In pictures: Ireland's 'most unwanted' list of invasive species

But what should you do if you see any of them? Read on…

DOZENS OF PLANT and animal species have been identified as invasive species – or potentially invasive – in Ireland. These flora and fauna are putting native Irish species under threat by attacking them directly or competing for their food sources.

Collette O’Flynn of Invasive Species Ireland told TheJournal.ie that the species were identified through the risk assessment of hundreds of plants and animals, and that they can affect human health (such as the giant hogweed in the slideshow below) or have an economic impact.

O’Flynn said that more species are being highlighted as invasive, but that this could be down to the fact that people are looking out for them and reporting them more. Some species have been introduced intentionally, she said. “Around the 1900s, there would have been a lot of plants were introduced into the country and some like giant hogweed have become invasive. There was a culture of ornamental plants and the more exotic the better.”

“There are hundreds [of plant species] introduced into Ireland every year and it’s only a fraction of those that become invasive – about 1 per cent.” A lot of introduced species decline at once, she says, due to climatic conditions, but more recently it is the aquatic species such as pond plants that are becoming invasive.

So what should you do if you see an invasive species?

Basically, don’t rush out to squash/remove/kill the species in question until you’ve checked it out with the relevant authorities because a. some plants spread more quickly if you haven’t removed them correctly and b. you may be confusing the species you’re looking at with the native variety.

“The harlequin ladybirds eat our native ladybirds and other species as well. They’re so variable in how they look and people could get it confused with the native species,” O’Flynn warned. “And if someone thought they had it but it was the wrong one, then they could be destroying the native species.”

She recommends contacting Invasive Species Ireland (details here) with a description of where, when and what was found, and if possible to get a photo. The organisation will then contact the relevant authorities who will advise on how to tackle that species in your situation.

Check out some of the invasive species which have become established in Ireland:

In pictures: Ireland's 'most unwanted' list of invasive species

Previous 1 / 12Next

Muntjac Deer (Muntiacus reevesi)
Originally from China, this small, stocky deer damages new growth in forests through overgrazing and can harbour diseases and parasites which impact on domestic livestock. (Image by shimgray on Flickr)
Zebra Mussel (Dreissena polymorpha)
These mussels, which most likely came here on the hulls of imported boats, can cause changes in water nutrient cycles, impacting on native mussel species and fish. They can also block boat engines and water intake pipes. (Image by andres musta on Flickr)
Wild Boar (Sus scrofa)
Wild boar (which used to be native here but became extinct in prehistoric times) cause serious damage to crops and gardens by uprooting and eating plants. (Image of a cute baby boar by Dominique Pipet on Flickr)
Ruddy Duck (Oxyura jamaicensis)
This freshwater diving duck is threatening the survival of the white-headed duck, which it breeds with. (Image by Paolo Bertinetto on Flickr)
Ferral Ferret (Mustela furo)
Ferret can take a high toll on bird species, particularly on smaller islands. According to Invasive Species Ireland, it was introduced to Rathlin Island to control the rabbit population, but has since become an established invasive species. (Image by neusitas on flickr)
Hottentot Fig (Carpobrotus edulis)
Introduced originally for garden ornamentation, this plant can adversely affect dune environments while reducing the pH of the soil. (Image by cliff1066â„¢ on Flickr)
Harlequin Ladybirds (Harmonia axyridis)
The harlequin ladybird's appearance changes in colour (from yellowish to red) and in the number of spots it carries, making it difficult to identify from native ladybirds - which they eat. (Image by deargdoom57 on Flickr)
Grey Squirrel (Sciurus carolinensis)
The grey squirrel threatens the protected native red squirrel species by competing for food and space. (Image by Bobolink on Flickr)(Image by Bobolink on Flickr)
Giant Rhubarb (Gunnera tinctoria)
Despite the name, this isn't actually related to rhubarb (it just looks like it). Native to South America, the plant can lead to the local extinction of other plant species, as well as blocking drainage ditches. (Image by Drew Avery on Flickr)
Giant Hogweed (Heracleum mantegazzianum)
A member of the parsley or carrot family, this plant is native to Asia and can grow up to 6 metres in height. The toxins in the plant's sap can cause human skin to blister and contributes to riverbank erosion. It also pushes out native plants, impacting on the animals that rely on those plants for food. (Image by debs-eye on flickr)
Brown Rat (Rattus norvegicus)
Meanwhile, the brown (or Norway) rat has brown fur on its back and grey fur on its belly. It has also been observed attacking both adult birds and chicks and has been recorded hunting more species than the black rat. (Image by by anemoneprojectors on Flickr)
Black Rat (Rattus rattus)
The black rat has large hairless ears and has been seen attacking birds and killing chicks, leading to the decline or local extinction of bird species around the world. As well as eating birds and small animals, the rats also eat leaves, seeds, flowers, bark and the stems of plants, damaging ecosystems. (Image by GlennFleishman on Flickr)

A mix of advertising and supporting contributions helps keep paywalls away from valuable information like this article. Over 5,000 readers like you have already stepped up and support us with a monthly payment or a once-off donation.

For the price of one cup of coffee each week you can make sure we can keep reliable, meaningful news open to everyone regardless of their ability to pay.

Support us Learn More

In pictures: Ireland's 'most unwanted' list of invasive species

Muntjac Deer (Muntiacus reevesi)

Zebra Mussel (Dreissena polymorpha)

Wild Boar (Sus scrofa)

Ruddy Duck (Oxyura jamaicensis)

Ferral Ferret (Mustela furo)

Hottentot Fig (Carpobrotus edulis)

Harlequin Ladybirds (Harmonia axyridis)

Grey Squirrel (Sciurus carolinensis)

Giant Rhubarb (Gunnera tinctoria)

Giant Hogweed (Heracleum mantegazzianum)

Brown Rat (Rattus norvegicus)

Black Rat (Rattus rattus)

Making a difference

A mix of advertising and supporting contributions helps keep paywalls away from valuable information like this article. Over 5,000 readers like you have already stepped up and support us with a monthly payment or a once-off donation.