I fish a number of lakes here in Colorado. Recently I did a stomach pump of a fish and found him stocked full of tiny little round insects less then the size of a BB. They could swim very fast and darted in all different directions, the colorations were from light tan to dark brown. It seemed like the bigger ones were darker in color. Does anyone have any ideas of what these things are? The lake is about 1mile around deepest is 30 feet and its the time of year where large beds of weeds extend up from the bottom. I caught this fish amongst the heavy vegetation in about 12 feet of water. Any ideas?
They may have been Predaceous Diving Beetle adults. Here is one of genus Oreodytes from the S. Fork Snoqualmie: It is only 2.2 mm, which is about as small of an adult as you will find, but some other genera have much larger adults. And yes, they swim incredibly fast with those two hind legs, which are lined with swimming hairs.
That may be them. Are they round? these things were as tall as they were long... almost like little swimming balls. Thanks
Am not aware of any aquatic insects which could be accurately described as "almost like little swimming balls." I would need to see a macro photo of this creature in order to identify it for you.
No pictures to show. That is the closest looking beetle I have seen. I figured these insects may have been the hatchlings of a larger insect but the water in the area must have been full of them. Thanks Taxon
