Spain’s animal protection law, Law 7/2023, has changed how towns and cities must manage the cats that live in parks, streets and gardens. Instead of removing them or putting them down, councils must now manage colonies humanely and keep them in their territories while controlling their numbers.
Capture, sterilise, return
The law establishes the CER method — the Spanish acronym for capture, sterilise and return, known in English as trap-neuter-return — as the main tool for managing cat colonies:
- Capture: cats are caught using safe traps.
- Sterilise: a vet neuters each cat.
- Return: once recovered, the cat is released in the same place.
Because sterilised cats cannot breed, colonies gradually stabilise and shrink. Sterilisation also reduces fighting, spraying and the spread of disease, making it easier for cats and neighbours to live side by side.
What councils must do
- Map colonies: identify and record the cat colonies in their area.
- Draw up action plans: organise regular sterilisation campaigns and veterinary checks.
- Work with vets and volunteers: many colonies are already looked after by registered carers.
- Monitor: keep track of the colonies’ health and numbers.
Funding from the central government is available to help councils set up these programmes, and some towns have already carried out censuses and mapping with the help of volunteers.
Wildlife concerns
Some scientists and conservationists have criticised the approach. Free-roaming cats hunt birds, reptiles and small mammals, which can threaten vulnerable species — a particular concern on islands such as the Balearics, which have endemic species found nowhere else. There are also concerns about the transmission of disease.
The law allows exceptions: where a colony is in a protected natural area, or where there is a verified health risk, authorities can take other measures.
The case for CER
Supporters argue that a managed, sterilised colony causes far less harm than an uncontrolled one, and that removing cats rarely works because new cats move into the empty territory. Over time, they say, sterilisation reduces both the number of cats and their impact.
What residents can do
If you know of a cat colony that is not being managed, contact your town council. And if you have a cat yourself, sterilising it and keeping it identified with a microchip are the most effective ways to prevent more cats ending up on the street.
