Guest blog by Russell Whiting, Senior Policy and Public Affairs Advisor, Crustacean Compassion

Decapod crustaceans, animals like crabs, lobsters and prawns, may not be the first animals that come to mind when we think about animals used in research. Yet they are not only being routinely used but also being deprived of the protections afforded to all other animals. At Crustacean Compassion, we’ve spent the last few years uncovering the scale of this overlooked issue and making the case for change.

Sentient in law, unprotected in research

Animal Law Day celebrates the progress made in recognising animals in law, but it is also a reminder that legal recognition must be matched by meaningful legal protection. Few examples illustrate that better than decapod crustaceans.

When the UK Government recognised decapod crustaceans as sentient animals in the Animal Welfare (Sentience) Act 2022, it acknowledged what the scientific evidence had been showing for years: these animals are capable of experiencing pain, distress and pleasure.

Yet despite that legal recognition, they remain excluded from the Animals (Scientific Procedures) Act 1986 (ASPA), the legislation that regulates the use of animals in scientific research. They are the only animals recognised as sentient in UK law that fall outside the scope of ASPA.

This omission means that, unlike animals protected by ASPA, crustaceans can be used in scientific experiments without any oversight from the Home Office, research is not subject to the ethical justification and licensing requirements that apply under ASPA, and there are no standards for the housing or care of the animals.

Uncovering the hidden scale of decapod research

One of the consequences of decapods being excluded from ASPA is a lack of transparency.

Because there is no legal requirement to report their use, there are no official statistics showing how many decapod crustaceans are used in UK research each year or the types of procedures they undergo. Without legal reporting requirements, Freedom of Information (FOI) requests are currently the only way to begin understanding the scale of decapod use in UK research. This lack of transparency is not only an animal welfare issue; it also makes it harder for researchers, institutions, and policymakers to make evidence-based decisions about the use and regulation of these sentient animals.

To begin addressing this evidence gap, Crustacean Compassion has spent several years using FOI requests to gather information directly from UK universities. Our data show that nearly 30,000 decapod crustaceans have been used in UK universities between 2018 and 2024. That’s almost 5,000 every year – used in experiments that may involve invasive procedures, deprivation, or even death, all without a single legal safeguard.

While these can only ever provide a partial picture, they have helped us to build the most comprehensive overview yet of decapod crustacean use in UK research. We know the true figure is likely to be much higher because many universities confirmed they used decapods but declined to provide numbers.

Our forthcoming report brings together this evidence, exploring the scale of decapod use in UK universities highlights significant variation in how institutions record, review and oversee research involving these animals.

Beyond the numbers

The figures are only part of the story. Our work has also helped us understand more about how decapods are used in research.

The information we’ve gathered indicates that many animals are collected directly from the wild, particularly by institutions near the coast, while others are obtained from commercial suppliers. Some are returned to the wild after studies, but many die during experiments or are euthanised afterwards.

We have also found significant variation in the ethical oversight applied by universities. While some institutions voluntarily submit decapod research to their Animal Welfare and Ethical Review Bodies (AWERBs), others have little or no formal review because decapods fall outside the scope of ASPA. As a result, the welfare of sentient animals can depend largely on where research takes place rather than on a consistent national standard. It also creates unnecessary variation in research governance. Consistent ethical oversight, reporting and welfare standards don’t just protect animals, they improve transparency, reproducibility and public confidence in scientific research.

Although AWERB review is currently voluntary, we believe it is an important interim safeguard while decapods remain outside ASPA. Our findings highlight the need for more consistent ethical oversight across UK institutions, and we hope they will support researchers, universities and policymakers in developing a more robust framework for decapod research until statutory protections are introduced.

Alongside this work, we continue to provide evidence to government as it considers future regulation of decapod research.

From recognition to protection: include decapod crustaceans in ASPA, ASAP

The case for protecting decapod crustaceans in research has been building for years, and Crustacean Compassion has long campaigned to close the legislative loophole that leaves them outside ASPA.

When the London School of Economics reviewed the scientific evidence that led to decapods being recognised as sentient in the Animal Welfare (Sentience) Act 2022, it also recommended that they should be brought within the scope of ASPA. More recently, the Animal Sentience Committee reached the same conclusion, stating that inconsistencies in the protection of sentient animals are “not only unjustifiable on scientific grounds, they also reflect an important matter of principle.”

A Government Call for Evidence in 2023 was an important first step, but progress then stalled. Following continued engagement from Crustacean Compassion and others, the Government has now indicated that researchers will develop Codes of Practice for decapod research and that the Animals in Science Committee will finally consider future regulation.

These are encouraging developments, but voluntary guidance is no substitute for legal protection. The scientific evidence for decapod crustacean sentience has already been accepted and the legislation framework has mechanisms to extend the definition of protected animals. Cephalopod molluscs were brought within ASPA on the basis of scientific evidence, and that same level of evidence now exists for decapod crustaceans. We are simply asking the Government to follow the same path.

Our forthcoming report will provide the clearest picture yet of decapod crustacean use in UK universities and the regulatory gaps that remain. We hope it will help inform the next stage of discussions and strengthen the case for including decapod crustaceans in ASPA, ASAP.

If you’d like to be among the first to read the report and follow our campaign to #ProtectCrabsInLabs, sign up to the Crustacean Compassion newsletter. Together, we can help ensure that sentient decapod crustaceans receive the protections they deserve.