The bioassessment monitoring effort has two main field components. We collect benthic macroinvertebrates, which are bottom-dwelling animals visible to the naked eye that lack a backbone. These include creatures such as stoneflies, dragonflies, and aquatic snails. We also collect habitat measurements such as whether or not trees shade the creek to keep the water cool. This information gives us a good idea of the quality of the water and the habitat, not only for macroinvertebrates but also for the fish that feed on them.