When the Wisconsin Department of Natural Resources posted on its Facebook page that giant fishing spiders had been spotted around the state the news was shared more than 10,000 times. More than 2,000 comments were received, including from people posting their own images of the arachnids. Many posters expressed concern and abhorrence. But these are amazing animals with super powers, able to row, gallop, or sail with the wind on water, and they can haul up aquatic animals five times heavier than they are. Two National Geographic Channel videos below demonstrate how fishing spiders snare and eat frogs and tadpoles.
“We have been receiving reports of people finding very large spiders, like the one pictured here on a bluebird house,” the Wisconsin Department of Natural Resources said on its Facebook page. “These are fishing spiders. The most common one we’ve been receiving reports about is the dark fishing spider. They often live next to water and can catch small fish and tadpoles to eat, but they can range inland as well to hunt and lay their eggs. This is a female spider guarding her egg sac.”
What is a fishing spider, and how does it catch prey in water? Water Currents looked into the National Geographic vault to find out what we know about this species. We found a lot, which we are sharing with our followers here. And because it is in the news, we are making the fishing spider our freshwater species of the week.
Spiders in 8 of the world’s 109 arachnid families can catch and consume small fish, National Geographic reported in June 2014. Some of them can even subdue fish five times heavier than they are.
Here’s an excerpt from our article:
These arachnids are nearly everywhere. [A] study, published June 18 in the journal PLOS ONE, says fish-eating spiders can be found on every continent except Antarctica. They’re especially prevalent in warm, oxygen-depleted bodies of water like the wetlands of Florida, where fish are more likely to come to the surface in search of oxygen-rich water.
At least 18 species have now been observed catching fish, including six-spotted fishing spiders (Dolomedes triton) in the United States, pond wolf spiders (Pardosa peudoannulata) in India, and great raft spiders (Dolomedes plantarius) in the United Kingdom.
National Geographic’s Weird & Wild published an article by Mary Bates in June 2014 featuring amazing animals that can walk on water. One of those animals is the fishing spider. Here’s an excerpt of what Bates wrote:
Fishing spiders have several ways of getting around on the water’s surface. When they’re not in a rush, they row in a manner similar to that of water striders. To go after prey or get away from predators, fishing spiders can speed up into a gallop.
“They sort of bounce along the water’s surface,” Robert Suter, professor emeritus of biology at Vassar College told Bates. “They take their first, second, and third pairs of legs and push down and backwards, and that wafts them into the air. They’re airborne for a few centimeters and then they land and push backwards again with the same legs.”
Fishing spiders can also sail: Taking advantage of the wind and the slipperiness of the water’s surface, the arachnids stand with two or three pairs of legs up in the air and allow the wind to catch them and propel them along the water’s surface. Suter said this might be a form of cheap locomotion for the spiders: A way to travel a long distance while expending almost no energy.
Bites “No Worse than Mild Bee Stings”
Fishing spiders are not aggressive to people and rarely bite, says Jeffrey Hahn, Assistant Extension Entomologist, on the University of Minnesota website. If they do bite, Hahn says, “it is typically because they are mishandled or feel threatened, like getting accidentally trapped under clothing.” Bites do not hurt any worse than mild bee stings, he adds. “There is no need to control fishing spiders.” The entomologist advises removing a fishing spider from a building by capturing it in a jar and releasing it outside.
National Geographic Wild Video
Fearsome Fishing Spiders
Fish Predation by Semi-Aquatic Spiders: A Global Pattern (PLOS ONE, June 18, 2014)
David Braun is director of outreach with the digital and social media team illuminating the National Geographic Society’s explorer, science, and education programs.
He edits National Geographic Voices, hosting a global discussion on issues resonating with the Society’s mission and major initiatives. Contributors include grantees and Society partners, as well as universities, foundations, interest groups, and individuals dedicated to a sustainable world. More than 50,000 readers have participated in 10,000 conversations.
Braun also directs the Society side of the Fulbright-National Geographic Digital Storytelling Fellowship.