home range and territoriality.pptx
- 1. Presented by:Sawara Abid University Id: Bsf1907025 (Semester VII Fall 2022) ( zoology department)
- 2. Home range is the area , in which indvidual animal carries out its normal activities. Its is not defended, it is used by others as well. It is observerd that, wild animals do not roam at random and that each individual has a home region. Home ranges therefore provide a link between movements of animals and the distribution of resources that are necessary for survival and reproduction in a given area.
- 3. Home ranges are not defended, and they may overlap home ranges of other individuals of the same species . Not all portions of a home range are used on a daily basis, and use of space within the home range arises from activities including searching for or acquiring food, water, and shelter, as well as finding mates or mating opportunities.
- 4. Figure 1: Animals native to home ranges
- 5. Within the home range there is an area in which most activites are concentrated called core area. In most cases it is the area immediately surrounding the nest site or perhaps a food or water source.
- 6. Figure 2: different core area
- 7. Sizes of home ranges vary depending on multiple factors related to life-history characteristics, such as sex, body size, diet, and age class, and to environmental factors such as season, habitat structure, or availability of resources. In case of herbivore mammals, the size of the home range generally increases linearly with increasing body size.
- 8. In case of carnivores, their home range increases in size greater than their body size. While, in polygynous mammals , home range of male is larger than female Example Male southern naked tailed armadillos, the home range of male is about 2km2,while female is 0.5 km2. While in case of pigs,there is seen no difference in female and male home range.
- 9. Figure 3: Naked-tailed armadillos
- 10. A territory is an area defended against other members of the same species. It provides food, water, nesting areas and shelter from danger. Additionally, territories are smaller than home ranges, and although home ranges may overlap, territories do not. Mammals use multiple behavioral mechanisms to defend territories, including scent-marking, aggression, patrolling, and active defense.
- 12. Although singing is common in birds to establish and maintain territories. A benefit of territory defense is in exclusive access to resources in that defended area; therefore, a territory should consist of needed resources for survival and reproduction.
- 13. Males of some mammal species defend territories to acquire mates. Male arctic ground squirrels defend territories against other reproductively active males . Although females typically mate with several males, the male on whose territory she resides usually mates with her first, and paternity analysis has demonstrated that the first male to mate with an estrous female usually sires her off-spring. Males also compete with each other and the winner establish the territories . Females give birth on the selected birth sites.
- 14. Nonterritorial males, termed “floaters,” roamed over much larger areas and had somewhat overlapping home ranges. Males that switched strategies usually began as floaters; then, as they reached maturity with increased body mass they switched to territorial behavior.
- 15. A mating system involving a peculiar type of territory is the lek. Female choice is an important aspect of lek- breeding species, because females move through the area and choose the males with which they mate. While on the lek, the males do little or no feeding; they spend all their time and energy patrolling the boundaries, displaying to other males, and attempting to attract females into their area .
- 16. The factors that influence the lek in which females choose to mate are not clear, but females typically prefer dominant males that are centrally located in the breeding areas .