The presence of dog poop on the streets of Spain is one of the aspects that bothers many people, whether pedestrians who have to try to dodge it or municipal officials who have to spend thousands of euros a year to get rid of it from pavements and parks.

It has been shown that "one of the most effective measures" to prevent the proliferation of poop in the streets is fines. However, most councils consider it a minor offence with an average penalty of 259 euros, according to a study carried out by the OCU consumers group in Spain.

The report reveals that the number of fines imposed last year for this offence was very low (in Pamplona, Gijón, Lérida and Valencia it was zero) and the average amount collected is "almost anecdotal" at 1,794 euros on average - except in the case of Malaga, with a total of 166 penalties and more than 40,000 euros collected for the public coffers.

One of the difficulties is tracing the owners of the dogs to collect the fine, a problem that could be overcome by having a mandatory canine genetic database that allows the owner to be identified through a sample of blood or saliva from their pet.

Luis Medina-Montoya at Malaga city council acknowledges that the canine DNA analysis has been "very effective" in punishing offenders. “We believe it will be the pet identification system of the future. No matter how many awareness campaigns we do, in the end people only understand when you hit their pocket," he says.

Malaga and Zaragoza are the first provincial capitals that have used this DNA database system to improve the cleanliness of their streets, in addition to a score of small towns, mostly in Catalonia and Valencia. It would also allow authorities to locate the owners of lost, abandoned or abused dogs.

The procedure is very simple. Dog owners have to take their pets to a vet, where a blood or saliva sample is taken, which is then associated with its microchip identification number.

"The sample is sent to a laboratory and the genotype is registered in the municipal database," says Noelia Díaz, vice secretary of the Official College of Veterinarians of Malaga, pioneers in this canine identification system.

The analysis costs between 35 and 45 euros on average. “Some towns subsidise it, for a period of time, to encourage people to comply with the obligation to register their dogs. After the deadline, the owner must pay the full cost of the analysis," explains Pablo Muñiz Gabilondo, author of an exhaustive study on how the issue of dog poop is managed in the different Spanish towns.

He says, "The genetic profile of each animal is unique. If the sample collected on the street contains more than one DNA string (for example, because another dog has peed on someone else's poop), it is rejected.”

The majority of towns recover the cost of running the schemes through fines. Of the 87 samples collected in Malaga during the months of January and February of this year, at a cost to the town hall coffers of 3,045 euros, the 16 positive results translated into 3,472 euros of income in the form of fines.