Biotic Sampling

Question 1

Capture Mark Recapture

Answer 1

The size of invertebrates or mammals in an area can be estimated using capture-mark-recapture. Useful for invertebrates with shells, such as snails and limpets or invertebrates with exoskeletons such as woodlice.

Question 2

Capture Mark Recapture technique

Answer 2

A sample of animals is captured and marked in some way. These are then released and allowed to re-mix with the population. A second sample is taken later. The population can be estimated fro, the proportion of marked animals in the second sample.

Question 3

Sampling Traps

Answer 3

Mammals:
The Longworth small mammal trap works by enticing small mammals into a rectangular tube using food as bait; when the door is sprung it closes behind the mammal.

Question 4

Sampling Traps 2.

Answer 4

Moths:
Most moth traps consist of a light to attract the moths and a box in which the moths can accumulate and be examined later. The moths fly towards the light and spiral down towards the source of the light and are deflected into the box.

Question 5

Invasive Sampling

Answer 5

Capture-mark-recapture is an example of invasive sampling as the animals are handled by scientists.

Question 6

Non Invasive Sampling

Answer 6

If possible, scientists carry out non-invasive sampling. For example monitoring footprints.

Question 7

Pitfall Traps

Answer 7

This is used to sample small moving invertebrate species that live in the soil surface and leaf litter, For example beetles, spiders or woodlice.

Question 8

Tree Beating

Answer 8

Tree beating is used to sample small organisms that live in the branches and leaves of trees. It requires a stick and a white sheet or tray to catch the falling organisms.

Question 9

Tullgren Funnel

Answer 9

The Tullgren funnel is used to extract invertebrates from samples of soil or leaf litter brought back from the woodland to the lab.

Question 10

Baermann Funnel

Answer 10

The Baermenn funnel is a similar sampling technique - used to extract nematodes (worms) from a soil sample or plant material.