Biting Flies here include Horse Flies and Mosquitoes.  Horse Flies (Tabanidae) comprise about 350 species in 30 genera in North America.  Females of most species are blood feeders.  The males sip nectar at flowers and hover to attract females.  Both sexes have large eyes, but the eyes meet on top of the head on males and are separated on females.  Typically the females lay eggs in dense masses on leaves above the water.  The larvae usually live in water or wet mud and are predatory on other insects and worms.  Mosquitoes (Culicidae) are universally known as pests and disease carriers.  Only females feed on blood.  Most feed on birds and other animals.  Males have plumose antennae which aid in detecting the whine of the female's wingbeat.  The adults provide a valuable food resource for bats, birds, frogs, dragonflies and spiders.  The larvae are aquatic and are food for fish and other predatory aquatic insects.    

Snipe Flies (Rhagionidae) are represented with about 55 species in North America.  Both the larvae and adults are predatory.  The larvae live mostly in decaying wood and the adults are usually seen on foliage.