Additional Science | B4, C4, P4 | OCR Gateway

Biology

Methods od Sampling

Pooter -

A simple technique where insects are gathered up without any pain being inflicted.

Works for insects only!

Aim for the insect to be ****ed into one straw whilst you **** through the straw thats covered with a fine mesh to stop you from ****ing up tge unsects into you mouth. 

This is a systamatic method and its difficult to get ideas of numbers using it.

Sweepnet -

Sweep nets are self explainitory. 

Normally used for insects.

Again, it's hard to get an ideas of numbers using this method of sampling.

Pit Fall Trap -

Pitfall traps are set into the ground. They are normally used to capture small insects like ants and beetles. A chemical like ethanol can be put into the bottom to kill any insects that ownder in there, however this is ethically wrong. 

Works well with animals and insects!

This method can give a good indication of how many of a species there are in an area.

Quadrat - 

Quadrata are square frams that can be placed in different environments. In this case grass^.

Works for insects only!

They normall have four even lengths of 0.5 metres and provide good results for sampling as long as they are placed randomly. 

Lincoln Index Sampling

There is a more effectve way of sampling to get a more accurate number for species populations.

Here is the method:

1: Catch animals (Sample 1)

2:Mark them - For exanple Water Boatmen, a type of insects, are marked with a waterproof pain that do not harm them in any way, shape or form.

3: Release the marked animals

4: Catch another sample (Sample 2) - Some will already be marked and some will be unmarked.

The following equation can be done to get an estimate on the total population size in the habitat.

Population Size= Number in 1st Sample X Number in…