Estimating Population Size Flashcards
1
Q
What do direct methods involve?
A
- counting every single individual in a population - this is called a census
2
Q
What are the types of methods used to estimate population size?
A
- direct methods
- indirect methods
3
Q
When can direct methods be used?
A
- for populations where organisms are large enough to be seen
- where the area in which the animals are being counted is not too large
4
Q
For what kind of individuals can direct methods be used?
A
- slow moving (e.g.
- stationary (e.g. plants)
- usually stay in a fixed position (e.g. barnacles)
5
Q
What can be used if the area is too large to count every individual at one time?
A
- aerial photographs can be used to show the whole area in which the population occurs
- helicopters can be used to count larger animals
6
Q
What do indirect methods involve?
A
- counting a sample number of the population and then using simple calculations to estimate the total size of the population
7
Q
What are some examples of indirect methods?
A
- quadrat method
- mark-recapture method
