Featured Research

from universities, journals, and other organizations

Invasive alien predator causes rapid declines of European ladybugs

Date:
February 6, 2012
Source:
Centre for Ecology & Hydrology
Summary:
A new study provides compelling evidence that the arrival of the invasive non-native harlequin ladybird (ladybug) to mainland Europe and subsequent spread has led to a rapid decline in historically-widespread species of ladybird in Britain, Belgium and Switzerland. The analysis is further evidence that harlequin ladybirds are displacing some native ladybirds, most probably through predation and competition.

One common species, the large seven-spot ladybird, has retained a stable distribution and abundance across Europe despite the arrival of the harlequin.
Credit: Richard Comont/Centre for Ecology & Hydrology

A new study provides compelling evidence that the arrival of the invasive non-native harlequin ladybird (ladybug) to mainland Europe and subsequent spread has led to a rapid decline in historically-widespread species of ladybird in Britain, Belgium and Switzerland.

The analysis, recently published in the scientific journal Diversity and Distributions, is further evidence that Harlequin ladybirds are displacing some native ladybirds, most probably through predation and competition. The research provides one of the first demonstrations of a strong link between the arrival of an invasive alien species and a decline in native biodiversity at a large spatial-scale.

The study was led by Dr Helen Roy from the UK's Centre for Ecology & Hydrology and Tim Adriaens from the Research Institute for Nature and Forest (INBO) in Belgium. The research team included 20 scientists from 11 institutions located in five European countries.

Invasive alien species are internationally recognized as one of the five major drivers of biodiversity loss, but few causal relationships between their arrival in a new region and subsequent species declines have been documented in the scientific literature.

The Harlequin was first found in Belgium in 2001 and in Britain and Switzerland in 2004. Previously its arrival had been predicted to threaten native biodiversity but, until now, the effect on native species had not been quantified.

By examining thousands of ladybird distribution records (presence in a 1km2 grid cell) collected through public participatory surveys in Britain and Belgium the research team was able to show that five (Belgium) and seven (Britain) out of the eight species studied declined substantially since the arrival of the Harlequin. One common species, the large 7-spot ladybird, has retained a stable distribution and abundance across Europe despite the arrival of the Harlequin.

A particularly dramatic decline in the 2-spot ladybird was noted, showing a decline by 30% in Belgium and 44% in Britain over the five years following the arrival of the Harlequin. Similar patterns of decline were found in ladybird abundance data (number of individuals) collated from systematic surveys of deciduous trees in Belgium, Britain and Switzerland. The 2-spot ladybird is now near the threshold of detection in habitats in which it was previously common. The Harlequin ladybird is a deciduous tree-dwelling species and its population increase has coincided with declines in species that share the same niche.

Lead author Dr Helen Roy of the UK's Centre for Ecology & Hydrology said, "This study provides strong evidence of a link between the arrival of the Harlequin ladybird and declines in other species of ladybird, a result that would not have been possible without the participation of so many members of the public gathering ladybird records across Britain, Belgium and Switzerland."

Co-author Tim Adriaens from the Research Institute for Nature and Forest (INBO) in Belgium said, "Within the insect world ladybirds are as iconic as panda bears and they provide an incredibly useful ecological function by keeping aphids in check. At the continental scale the arrival of the Harlequin could impact on the resilience of ecosystems and severely diminish the vital services that ladybirds deliver."

Co-author Dr Marc Kenis from CABI Europe-Switzerland, who is leading studies on the Harlequin in Switzerland, said, "It is essential that our long-term investigations on the decline of native ladybird species are continued, as we need to know whether this decline will persist and whether some species are at risk of local extinction. Furthermore, we need to find specific methods to better investigate the potential decline of rarer species, which were hardly noticed in our general surveys before the arrival of the invasive species."

Co-author Dr Peter Brown from Anglia Ruskin University, UK, said, "Long-term datasets such as those used in this work (and our recent atlas of ladybirds of Britain and Ireland) are invaluable. We are extremely grateful to the thousands of volunteer recorders who have contributed their ladybird findings to the surveys."


Story Source:

The above story is based on materials provided by Centre for Ecology & Hydrology. Note: Materials may be edited for content and length.


Journal Reference:

  1. Helen E. Roy, Tim Adriaens, Nick J. B. Isaac, Marc Kenis, Thierry Onkelinx, Gilles San Martin, Peter M. J. Brown, Louis Hautier, Remy Poland, David B. Roy, Richard Comont, Renι Eschen, Robert Frost, Renate Zindel, Johan Van Vlaenderen, Oldřich Nedvěd, Hans Peter Ravn, Jean-Claude Grιgoire, Jean-Christophe de Biseau, Dirk Maes. Invasive alien predator causes rapid declines of native European ladybirds. Diversity and Distributions, 2012; DOI: 10.1111/j.1472-4642.2012.00883.x

Cite This Page:

Centre for Ecology & Hydrology. "Invasive alien predator causes rapid declines of European ladybugs." ScienceDaily. ScienceDaily, 6 February 2012. <www.sciencedaily.com/releases/2012/02/120206214226.htm>.
Centre for Ecology & Hydrology. (2012, February 6). Invasive alien predator causes rapid declines of European ladybugs. ScienceDaily. Retrieved September 16, 2014 from www.sciencedaily.com/releases/2012/02/120206214226.htm
Centre for Ecology & Hydrology. "Invasive alien predator causes rapid declines of European ladybugs." ScienceDaily. www.sciencedaily.com/releases/2012/02/120206214226.htm (accessed September 16, 2014).

Share This



More Earth & Climate News

Tuesday, September 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Scientists Examine Colossal Squid

Raw: Scientists Examine Colossal Squid

AP (Sep. 16, 2014) — Squid experts in New Zealand thawed and examined an unusual catch on Tuesday: a colossal squid. It was captured in Antarctica's remote Ross Sea in December last year and has been frozen for eight months. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Man Floats for 31 Hours in Gulf Waters

Man Floats for 31 Hours in Gulf Waters

AP (Sep. 16, 2014) — A Texas man is lucky to be alive after he and three others floated for more than a day in the Gulf of Mexico when their boat sank during a fishing trip. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Researchers Explore Shipwrecks Off Calif. Coast

Researchers Explore Shipwrecks Off Calif. Coast

AP (Sep. 16, 2014) — Federal researchers are exploring more than a dozen underwater sites where they believe ships sank in the treacherous waters west of San Francisco in the decades following the Gold Rush. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Isolated N. Korea Asks For International Help With Volcano

Isolated N. Korea Asks For International Help With Volcano

Newsy (Sep. 16, 2014) — Mount Paektu volcano in North Korea is showing signs of life and there's not much known about it. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

      Technology News



      Save/Print:
      Share:  

      Free Subscriptions


      Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

      Get Social & Mobile


      Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

      Have Feedback?


      Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
      Mobile iPhone Android Web
      Follow Facebook Twitter Google+
      Subscribe RSS Feeds Email Newsletters
      Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins