Kingfishers are small plump birds (approximately 6.5 inches) with a small tail, large head and a long sharp bill; their beautiful iridescent blue backs and tails, orange-red underparts and white throats make them unmistakable. Males and females are similar but the female can be distinguished by the red on their lower bill; young birds are duller and greener than adults. They are birds of slow moving or still water catching their main prey of freshwater fish by perching over the water and then diving to catch small fish as they swim by. Other prey include aquatic insects, small amphibians and occasionally crustaceans. They fly fast and low over water and often the the first and last thing you see of a nearby Kingfisher is a flash of blue as it hurtles past you. In winter, especially hard ones, some Kingfishers will move to estuaries and coastal areas.