'Dirty dozen' invasive species threaten UK

May 01, 2013

Parts of the UK are at greater risk of invasion by non-native aquatic species than previously thought, according to new research. The first to include human factors in models used to predict where invasive species will arrive and spread, the study shows the Thames, Anglian and Humber river basins are most vulnerable.

The researchers, Dr Bellinda Gallardo and Dr David Aldridge from the University of Cambridge, focussed on the 'dirty dozen' – a group of high-risk invasive aquatic . Some, like the killer shrimp (Dikerogammarus villosus) and the bloody red mysid (Hemimysis anomala) are already in UK but have yet to spread. Others, such as the (Corbicula fluminalis) and the marmokrebs, a crayfish (Procambarus fallax) may not yet have arrived.

Working with Species Distribution Models, which are routinely used to predict which regions most suit invasive species, the Cambridge pair made the models more accurate by including human factors such as population density, land-use and proximity to ports. Traditionally, the models are based on environmental conditions such as temperature and rainfall.

According to Dr Gallardo: "Invasive species need to be in the right place at the right time; they need the right environmental conditions, but they also need a helping hand from humans. This can happen intentionally, for example through introduction of commercial fish, or accidentally via hulls of boats, fishing equipment, or ."

The role of humans, plus invasive species' great adaptability, make predicting their spread challenging. By including both human and environmental factors in the models, the researchers found the risk of invasion in the UK was increased by 20% in coastal, densely populated areas and places near transport routes, with the Thames, Anglian and Humber river basins at highest risk.

"These already host many aquatic invaders. This is particularly worrying because invasive species often modify their habitat, making it more favourable to other invaders. This can eventually lead to a process known as invasional meltdown," she says.

Tackling the problem is costly. Invasive species are the second biggest threat to biodiversity after habitat loss. Around 12,000 invasive species have already arrived in Europe, where their combined impact on native biodiversity, agriculture, health and the economy costs at least €12 billion a year.

By producing more accurate maps, the study should allow environmental managers and policy makers to target resources at the most invasive species and the areas most under threat. "Effective management of invasive species depends on rapid detection and control. Our maps are fundamental to direct biomonitoring efforts towards areas most suitable for the 'dirty dozen', so they can be detected as soon as possible," Dr Gallardo explains.

"At present, environmental managers and policy makers have few tools to make informed decisions about the risk posed by existing and future invaders. Our study gives them basic information to prioritise management and control decisions regarding 12 of the most worrisome freshwater invasive species."

The study is also timely because of climate change, which might further favour invasive species, she adds: "Invasive species might better adapt to climate change than natives because of their wide environmental tolerance and highly competitive biological traits. And because they usually reproduce rapidly, may be better than native species at resisting and recovering from extreme events."

Explore further: Norfolk Island's endangered Green Parrot numbers on the rise

More information: Bellinda Gallardo and David C. Aldridge (2013). 'The 'dirty dozen': socio-economic factors amplify the invasion potential of twelve high risk aquatic invasive species in Great Britain and Ireland', doi: 10.1111/1365-2664.12079, is published in the Journal of Applied Ecology on 1 May 2013.

add to favorites email to friend print save as pdf

Related Stories

Freshwater Fish Invasions the Result of Human Activity

Feb 05, 2008

Globally, invasive species represent a major threat to native species. A new paper published this week in the open-access journal PLoS Biology shows that, for rivers and lakes, where these invasions occur ...

Climate change invites alien invaders -- Is Canada ready?

Jan 19, 2012

A comprehensive multi-disciplinary synthesis just published in Environmental Reviews reveals the urgent need for further investigation and policy development to address significant environmental, social and economic impact ...

Threatened or invasive? Species' fates identified

Jun 13, 2008

A new ecological study led by a University of Adelaide researcher should help identify species prone to extinction under environmental change, and species that are likely to become a pest.

Using computer models to help our fragile ecosystem

Sep 25, 2012

Global warming is well-known for its effect on the climate. But it also poses a threat to the world's ecosystems. University of Toronto researcher Benjamin Gilbert wants to know more about that process.

Recommended for you

Preserving crucial tern habitat in Long Island Sound

4 hours ago

Great Gull Island is home to one of the most important nesting habitats for Roseate and Common terns in the world. The estimated 1,300 pairs of Roseate terns that summer on the 17-acre island at the eastern ...

California's sea otter numbers holding steady

4 hours ago

When a sea otter wants to rest, it wraps a piece of kelp around its body to hold itself steady among the rolling waves. Likewise, California's sea otter numbers are holding steady despite many forces pushing ...

22 elephants poached in Mozambique in two weeks

18 hours ago

Poachers slaughtered 22 elephants in Mozambique in the first two weeks of September, environmentalists said Monday, warning that killing for ivory by organised syndicates was being carried out on an "industrialised" ...

Pakistan releases smuggled turtles into the wild

23 hours ago

Pakistani officials and environmentalists on Monday released some 200 rare turtles into the River Indus after the reptiles were retrieved from a southwestern Chinese town where they were seized by customs ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

Jeddy_Mctedder
1 / 5 (1) May 01, 2013
There is only one invasive species. Us.
Im all for good stewardship. But we all know how this story goes.
We have and will continue to kill the others so long as we are able. Its our destiny.