calculating biodiversity

Question 1

what are techniques used to collect animals

Answer 1

-sweep nets
-tree beating
-pooter
-pitfall trap
-kick smapling

Question 2

explain capture mark recapture

Answer 2

• Organisms are captured using an appropriate technique (pitfall traps, sticky traps, etc)
• Captured organisms are marked with non-toxic waterproof paint
• Marked organisms are released back into the environment
• After a suitable period of time, the population is sampled again
• The number of marked and unmarked organisms in the second sample is recorded

Question 3

what assumptions are made when estimating population size

Answer 3

• Marking should not disadvantage individuals in any way, e.g. making organisms more visible to predators
• Marked individuals are assumed to mix completely back into the original population
• There should be no immigration or emigration of individuals between sampling periods, i.e. the population is closed
• It is assumed that there are no births or deaths during the period of the study

Question 4

what is the equation for estimating population size

Answer 4

Population size (P) =
number of organisms in first sample x number of organisms in second sample ——————————————————
number of marked individuals captured
in second sample