|
Habitat
All animals need food to meet their energy needs: to grow, reproduce, escape predators and survive chilling winters or long migrations. Each species selects particular foods from many items that are present in its environment. Not just any kind of food will do. For a bighorn sheep to survive, for example, there must be enough grass to last throughout the winter, and the grass must also have sufficient nutritional value. The quality of food, as well as the amount present, is important for survival. Food quality may vary with the season, or even the location. Food must also be accessible to the animals. In winter, deep, crusted snows may bury much of the food supply. An important objective for wildlife management is to conserve important feeding areas, and to increase the amount and quality of food available for wildlife. Winter food shortage is the most important limiting factor for many wildlife species. Shelter Birds and mammals need shelter or cover to hide in, and to protect them from bad weather. Dense vegetation is the most common kind of cover, but cover may also include rock piles, burrows in the ground, holes in logs or water bodies. Some small animals, like beaver and muskrats, build their own cover in the form of houses. Plant cover is removed by many modern land uses like logging, cattle grazing and open pit mining. Water Like humans, all animals need water to survive. Many of our wildlife species get enough water from the food they eat, such as succulent plants, but some also need to drink water, particularly in dry regions. Space Animals need space to survive. Overcrowding leads to severe competition for food and breeding sites and eventually to malnutrition and rapid spread of disease and parasites. Most animals are territorial to some extent; that is, they will occupy specific sites and keep other animals out. Their territoriality tends to ensure spacing and prevent overcrowding. Because of the need for space, a given area will only support so many animals, no matter how much food, water or shelter they receive. Many wildlife species have very particular needs for breeding sites. Dense forest cover is needed by cow elk to conceal their newborn calves and by tree-nesting birds to hide their nests. Bald eagles need large old trees to support their bulky nests, and these trees must be near the shorelines where they feed. Hole-nesting birds need snags and old trees in which to excavate nests, falcons need cliff ledges and seabirds that nest in colonies need secluded islands. Some mammals, like wolves and bears, need particular soil conditions for digging their maternity dens. Wildlife managers try to protect breeding sites, and to improve them where possible. Arrangement Wildlife species must have access to food, water, cover and space. If one of these components is removed from the habitat, the animal cannot survive. Measuring Habitat |
Food