Because the wetlands of California's Central Valley probably are noted more fortheir wintering waterfowl, mammals typically have been overlooked as an elementof these wetland ecosystems.
Mammals are an easily recognizable and definable group of animals.
Theypossess hair and, along with birds, are homeothermic, that is, having aconstant body temperature. Mammals possess avaried and complex dentition allowing them to exploit a wide array of foodresources. Being the only animals that produce milk for their young,reproduction of mammals is unique. The brain and sensory structures generallyare well developed, especially the sense of smell and hearing in some mammalgroups. Mammals are considered a very successful group of animals occurring on everycontinent and every ocean.