The great Irish mammal watch

CITIZEN SCIENTISTS are being encouraged to help build a national picture of the dozens of mammal species with which we share this island. Sightings of mammals are being recorded, with more than 5,000 logged so far, to compile an Atlas of Mammals in Ireland.

Members of the public, amateur naturalists and scientists are asked to send details of mink, bottlenose dolphin or whatever else they see to the National Biodiversity Data Centre. It will help track non-natives such as mink and Irish species such as stoat.

The centre chose mammals for its first atlas project because, though common and often observed, “there is no or little data in terms of their distribution”, says Liam Lysaght, director of the centre, which has just released its annual report.

The task now is to see where our terrestrial and marine mammals live, plot them on the online atlas and promote mammal recording among the public.

“We now have a system in place where we can plot the distribution of say the blue whale and the pygmy shrew,” says Lysaght. Existing and historic data is also being collated to get a picture up to 2010.

In future, anyone who observes a wild mammal can submit details via an online form. Some unusual ones have rolled in. “We have had sightings of wild boar, muntjac, ferret, even chipmunks. They would all be verified before being accepted,” Lysaght explains.

It is surprising how little we know about some species. It was thought hedgehogs might reside more in suburban areas, as this is where people most frequently encountered them, but not so, says Lysaght. “The project is showing that they are widely distributed, but probably avoiding the uplands and wetter areas.”

Some introduced species, notably American mink and brown rats, can devastate nesting freshwater birds and seabirds, especially on islands, says Niall Hatch of Birdwatch Ireland.

We don’t know much about mink distribution, which zoologist Ian Montgomery of Queen’s University Belfast says is best described as scattered.

“It is difficult to estimate the abundance of species such as mink, which are quite secretive. They live along rivers in fairly thick vegetation so you can easily overlook them,” he says.

“They eat small mammals and birds as well as aquatic material, so they’ve a plentiful food supply. There is no reason why they shouldn’t be present in any part of the island. They’ve had time to spread everywhere.”

With recorded sightings, the atlas may fill in some blanks in mink distribution when the catalogue is completed – planned for 2016.

Each of Ireland’s 60-plus mammal species has been assigned a “champion” – a designated phone-a-friend expert for the centre. Zoologist Paddy Sleeman of University College Cork is confident that the project will tell us more about Irish stoats, which he champions.

We can say “absolutely nothing” definitive about the distribution of this small carnivore in Ireland, he says. “They seem to be abundant at rural rubbish dumps, in coastal deciduous woodlands and where there are a large number of rabbits.”