget Craghill
I am a Law and Politics LLB student at Queen Mary University of London with a longstanding passion for animal welfare and advocacy. I have been involved in animal rights activism: writing to MPs and participating in protests. My commitment to animal welfare led me to volunteer in a range of animal-related environments, such as veterinary practices, farms and zoos, where I gained insight into practical and ethical challenges of working with animals.