Spiders are giving new meaning to the phrase all-you-can-eat, according to a new report published in the journal The Science of Nature.
A team of Swiss and Swedish scientists found that the predatory arachnids eat an estimated 400 to 800 million metric tons of prey each year. That’s at least equal to – or possibly double – what all the humans on earth consume in meat and fish annually!
The critters’ appetites are even larger than those of whales, the study finds. The sea mammals munch through approximately 280 million to 500 million tons of prey per year.
Most of the more-than-45,000 species of spider eat insects or collembola, the small, insect-like creatures also known as springtails.
“Our calculations let us quantify for the first time on a global scale that spiders are major natural enemies of insects,” said researcher Martin Nyffeler, from the University of Basel.
“In concert with other insectivorous animals such as ants and birds, they help to reduce the population densities of insects significantly.”
However, larger tropical species do occasionally devour vertebrates, such as frogs, lizards, fish and small mammals.
“Spiders thus make an essential contribution to maintaining the ecological balance of nature,” Nyffeler added.
“We hope that these estimates and their significant magnitude raise public awareness and increase the level of appreciation for the important global role of spiders in terrestrial food webs.”