Like most of southern California, the majority of San Diego's current area was originally occupied by chaparral, a plant community made up mostly of drought-resistant shrubs. The endangered Torrey Pine has the bulk of its population in San Diego in a stretch of protected chapparral along the coast. The steep and varied topography, and proximity to the ocean creates a number of different habitats within the city limits, including tidal marsh and canyons. The influence of humans has altered existing habitats and has also created habitats that did not exist prior to human development, by construction of buildings, the introduction of new species, and the use of water for lawns and gardens. A number of species of parrots, including the Red-masked Parakeet and Red-crowned Amazon have establishe