New research suggests the extinction of one carnivorous species could cause other predators to also be wiped out.
The new study backs up the idea of "horizontal extinction cascades," in which the extinction of a species at the top of the food chain could have a ripple effect and trigger the extinction of other major carnivores, the University of Exeter reported.
The findings could have important implications for the future of conservation. The results deliver the message that instead of focusing on a single endangered species, conservationists should adopt an entirely new system that includes the protection of other related predators.
To make their findings, a team of researchers set up experimental communities with complex food webs in large outdoor field cages. The cages contained several aphids and predatory wasps.
"This is a unique experiment. Usually these research questions are tackled with theoretical approaches and researchers focus on extinctions after the loss of food species. This is the first time anyone has looked at mechanisms of horizontal extinction cascades in a natural large field experiment," said Dirk Sanders from the Centre for Ecology and Conservation at the University's Penryn campus in Cornwall.
The experiment showed that removing one wasp species led to an increased rate of extinction among other wasps in the environment. When a wasp species disappeared, populations of its favorite aphid prey grew immensely, overtaking other aphid species and making it difficult for existing wasp species to locate their prey of choice.
"Such extinction cascades are seen as a major thread to biodiversity but it is very hard to get data about this happening in nature, due to the many different influences. Knowing how such extinction cascades can happen gives us a better understanding and helps us to predict when they might happen. If we want to protect an endangered carnivore species, for example, we might need to protect other predators around it, which is quite an important message," Sanders concluded.
The findings were published in a recent edition of the journal Current Biology.
