In a study published in the November 3 issue of the journal, Science, an international group of ecologists and economists show that the loss of biodiversity is profoundly reducing the ocean's ability to produce seafood, resist diseases, filter pollutants, and rebound from stresses such as over fishing and climate change. The study reveals that every species lost causes a faster unraveling of the overall ecosystem. Conversely every species recovered adds significantly to overall productivity and stability of the ecosystem and its ability to withstand stresses.
"Whether we looked at tide pools or studies over the entire world's ocean, we saw the same picture emerging," says lead author Boris Worm of Dalhousie University. "In losing species we lose the productivity and stability of entire ecosystems. I was shocked and disturbed by how consistent these trends are - beyond anything we suspected."
The four-year analysis is the first to examine all existing data on ocean species and ecosystems, synthesizing historical, experimental, fisheries, and observational datasets to understand the importance of biodiversity at the global scale.
The results reveal global trends that mirror what scientists have observed at smaller scales, and they prove that progressive biodiversity loss not only impairs the ability of oceans to feed a growing human population, but also sabotages the stability of marine environments and their ability to recover from stresses. Every species matters.
"For generations, people have admired the denizens of the sea for their size, ferocity, strength or beauty. But as this study shows, the animals and plants that inhabit the sea are not merely embellishments to be wondered at," says Callum Roberts, a Professor at the University of York, who was not involved in the study. "They are essential to the health of the oceans and the well-being of human society."