Monitoring Populations Flashcards
What can give information of environmental qualities such as presence of a pollutant?
Presence, abundance or absence of indicator species
What can be used to monitor an ecosystem?
Susceptible and favoured species
What can an absence or reduced population indicate?
That a species is susceptible to some factor in the environment.
What can abundance or increased population indicate?
That a species is favoured by the conditions
What is mark and recapture?
A technique that is a method for estimating population size
How is estimating a population size calculated using the mark and recapture technique?
By using the formula N=(MxC)/R
A sample of the population is captured and marked (M) and released. After an interval of time a second sample is captured (C). If some of the individuals in this second sample are recaptured (R) then the total population (N) can be calculated using the formula
What does the mark and recapture technique method assumes?
That 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.
What do methods of marking animals include?
-banding
-tagging
-painting
-hair clipping
-surgical implantation
What must the method of marking and subsequent observation do?
Minimise the impact on the study species
