Bio 14.4 Sampling techniques

Question 1

What is aerial sampling?

Answer 1

This is a method of counting animals that assesses the abundance of large species of the African continent. This estimates the number of animals in a small part o the survey area.

Question 2

What are pitfall traps?

Answer 2

These are traps that trap small invertebrates living on the ground.

Question 3

Why must pitfall traps be covered?

Answer 3

• To keep out the rain
• To make it dark
• To prevent birds from eating the catch

Question 4

Why is it important to have a large number of pitfall traps placed in random locations?

Answer 4

• Makes results more reliable

- Minimises the effect of unusual results

Question 5

What is the formula for estimating population size using the mark-and-recapture method?

Answer 5

1st sample * 2nd sample
_________________________
2nd sample previously marked

Question 6

How do you estimate the number of plants in a given area, using a quadrat?

Answer 6

• Measure the total area in m^2
• Throw quadrat in a random location
• Count the number of plants in it
• Place the quadrat in different places and take an average count of no. of plants.
• Multiply the number of plants by the total area

Question 7

Why should a quadrat be placed randomly?

Answer 7

• So that a representative sample is taken

- For better validity and reliability