1 Tahrcountry Musings: Live and let live - Predator species help each other while competing for a single prey

Wednesday, September 10, 2008

Live and let live - Predator species help each other while competing for a single prey

All of us are familiar with apportionment and rationing when there is a resource crunch. Nature resorting to this ploy might sound a wee bit farfetched. But this is exactly what scientists from Sweden and Netherlands have found out in their pursuit of intricacies of predator prey relationships. I was fascinated to read the paper “Stage-specific predator species help each other to persist while competing for a single prey” by A. M. De Roos et al. It gave me insights in to the myriad and mysterious ways in which nature works. In the wild state prey are usually shared by many predator species. One of the fundamental questions in ecology is how predators coexist while competing for the same prey. De Roos and associates with their research show that competing predator species may not only coexist on a single prey but even help each other to persist if they specialize on different life history stages of the prey. The research comes up with the finding that a predator may not be able to persist at all unless its competitor is also present. Net result is asymmetric increases in the rate of prey maturation and reproduction when predation relaxes competition among prey. This interdependence suggests that the network of feeding interactions in a community is, in fact, an emergent property of the system, which to a large extent arises through self-organization. Part and parcel of this self-organized character of the food web is an inherent fragility whereby the loss of a facilitating predator species may lead to subsequent extinction of some of its guild members, making the community collapse like a house of cards.

Stage-specific predator species help each other to persist while competing for a single prey
A. M. De Roos,T. Schellekens, T. Van Kooten and L. Persson
Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94084, 1090 GB Amsterdam, The Netherlands; and Department of Ecology and Environmental Science, Umeå University, SE-90187 Umeå, Sweden

1 comment:

IndianWildlifeClub said...

In the same vein as your post, Overfishing damages much more than fish populations. Extracting too many fish from an ecosystem can reduce the survival chances of other predators in the marine food web, including populations of marine mammals, seabirds, turtles, sharks and a host of other species.
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