Featured Research

from universities, journals, and other organizations

Introduction of Asian ladybugs into Europe serious mistake, experts say

Date:
July 30, 2012
Source:
Wageningen University and Research Centre
Summary:
In retrospect, introducing the Asian ladybird (ladybug) into Europe was a serious mistake. The insect was introduced some twenty years ago in a conscious attempt to combat aphids. But new research into the invasion of this foreign insect has shown that the disadvantages far outweigh this single advantage. The Asian species is displacing the native European ladybird and has become a pest that can contaminate homes and spoil the taste of wine.

In retrospect, introducing the Asian ladybird into Europe was a serious mistake.
Credit: photos_com / Fotolia

In retrospect, introducing the Asian ladybird into Europe was a serious mistake. The insect was introduced some twenty years ago in a conscious attempt to combat aphids. But research carried out at Wageningen UR (University & Research centre) into the invasion of this foreign insect has shown that the disadvantages far outweigh this single advantage. The Asian species is displacing the native European ladybird and has become a pest that can contaminate homes and spoil the taste of wine.

Related Articles


The researchers concerned have reported their findings in the latest edition of the scientific journal PLoS One.

The Asian ladybird, Harmonia axyridis, which originated in China and Japan, is larger than its European counterpart and has an almost invisible dent towards the rear of its wing cover; the colour and dots are much the same. The foreign insect was introduced into France in the early 90s, and was first used in the Netherlands in around 1996. The Asian ladybird was a formidable weapon in the fight against aphids in greenhouses and on avenue trees, from which lice excrete sticky honeydew onto cars. However, time has shown that these insects, which have very few natural enemies in Europe, are also devouring the native ladybirds. Furthermore, colonies of the Asian variety hibernate in houses and other buildings, where their excrement can cause contamination. Last but least, it has been discovered that when the supply of aphids runs out, this insect has an appetite for grapes and spoils the taste of the wine.

Escape

In order to understand how the Asian species has been able to establish itself in Europe so swiftly and decimate the native ladybird population, PhD student Lidwien Raak from Wageningen University and researcher Marieke de Lange from Alterra, part of Wageningen UR, conducted research into the biology of this invasion. They carried out experiments on both native and Asian ladybird species. Previous laboratory tests had shown that the Asian ladybird would always win a physical fight between the two species. But the researchers from Wageningen wanted to know whether this was also true in the wild. They were keen to discover how often they encounter each other, and whether the native ladybirds could escape. The two devised a clever experiment whereby native and foreign ladybirds were placed on the leaves of lime saplings. Their behaviour was monitored for many hours. The long-term observations generated clear data that is at odds with the results of laboratory experiments. They found that native ladybirds often manage to escape their Asian counterparts by running away or dropping to the ground when under attack. However, if their attempts fail, the highly aggressive Asian ladybirds will devour the two European species and the native Dutch species. This goes a long way to explaining the success of this foreign insect.

Banned

On discovering that introducing Asian ladybirds had been a mistake, use of these insects in Europe was banned. Unfortunately, populations had already become well-established in many European countries. The best way to tackle the nuisance caused by non-native animals and plants is to introduce natural enemies. But this too can be a risky business, which is why the Netherlands has asked Wageningen University and the Plant Protection Service to draw up an environmental risk analysis for the natural enemies of non-native species.


Story Source:

The above story is based on materials provided by Wageningen University and Research Centre. Note: Materials may be edited for content and length.


Journal Reference:

  1. C. Lidwien Raak-van den Berg, Hendrika J. De Lange, Joop C. Van Lenteren. Intraguild Predation Behaviour of Ladybirds in Semi-Field Experiments Explains Invasion Success of Harmonia axyridis. PLoS ONE, 2012; 7 (7): e40681 DOI: 10.1371/journal.pone.0040681

Cite This Page:

Wageningen University and Research Centre. "Introduction of Asian ladybugs into Europe serious mistake, experts say." ScienceDaily. ScienceDaily, 30 July 2012. <www.sciencedaily.com/releases/2012/07/120730094916.htm>.
Wageningen University and Research Centre. (2012, July 30). Introduction of Asian ladybugs into Europe serious mistake, experts say. ScienceDaily. Retrieved October 31, 2014 from www.sciencedaily.com/releases/2012/07/120730094916.htm
Wageningen University and Research Centre. "Introduction of Asian ladybugs into Europe serious mistake, experts say." ScienceDaily. www.sciencedaily.com/releases/2012/07/120730094916.htm (accessed October 31, 2014).

Share This



More Earth & Climate News

Friday, October 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

How A Chorus Led Scientists To A New Frog Species

How A Chorus Led Scientists To A New Frog Species

Newsy (Oct. 30, 2014) A frog noticed by a conservationist on New York's Staten Island has been confirmed as a new species after extensive study and genetic testing. Video provided by Newsy
Powered by NewsLook.com
Raw: Hawaii Lava Approaching Village Road

Raw: Hawaii Lava Approaching Village Road

AP (Oct. 30, 2014) The lava flow on the Big Island of Hawaii was 225 yards from Pahoa Village Road on Wednesday night. The lava is slowing down but still approaching the village. (Oct. 30) Video provided by AP
Powered by NewsLook.com
Endangered Carpathian Ponies Are Making a Comeback in Poland

Endangered Carpathian Ponies Are Making a Comeback in Poland

AFP (Oct. 29, 2014) At the foot of the rugged Carpathian mountains near the Polish-Ukrainian border, ranchers and scientists are trying to protect the Carpathian pony, known as the Hucul in Polish. Duration: 02:17 Video provided by AFP
Powered by NewsLook.com
Deadly Mudslide in Sri Lanka Buries Houses

Deadly Mudslide in Sri Lanka Buries Houses

AP (Oct. 29, 2014) A mudslide triggered by monsoon rains buried scores of workers' houses at a tea plantation in central Sri Lanka on Wednesday, killing at least 10 people and leaving more than 250 missing, an official said. (Oct. 29) Video provided by AP
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:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

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