A healthy coral reef ecosystem with sharks off Jarvis Island, an uninhabited island located in the South Pacific Ocean. A loss of these large predators can alter the patterns of predation and herbivory, ultimately leading to an coral system where reef-building corals and coralline algae lose their competitive advantage. CREDIT: Brian Zgliczynski

The loss of top predators, such as lions, wolves and sharks, is causing unpredictable changes to food chains around the world, according to a review written by 24 scientists.

These animals, called apex predators, play a crucial role in ecosystems, and their disappearance — often due to hunting by humans and loss of habitat — can lead to changes in vegetation, wildfire frequency, infectious diseases, invasive species, water quality and nutrient cycles, according to the authors led by James Estes, a professor of ecology and evolutionary biology at the University of California, Santa Cruz.

to read more, go to:    http://www.livescience.com/15051-apex-top-predators-loss-food-chain-ecosystem.html