Patagonian Desert albeit to the west, where precipitation is higher, bushes are replaced by grasses. Topographically the deserts consist of alternating tablelands and massifs dissected by river valleys and canyons. The more western parts of the steppe host lakes of glacial origin and grades into barren mountains or cold temperate forests along valleys. Inhabited by hunter-gatherers since Pre-Hispanic times, the desert faced migration in the 19th century of Mapuches, Chileans, Argentines, Welsh, and other European peoples, transforming it from a conflictive borderland zone to an integral part of Argentina, with cattle, sheep and horse husbandry being the primary land uses. The Patagonian
Patagonian crested duck female, and takes about 30 days, following which the eggs hatch synchronously. Once hatched both parents tend to the ducklings. They fledge at about 10–11 weeks old. The duck eats aquatic invertebrates such as insects and their larvae, crustaceans and molluscs. It also eats small amounts of aquatic plants such as the filamentous algae common in many ponds. The diet for the young is much the same as their parents. To get their food the ducks dive for algae and invertebrates at the bottom of waterbodies. Diet varies between fresh and salt water habitats, as well as seasonally. The Patagonian