12 3 Wildlife Ecology

Natural Resources

Wildlife Ecology

KEYSTONE SPECIES

• A species in the environment that has a disproportionate impact relative to its abundance in the ecosystem

• Usually predators but could be a common prey species

• Example: – Prey: - Rabbits– Predator: - Wolves– Beavers: - Modify habitat

Example

• What happens when a family of beavers dams a creek?

• What habitat changes take place?

• What species can no longer survive there?

• What species might migrate in?

Wildlife Management

• Reductionist – concentrates on management and research of single populations

• Holistic – concentrates on management of the entire ecosystem

Ecological Scale

• Individual Organisms

• Populations– Group of interbreeding individuals of the same

species

• Communities– Interacting Populations of different species

• Ecosystem– Living and non-living factors in a given area

Holistic Management

• All organisms within an ecosystem are interdependent on the other organisms and species for their existence

• Example:– When wolves are present in Yellowstone

Park, the abundance and diversity of songbirds increases. Why?

Ripple Effect

• Each organism has a niche in its environment

• When the role is not fulfilled, there are repercussions & adjustments throughout the ecosystem

Yellowstone Study

• When wolves are present, moose and elk do not graze in the streams and streambanks

• When moose don’t graze on streambanks, the plant diversity and abundance increases

• When the plant diversity and abundance increases, the bird habitat is improved

• When the bird habitat is improved, the abundance and diversity of songbirds increases

Over Population Problems

• Suburban areas have severe over-population of White-tailed deer

• Nuisance to home-owners

• Danger to drivers

• Risk of disease & damage

• Hunting is not an option

Non-lethal control

• Strategy A. Identify, evaluate and use effective non-lethal deer management techniques.

• Non-lethally in suburban habitats. – Those designed to manage herd size, such as fertility

controls; – Those intended to control movement or other

behavior, such as fencing and repellents.

• Where traditional methods are not practical or desirable.

• Deer fertility control is being studied

Lethal Control

• Strategy B. Identify, evaluate and use effective lethal deer management techniques.

• Currently, lethal control is the only viable means to control deer populations on the large scale.

• Regulated hunting will remain a cornerstone of deer population control effort

• Use of sharpshooters and trap and euthanize efforts

Special Harvest Practices

• Quota Hunts – Pre-apply to hunt in areas with too many hunters for the animal population

• Managed Hunts – Hunting in usually restricted areas to reduce the population. Must pre-apply and be selected – may have to attend training

• Earn a Buck (EAB) – In over-populated counties