Creepy Crawly Consumer

Last Friday was our last day of camp and we took the kids out to our pond to look for critters. Lots of great things were found and I plan to cover them in my next post. But the one that I thought was really cool was this baby. Man, was I excited to find this.

Warning: Frog-lovers Look Away, Do Not Proceed Any Further

I was chasing tiny young Blanchard's Cricket Frogs, Acris crepitans blanchardi with the kids. There were hundreds of them about and it was such fun trying to catch them by coralling them and coaxing them into a net. One was bounding along and disappeared into a clump of Soft Rush, Juncus effusus. (Note: we let all the frogs go at the end of the day.)

When I parted the rush, I found this big mama, a gianormous Six-Spotted Fishing Spider! I instantly was distracted and forgot all about the frog. How could one think of frogs with this thing around. It was huge! The kids rallied around me to check out the monster. Then I noticed that the spider was eating something... and it wasn't a bug.

It was the frog! It had captured the tiny amphibian and was having a froggy milkshake! Spiders eat by injecting venom into their prey. The venom paralyzes the victim and also digests its innards. Then they slurp the tasty beverage up like a soccer mom does an iced frappuccino from Starbucks!

I had read that Fishing Spiders will devour fish, tadpoles and frogs. Before now, I had only personally seen them eat insects. Six-Spotted Fishing Spiders, Dolomedes triton, have an amazing adaptation that allows them to float on the water. They have a waxy coating on their legs that repels water. They can float using water tension, but also have a rowing motion and a gallop that mimics the Jesus Lizards' when they need to grab prey quickly. This fascinating article explains the physics behind their bizarre locomotion. They also will hide allow the edge of the water in wait of prey. They use the element of surprise to overtake their quarry. Nature never ceases to amaze!

This post is for Watery Wednesday and ABC Wednesday. To see more posts about the letter C, go here and to see more posts involving water, go here.

Fishing Spider

As a child, and even as a young adult, I was completely wigged out by spiders. Didn't like them. Didn't want to. But a mentor of mine, Marvin Julien, who now works at The Wilds, showed me how truly amazing they were. I am ever grateful for this. I would have missed out on so many teaching moments and incredible encounters, if not for him. Now, with caution, I will even pick them up. They are fascinating and their intricate webs are architectural wonders.

Anyway, the other day, while giving a program on insects to preschoolers, we found some really cool creatures. One was this incredible, enormous Fishing Spider, most likely Dolomedes tenebrosus. A mom discovered it under a log and I pounced upon it immediately. With a little coaxing, I was able to put it in a viewing jar for all the little munchkins to see. It' s abdomen and thorax alone was about an inch in length. Add the legs and you have about three inches of spider. That is enough to send any arachnophobe into cardiac arrest!


They are fascinating creatures and are called fishing spiders because they many times are found near water. Fishing Spiders can float on the water and catch water insects and even small fish and frogs! They can easily dive under the water, if disturbed. I was surprised we found this one under a log in the woods, but discovered that this particular species is a wanderer. It will often stray far from water and be found in wooded areas, usually on trees or under logs. They are even known to eat gooey slugs. Spiders like these do not spin webs but rely on their speed to overcome and catch their prey.

With only a face a mother could love, this one has eight eyes that are located at the front of the cephalothorax. They are arranged in two rows with four eyes in each row. They have a unique structure found in a few spider groups called a tapetum. This structure is a layer of reflective cells found in the back of the spiders eye. Its function is to increase the amount of light hitting the retina of the spider's eye. This is important for spiders that do not rely on a web to catch their prey, but must rely on sight and speed. If you shine a head lamp in the forest at night, you can observe the eerie glow or eyeshine caused by the tapetum.

This video by National Geographic shows a different species of fishing spider, but you can still get an idea of how they hunt on the water. This one is catching small frogs.

http://video.nationalgeographic.com/video/player/animals/bugs-animals/spiders-and-scorpions/spider_fishing_eats_frog.html