It is a well known fact that spiders are insectivorous and part of their diet also includes plant material like pollen. But not everyone knows that spiders like to go for fishing too. According to a study conducted by Martin Nyffeler who is a spider expert and Zoologist at the University of Basel, Switzerland and Bradley Pusey, a fish expert coming from the University of Western Australia discovered that a few large sized spider varieties include small fish in their diet too. They have recorded incidents of spiders hunting fish from all the continents except Antartica. Majority of such semi aquatic spiders hunting and feeding on freshwater small sized fishes like mosquitofish, have been observed in North America around the wetlands of Florida.
The researchers together have observed five families of spider species that hunt small sized fishes in the wild and three more spider families, hunting fishes under laboratory environment. According to Martin Nyffeler, this is a unique behavior of spiders which suggest that they might be occasionally preying fish which are high in nutritional value.
Such spiders are known as semi aquatic spiders and are found to reside near shallow water ponds, streams and swamps. Certain spiders are known to have the ability to swim, dive and even walk on the surface of water. They are equipped with neurotoxins and enzymes, which helps them in hunting and later in digesting fish that are generally heavier and larger than the spiders themselves. Researchers observed that while hunting spiders first secure their hind legs to a plant or a stone, while the front legs remains on the water surface, ready for the kill. The caught fish is then taken to a dry place and then the spiders begin to feed on its kill, which can last for several hours at a stretch. The fish that are usually hunted by the spiders are nearly twice in length as compared to their arachnid predators.
But all the arachnophobes need not to worry as these spiders do not posses any threat to humans and its only in sci-fi movies that they rise above humans and rule the planet.
Source: University of Basel