The advantages of population recovery and population growth of sea otters, top predators of the Pacific coast of Canada, outweigh the losses to commercial fishing of their prey — crabs, sea urchins and bivalves are reported in Science. With the return of these animals in the 37 percent increase the productivity of their ecosystems, and the profit from eco-tourism, which will provide fans of sea otters, will be six times higher than the monetary loss from a reduction in seafood production. This is one of the first studies, which comprehensively considered the economic impact of restoring the populations of rather large predator.
Over the past 100-150 years many terrestrial ecosystems were left without their main predators: someone was killed for fur, some for damage, which inflicted a carnivorous animal, and someone unintentionally deprived of suitable habitat or prey base. In many countries now have programs to return these species (e.g., wolf in Yellowstone national Park) to the appropriate natural community.
However, while predators do not exist in the ecosystem, it can significantly change, not least due to man. So, off the coast of British Columbia for a long time in industrial-scale catch of sea urchins, crabs (Cancer magister) and bivalves (Gaidukov). They all serve as food for sea otters (Enhydra lutris; it is also called a sea otter, even though it’s not an otter), the size of which the canadian coast in the XVIII–XIX centuries fell nearly to zero: they have been hunted for pelts. Now sea otters re-colonize the waters off of Vancouver island, and people have to understand how the neighborhood with these animals will affect the marine fishery.
Edward Gregr (Edward Gregr) from the University of British Columbia and his colleagues evaluated the changes that occur when restoring the population of sea otters off the coast of Vancouver island, and modeled the impact of sea otters on the ecology and economy of the region. They considered the place of animals in the food web and based on that figured out, how the biomass of brown algae, plankton, benthos (bottom organisms), the inhabitants of the pelagial (deep water) and sequestration of atmospheric carbon dioxide when in the ecosystem appear to be a sea otter. Scientists have determined how many million canadian dollars per year will bring different industries or will Rob them of the return of predators.