Dogs have a real nose for wildlife conservation

In fieldwork situations, our canine friends worked faster than people and found four times as many scat samples.

Dogs were trained to discriminate between the scats of local wild species. The trained detection dogs distinguished between species 'with up to 100% accuracy', even when the target species 'were closely related and fed with the same diet'.

Garda sniffer-dog Bouncer discovered €17,500 worth of cocaine recently. The drugs were hidden in a car. Dogs with jobs work as security-guards, guides for sight-impaired people and companions to people who suffer from loneliness and depression.

A study published in 2019 found that dogs can detect cancer tumours with almost 97% accuracy just by smelling blood samples. Researchers at MIT are seeking canine help to develop algorithms so that future smart-phones can function as electronic noses.

Dogs also have wildlife conservation roles. In a piece of ground-breaking research, Emma Sheedy and Colin Lawton of NUI Galway showed that the presence of pine martens helps control grey squirrel numbers. This finding has thrown a lifeline to our native red squirrels, which are being ousted by the alien greys.

Richard Collins: 'Dogs can detect cancer tumours with almost 97% accuracy just by smelling blood samples.'

Sheedy walked over 1,000km searching for marten ‘poo’ for her research. Scats are very difficult to locate, so a trained sniffer-dog was brought in from England. It located about eight scats for everyone she found.

Dogs played a similar role in a German project. Otters are secretive, nocturnal animals and their presence is difficult for us to detect. Like most mammals, they use scent to communicate, leaving smelly markers everywhere, which dogs easily detect. The researchers used to collect scats visually while walking along river banks, but poo deposited by other species complicated the procedure.

“In 2010-2012, over 10% of all samples collected and visually identified as otter came from mink,” the researchers noted, and a total of 34% of the samples belonged to fish-eating predators other than otters.

Analysing such samples is wasteful of resources and expensive. The researchers needed to find a way to discriminate between scats in the field, so they turned to dogs for help.

Annegret Grimm-Seyfarth, and colleagues at the UFZ Centre for Environmental Research, compared the poo-finding performance of dogs with that of human searchers.

Dogs were trained to discriminate between the scats of local wild species. They were then tested against humans along stretches of a river where otters were present. Each scat found was photographed for identification. The trained detection dogs, the results showed, distinguished between species “with up to 100% accuracy”, even when the target species “were closely related and fed with the same diet”.

The average accuracy of all trained dogs was 95%, better than that of the best human searchers, who only achieved an accuracy of 89%. The overall accuracy of the trained personnel tested was 58%.

These results were obtained in an experimental situation. In real fieldwork situations, dogs worked faster than people and found four times as many scat samples than human searchers over the same test period. The colour and size of a scat did not matter to dogs, whereas the humans tended to find mainly larger and more lightly coloured poo, potentially biasing the data obtained.

In their report just published, Grimm-Seyfarth and colleagues write that “while humans have about six million olfactory receptors, a herding dog has more than 200 million, a beagle even more than 300 million of them”. The paper reviews the worldwide deployment of dogs in conservation and compares the performances of various breeds.

• Annegret Grimm-Seyfarth et al, ‘Detection Dogs in Nature Conservation’, ‘Methods in Ecology and Evolution’, 2021.