Unit 2 - Topic 1 - Field techniques for Biologists - Section D - Monitoring Populations

Question 1

What can the presence, absence or abundance of a indicator species give information about

Answer 1

Environmental qualities, such as presence of a pollutant

Question 2

What species can be used to monitor ecosystems

Answer 2

Susceptible and favoured specices

Question 3

How do susceptible and favoured species indicate ecosystem health

Answer 3

Absence or reduced population indicates a species is susceptible to some factor in the environment. Abundance or increased population indicates it is favoured by the conditions

Question 4

What is the procedure for the mark and recapture technique as a method for estimating population size using formula

Answer 4

N=MC/R M=original marked, C=second capture total, R=recaptured

Question 5

What is assumed about the mark and recapture method

Answer 5

All individuals have an equal chance of capture, that there is no immigration or emigration, and that individuals that are marked and released can mix fully and randomly with the total population.

Question 6

Name methods for marking animals and what must be assured in doing this

Answer 6

Banding, tagging, surgical implantation, painting and hair clipping. Method must minimise the impact on the study species