Wildlife Management
EVPP 111 Lecture
Danielle Derwin
March 19, 2003
What do we mean by Wildlife Management?
Before we look at what wildlife management is, we need to define what we consider wildlife.
Wildlife Definition
What do you think?
It is a hard word to define, depends on whom you talk to.
Just terrestrial?
It designates free-ranging birds and mammals
Wildlife Management
The way I define wildlife management is as the management of wildlife populations.
Biological Diversity
Must know about the animal and their habitat to attain these goals.
No habitat, no animals.
Why manage wildlife?
In the face of expanding human numbers and activities, most such wild living resources have been or are being depleted.
Originally, most management was only on a single-species level with no account of the ecosystem.
We need to start thinking at an ecosystem level
Manipulative vs. Custodial
WM may be either one.
- Manipulative management does something to a population wither changing its numbers by direct means or influencing numbers by the indirect means of altering food supply, habitat, density of predators, or prevalence of disease.
Manipulative vs. Custodial
Custodial management on the other hand is preventative or protective.
It is aimed at minimizing external influence on the population and its habitat.
Allows free rein to the ecological processes that determine the dynamics of the system.
Still… even with management, species may go extinct
Why do we try to save endangered species?
Some possible reasons:
Ecological?
Cultural?
Moral?
Biodiversity?
Four Causes of Extinction
Population Risk: Random variables in population rates can cause a species in low abundance to become extinct.
Environmental Risk: Variation in the physical or biological environment, including variations in predator, prey, symbiotic, or competitor species.
Four Causes of Extinction
Natural Catastrophe: Fires, major storms, earthquakes, flood.
Genetic Risk: Detrimental change in genetic characteristics not caused by external environmental changes; reduced genetic variation, genetic drift, and mutations can be cause these changes in a small population.
Traits of Endangered Species
Long lived
Larger species need larger territories and more food .
Large species with low reproductive rates are easily endangered and recover slowly from lowered population levels.
Let’s review reproductive rates!
R vs K selected species
R SELECTED
- Many small offspring
- Little/no parental care
- Most offspring die before repro age
- High pop growth rate
- Early succession species
R vs K selected species
K SELECTED
- Fewer, larger offspring
- High parental care
- Later repro age
- Most offspring survive to repro age
- Lower pop growth
- Late succession species
Survivorship Curves
Biological Diversity
What do you think is biological diversity? At what level are we considering?
Involves three concepts.
Genetic Diversity
Habitat Diversity
Species Diversity
Types of Genetic Diversity
Loss of genetic diversity = loss of adaptability
For natural selection to occur it needs:
Genetic variation for some trait. Examples: color pattern, fleetness, enzyme metabolism.
Without genetic variation, populations can not adapt to a changing environment.
With a changing env’t a variation might enable some ind to be better adapted to changes than others.
Moths in England
One type of adaptation: camouflage.
Before 1800s and industrial rev, black moths were rare while the white variety hid on the lichens.
After 1800s, lichens died, then black variety increased.
Inbreeding
Habitat Diversity
When habitats are destroyed the species that live in that habitat will be decimated or displaced.
Habitat Diversity effects Genetic Diversity
Genetic Diversity increases when:
there is a physically diverse habitat
Genetic Diversity Decreases when:
under extreme stress
Extreme env’t (at extreme of tolerance for living things)
Geographic isolation
Adaptive Radiation
Species Diversity
Some species have evolved around each other (niche partitioning).
Therefore without all the species represented, some species may suffer.
Food prevalence
Predator/Prey interactions
Species on the Serengeti
Catena
Wolf & Moose: Isle Royale
Isle Royale in Lake Superior, 1948 a pair of wolves came to the island.
An examination of the populations suggest that they have an effect on one another.
Wolf & Moose: Isle Royale
How can we preserve biological diversity?
In order to save some species from extinction we need to create captive populations.
Would like about 1000 founders, but usually get much less.
California Condors: 14
Speke’s Gazelle: 4
Black-footed ferrets: 7
How can we preserve biological diversity?
Why do we want to have as many founders as possible for a captive population?
RIGHT! Genetics!!!
If we have the last few remaining species ...
Then we need to make due with what genetics we have.
Look at mean kinship before breeding.
The average kinship between an ind and all the ind in the population (including itself)
If there are still more in the wild...
Go get some more genes!
Genome research bank (GRB)
How to obtain some genetics
Electroejaculation
Look what I do for you students!!
Can be brought out into the field
Not applicable for all species.
What about the habitat?
We need to conserve the habitat as much as we need to conserve the species.
Without habitat, how can we reintroduce the species?
Tracking animals
We can use radio collars to track animals and determine their homerange.
What is an animals homerange?
Catching Animals
Once animals are tagged, need to track them.
To track collared animals we use radiotelemtry to pin point their location.
Using GIS to determine homerange
Once the points have been determined, we can plug the info into GIS and determine the animals homerange.
After homerange is determined
Then we can figure out what areas we need to protect.
Very hard to protect an ecosystem.
Usually use a poster child species that in turn protects the ecosystem it resides in.
Northern Spotted Owl
What about migrating species?
How do we determine their homerange?
Should all of the homerange be protected?
Wildebeest in Serengeti.
Migratory Birds
Migratory Birds
Migratory birds make north-south journeys from one habitat to another each year.
Flyways.
Therefore, all the habitats used by these birds need to be protected if the species is to survive.
Swanson Hawks.
Discussion Questions
Discuss your gut-level reaction to the following statement: "Eventually all species become extinct. Thus, it is does not really matter that some species went extinct, and some are endangered mostly because of human activities"
Be honest!
Discussion Questions
Do you accept the ethical position that each species has the inherent right to survive without human interference, regardless of whether it serves any useful purpose to humans?
Would you extend this to species that cause disease in humans?
Discussion Questions
If the only population of a species is in a zoo, and there is no chance of ever reintroducing the species back into the wild because their habitat is completely destroyed, should we use resources to fund further reproduction of this species?