Featured Research

from universities, journals, and other organizations

Reducing numbers of one carnivore species indirectly leads to extinction of others

Date:
February 28, 2013
Source:
University of Exeter
Summary:
Previous studies have shown that carnivores can have indirect positive effects on each other, which means that when one species is lost, others could soon follow. Biologists have now found that reducing the numbers of one species of carnivore can lead to the extinction of others.

Previous studies have shown that carnivores can have indirect positive effects on each other, which means that when one species is lost, others could soon follow. A team from the University of Exeter and the University of Bern has now found that reducing the numbers of one species of carnivore can lead to the extinction of others.

Published online February 28, 2013 in the journal Ecology Letters, the study shows that simply reducing the population size of one carnivore can indirectly cause another similar species to become extinct. The research shows that changes in population size, as well as extinction, can create ripple effects across sensitive food webs with far-reaching consequences for many other animals.

The research shows that species could suffer just as much from harm to another species as from being under direct threat themselves. This adds weight to growing evidence that a 'single species' approach to conservation, for example in fisheries management, is misguided. Instead the focus needs to be holistic, encompassing species across an entire ecosystem.

The researchers assembled experimental ecosystems with three species of parasitic wasps, along with the three types of aphids on which each wasp exclusively feeds. They set up four sets of tanks each containing the three aphid and three wasp species and allowed the populations to establish for eight weeks. Over the next 14 weeks (seven insect generations) the researchers removed a proportion of the wasps from three of the sets of tanks every day -- one species from each set. The fourth set had no wasps removed.

The team found that the partial removal of one wasp species led indirectly to the extinction of other wasp species. In the absence of one wasp species, the aphid it preyed upon grew in numbers. All three species of aphid feed on the same plant so increased competition for food led to changes in sizes of the aphid populations. However no aphid species went extinct and so the indirect extinctions of the wasps were not the result of extinction of their prey. Rather, it is likely that the wasps that went extinct had difficulty searching for suitable prey among large numbers of unsuitable ones.

Lead researcher Dr Frank van Veen of the University of Exeter's Centre for Ecology and Conservation said: "We have shown that the complex ripple effect of a change in population size across food webs is more sensitive than previously thought and that a reduction in the numbers of one carnivore can lead to the extinction of another carnivore species. We also found evidence that the initial indirect extinction can itself trigger further ones, potentially leading to a cascade of extinctions, like dominoes toppling over."

"The insect system is handy for experimentation but the same principles apply to any ecosystem, from mammals in the Serengeti to the fish in our seas. It clearly shows that we should have an ecosystem-based approach to conservation and to the management of fish stocks and other natural resources."

The research team has recently been awarded a 470K grant by the Natural Environment Research Council (NERC) to extend this research at a larger scale.


Story Source:

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


Journal Reference:

  1. Dirk Sanders, Louis Sutter and F. J. Frank van Veen. The loss of indirect interactions leads to cascading extinctions of carnivores. Ecology Letters, 28 FEB 2013 DOI: 10.1111/ele.12096

Cite This Page:

University of Exeter. "Reducing numbers of one carnivore species indirectly leads to extinction of others." ScienceDaily. ScienceDaily, 28 February 2013. <www.sciencedaily.com/releases/2013/02/130228124144.htm>.
University of Exeter. (2013, February 28). Reducing numbers of one carnivore species indirectly leads to extinction of others. ScienceDaily. Retrieved April 17, 2014 from www.sciencedaily.com/releases/2013/02/130228124144.htm
University of Exeter. "Reducing numbers of one carnivore species indirectly leads to extinction of others." ScienceDaily. www.sciencedaily.com/releases/2013/02/130228124144.htm (accessed April 17, 2014).

Share This



More Plants & Animals News

Thursday, April 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Change of Diet Helps Crocodile Business

Change of Diet Helps Crocodile Business

Reuters - Business Video Online (Apr. 16, 2014) Crocodile farming has been a challenge in Zimbabwe in recent years do the economic collapse and the financial crisis. But as Ciara Sutton reports one of Europe's biggest suppliers of skins to the luxury market has come up with an unusual survival strategy - vegetarian food. Video provided by Reuters
Powered by NewsLook.com
Could Even Casual Marijuana Use Alter Your Brain?

Could Even Casual Marijuana Use Alter Your Brain?

Newsy (Apr. 16, 2014) A new study conducted by researchers at Northwestern and Harvard suggests even casual marijuana use can alter your brain. Video provided by Newsy
Powered by NewsLook.com
Thousands Of Vials Of SARS Virus Go Missing

Thousands Of Vials Of SARS Virus Go Missing

Newsy (Apr. 16, 2014) A research institute in Paris somehow misplaced more than 2,000 vials of the deadly SARS virus. Video provided by Newsy
Powered by NewsLook.com
Raw: Three Rare White Tiger Cubs Debut at Zoo

Raw: Three Rare White Tiger Cubs Debut at Zoo

AP (Apr. 16, 2014) The Buenos Aires Zoo debuted a trio of rare white Bengal tiger cubs on Wednesday. (April 16) 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:
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