An amazing find; mating stoneflies.

A female stonefly sitting on my finger.

One of the things I like to do is look under rocks and logs.  This applies not only to a woodland walk, it also applies to approachable bodies of water.  These include saltwater bodies and freshwater lakes and streams.  I am always curious about what I will find.  Many times the only treasures to be discovered are woodlice on land and mayflies in water.  As I search, patterns start to emerge.  Terrestrial salamanders can be found under wet rotting logs. Reptiles like snakes and lizards enjoy dry places that can be warmed by the sun; cardboard or plywood often is a good bet if it is in a sunny area and early in the morning.  If I want to find stonefly nymphs, I have to go to a moderately fast-moving stream that is relatively pollution-free.

I was at a park beside a very fast flowing North Thompson River a couple of days ago.  Going down to the river was out of the question because it was in flood mode and quite dangerous.  However, the banks were alive with stoneflies that had just recently emerged from the water.  I found their cast-off exoskeletons left behind attached to various plants; they crawl out of the water in nymph form and become winged adults after their last molt.  They are capable of flight after a brief period but don't typically go far.  All around me were adults that were busily trying to find a mate.

Stoneflies are not strong fliers.  I caught a couple of them and they ran quickly up my arm and down my torso trying to escape.  I admit to feeling a strong heebie-geebie response coming on but did my best to suppress any action.  Stoneflies are typically not dangerous, and besides, my buddy was watching.  I got him to hold one afterward, which in itself is a major accomplishment.  If I had succumbed to the willies I am sure he would have cringed and fled.  There is something amazing about holding life in the palm of your hand.

I saw a number of stoneflies paired up.  While single individuals might fly, there was no way a mating pair could fly.  They were intertwined to such an extent that flight would have been impossible.  However, that did not keep the pair from dodging my attempts to photograph them.  It took a while, but eventually, I succeeded.  I may do a blog on that another time.

There are quite a few species of stoneflies in BC.  They range in size and niche significantly.  The adults I caught were fairly large, about 2 inches in length from head to tail tip, but they are not the biggest ones out there.  The great thing about finding stoneflies is that it is a testament to the relative cleanliness of the water.  Given the fact that there were so many, the North Thompson must be a very clean river indeed.

Thanks for reading.   www.ericspix.com   Eric Svendsen