investigating populations

Question 1

basics

Answer 1

1. choose area to sample
2. samples should be random to avoid bias
3. use appropriate technique
4. repeat process (reduce likelihood results due to chance
5. number of individuals for whole are can be estimated by taking mean

Question 2

non motile organisms

quadrat

Answer 2

1. % cover - counting how much of quadrat is covered (if it is more than half in a square = quick

Question 3

non motile organisms

transects

Answer 3

1. find how things are distributed
2. belt transect - quadrats placed next to eachother along a transect
3. interrupted belt transect - place quadrats at intervals

Question 4

motile organisms

mark release recapture

Answer 4

1. capture using appropriate technique
2. mark them harmless way
3. release
4. wait a week and take 2nd sample - count how many marked
   1st sample x 2nd sample / number marked in 2nd sample

Question 5

assumptions for mark release and recapture

Answer 5

1. marked sample has had enough time and oppotunity to mix back
2. the marking hasnt affected chance of survival
3. no changein population size due to births, deaths and migration