There are some spiders that can swim and walk on water. Since spiders are so light, their thin, spindly legs do not break the surface tension of the water surface, allowing them to slide easily over the top of it.
The spiders use their ability to walk on water by floating on the surface while holding onto a structure underwater. They also have long spindly legs which help them keep their balance when they are in the water.
It should be noted, however, that these spiders cannot breathe underwater without being attached to some sort of aquatic plant or substrate because of their lack of gills. This means that they can’t last underwater for too long.
Can Spiders Swim?
There are underwater spider species that can swim and walk on water. However, they’re not too good at it. Most spiders that live in aquatic habitats, however, have the ability to walk on water using their spindly legs by making use of surface tension on the water’s surface.
Von Bibra was the first scientist to mention a spider’s ability to walk on water. He had first noticed this in 1854 and had studied it for a couple of years before he presented his findings in 1857.
It is possible that this spider was able to swim because of its web technique; since it traps prey (most likely small fish) with its web, it would be more advantageous for them to swim easier by holding onto a structure underwater as opposed to floating on the surface.
Read More: Can Spiders Eat Fish?
One thing is clear, though: spiders are not very good swimmers. They don’t have the body parts that would allow them to swim very well, so they look for other techniques when they hunt in the water.
Their best way of hunting in the water is to hold onto other structures in the water such as leaves, rocks, and sticks. With their front legs, they will wait for the prey to come in the water, after which they will pounce on the prey and eat it.
Even spiders that can’t swim still seek out water, since spiders need water to survive.
How Do Spiders Walk on Water?
Spiders walk on water by making use of surface tension. In short, spiders are so light that they can move across the surface of the water without exerting enough force to break the surface, allowing them to slide over it without sinking under.
Even some very large spiders like Wolf Spiders can swim on the surface of the water using this technique.
Most aquatic spiders that have been observed doing this have been observed hunting for prey in ponds or in small bodies of water. They usually walk on water because they’re effective predators in the aquatic ecosystem.
One particular spider is observed to walk on water when it hunts in ponds and small bodies of water: Dolomedes plantarius or the ‘water spider’. Unlike other spiders that can walk on water, however, this one uses two techniques when walking on the surface of the pond to catch its prey.
The force of the surface tension allows the spider to balance its weight on the water, which allows it to walk on water. This surface tension affects the upper layer of water, which allows the spider to grip the water with its body and walk on it with ease.
This ability to walk on water is only seen with aquatic spiders, mostly, although many other spider species that also don’t live in these areas can walk on water.
List of Spiders That Walk on Water
1. Diving Bell Spider (Argyroneta aquatica)
The diving bell spider, also known as the water spider, is a spider that lives underwater and can walk on water. It builds a web underwater and the prey becomes entangled in the web and drowns. It will then eat the dead prey.
This spider is different from most spiders because it doesn’t spin a web but instead, swims to hunt for its food. It also has two claws at the end of its legs which are used to help grip surfaces in the water.
One of their most unique features, however, are their four pairs of eyes that are usually found on spiders that live on land. These eyes are usually light-sensitive, but underwater they help them see where they’re walking or swimming in case there’s no visibility in the water.
Related Article: Are There Spiders With Wings?
2. Raft Spiders (Dolomedes fimbriatus)
Raft spiders can also be found in the water. They’re known for making a web that they drop in the water when they want to hunt in the water. They use their legs and feet to maintain balance when they hop on top of their droppings in the water.
They hunt at night when it’s dark, using their excellent night vision. They usually make a web made from strands of silk with a hole at one end, which they will drop when they want to hunt in the water from there. They can also walk on the water if they need to.
3. Six-Spotted Fishing Spider (Dolomedes triton)
Dolomedes triton is another spider species that can walk on water. They’re mostly found in the southeastern regions of the US. They spend most of their time living near bodies of water such as lakes and streams.
At night, they go down to the water and build a web on top of it. They’ll add a few strands to the web so that they can stand on it while they wait for their prey to come in through the funnel-like opening at one end of the web.
Usually, they will also wait for prey to come out of the water, as they will put their front legs on the surface of the water, while their back legs will be on a leaf or another surface that provides them with more stability.
Once the prey comes by, the spider will strike and surprise the prey. With this technique, the Six-spotted fishing spider is able to catch larger animals of prey, including some smaller fish and other species that live in the water.
MORE INCREDIBLE SPIDER ABILITIES:
- Can Spiders Walk on Water?
- Spiders that can Change Color
- Are There any Spiders with Wings?
- Do Spiders Have Spider Sense?
- Are There Flying Spiders?
Are Spiders Hydrophobic?
Some spiders are hydrophobic. Spiders’ microscopic hairs on their legs prevent the water from touching them, creating a pocket of air underwater (or under their legs) to keep the spider dry. Some research from 2009 also found that some species of spiders have a special waxy substance on their legs, which repels water at a molecular level, allowing them to float on the surface easily.
Can Spiders Breathe Underwater?
Spiders can not breathe underwater. They can’t hold their breath like humans or mammals because they have a completely different lung system. One exception is the diving bell spider, which constructs a complex aqualung with its fine silk, pulling down a bubble of air for itself from the surface, allowing it to stay underwater for extended periods.
There are some spiders that can walk on water thanks to the surface tension of the water. Most spiders that can walk on water are aquatic spiders, however, there are some species that can walk on land and water.
The one that stands out the most is the six-spotted fishing spider because it’s able to catch prey underwater while it’s blinded by its four eyes, which are known for being light-sensitive in daylight. Other spider species have been observed walking on water during their hunting expeditions.
Stuart is the editor of Fauna Facts. He edits our writers’ work as well as contributing his own content. Stuart is passionate about sustainable farming and animal welfare and has written extensively on cows and geese for the site.