Why do mosquitoes bite? It’s only the female mosquitoes that bite and they bite because they need your blood. Male mosquitoes mostly feed on plant sugars. Almost all types of mosquitoes bite because they need blood. Blood provides a great energy hit to help them develop eggs. Mosquitoes don’t just bite people. They will feed on the blood of many different animals. This includes birds, mammals, lizards, snakes, frogs, and even fish! (Fish-feeding mosquitoes is a story for another time) Mosquitoes