The duck-billed platypus (Ornithorhynchus anatinus) is an aquatic monotreme distributed along the east coast of mainland Australia and in Tasmania. It lives in burrows dug near rivers and lakes; its bill contains numerous electroreceptors and it forages by sifting through gravel to find small fish, crustaceans, and insect larvae. It swims using webbed forefeet and folds them when walking on land. The female lays eggs and, since there are no nipples, milk is secreted onto the body surface. The male has spurs capable of delivering venom during the breeding season. Populations are in decline due to habitat degradation, and the IUCN classifies the species as Near Threatened.