The insects studied have mostly been butterflies and moths, bees, beetles, dragonflies, damselflies and stoneflies. Some of the insects most affected include bees, butterflies, moths, beetles, dragonflies and damselflies. Several species of Odonata (dragonflies and damselflies) and other invertebrates have also been recorded. The Odonata are an order of flying insects that includes the dragonflies and damselflies. Dragonflies and damselflies are predatory both in the aquatic nymphal and adult stages. Dragonflies are agile fliers, while damselflies have a weaker, fluttery flight. Dragonflies and damselflies have fore and hind wings similar in shape and size. There are 15 species of threatened damselflies and dragonflies in Michigan. Although generally fairly similar, dragonflies differ from damselflies in several, easily recognizable traits. Dragonflies are more affected by pollution than are damselflies. The Chao Phraya basin is home to about half a dozen endemic dragonflies and damselflies. Additional viruses from this group have been reported from dragonflies and damselflies. The major predators are birds, but wasps and damselflies also prey upon smaller juveniles. All damselflies are predatory; both nymphs and adults eat other insects. Adult damselflies catch and eat flies, mosquitoes, and other small insects.