Lake Water Quality - Mosquito

Unlike the daphnia in the earlier photograph, these aquatic invertebrates do bite and annoy humans--once they grow up: these are mosquito larvae.  If you have standing water in your back yard (such as might be found in an old tire, a poorly-drained burn barrel, or a neglected bird bath), look for these guys. They will be hanging upside down from the surface film and will scatter when you wave your hand over them.