The 2008 law that requires the use of an electronic chip to be inserted into pet cats and dogs has has a marked effect on the number of strays and abandoned animals, according to the Portuguese League of Animal Rights (LPDA).
The president of the association, Maria do Céu Sampaio, says that this "does not mean that everything is OK, but this decrease has been significant" and that "the legislation is much better as people who abandon and mistreat animals are punished."
The leader of the Portuguese League adds that spaying and neutering pets are actions that would further contribute to the decline in the number of abandoned animals and says, "the Municipal Councils, rather than invest in rounding up and slaughtering strays, should invest in the sterilisation of all these animals."
Maria do Céu Sampaio believes that "if all councils comply with the sterilisation-identification rule, in a few years the number of abandoned animals will decrease further."
The law requiring the electronic identification of all animals came into force in July, 2008 after which dogs and cats must be identified and registered between three and six months old.
In June 2016, a bill was approved that could see the end municipal vets killing tens of thousands of cats and dogs each year.
Local mayors say the law will increase overcrowding and kennels will need additional funding for food and medical supplies.
The new law states that council vets will have to sterilise animals in their care before trying to find suitable new owners. Cats can be released onto the streets after sterilisation if the kennels are overcrowded.
The People Animals Nature party claims that 100,000 cats and dogs currently are killed by council vets each year.