Research methods

Question 1

Why do we sample population sizes?

Answer 1

difficult to measure total size

cheaper

quicker

Question 2

What is systematic sampling?

Answer 2

Using intervals when sampling

Question 3

What is stratified sampling?

Answer 3

Dividing data into sub groups to ensure all data is collected fairly

Question 4

What is a quadrat used for?

Answer 4

To study populations

Question 5

What are nets used for?

Answer 5

To catch a variety of different aquatic organisms

Question 6

Limitation of nets?

Answer 6

Mobile species may escape

Question 7

What is kick sampling?

Answer 7

Used to collect aquatic invertebrates from river bed

net is positioned on bed of the stream, face open to the current

then kick the sediment and organisms flow into net

Question 8

How do you get fair results with kick sampling?

Answer 8

control the number and length of kicks

Question 9

What is a Surber sampler?

Answer 9

Box-like frame used to collect aquatic organisms

Question 10

Limitations of Surber sampler?

Answer 10

Cannot work on uneven river beds

Can only be used where water flow is fast enough to carry organisms into net

Question 11

How and what is a plankton net used for?

Answer 11

Fixed where there is a current or towed

Used to collect planktonic organisms

Question 12

Explain the process of using a pooter (suction sampler?)

Answer 12

Use a jar with a lid through which
there are two tubes.

You place one tube quickly over
the animal and then suck through
the other gauze-covered tube, this
draws the animal to the jar

Question 13

What organisms is a pooter (suction sampler) used to collect?

Answer 13

Used to collect organisms from
tree bark and litter

Question 14

What are motor driven suction samplers used for?

Answer 14

Air suction samplers capture flying insects.

You can measure the number of insects
per unit volume of air and ALSO ground vegetation

Question 15

What is a sweep net used for?

Answer 15

To collect organisms on the ground then the net can be turned out into a large white tray for identification

Question 16

How can you ensure a fair test with a sweep net?

Answer 16

Same number and length net should be used

Question 17

What is a beating tray and what is it used for?

Answer 17

A sheet or tray is placed beneath vegetation
which is beaten several times with a stick.

The invertebrates are dislodged and fall
onto the sheet, then collected for
identification and counting.

Question 18

What is a pitfall trap?

Answer 18

A jar sunk into the ground

The trap need to be covered to
keep out rain and predators

A preservative fluid may be used to
kill captured animals for later
study

This can be left for several hours or
overnight

Question 19

Why are light traps not always fair tests?

Answer 19

Because different species are attracted to different types of light and wavelength

Question 20

What is colonisation media?

Answer 20

Where some species are monitored by providing suitable habitats that they may colonise

Question 21

Definition of a Tullgren funnel?

Answer 21

A Tullgren funnel uses heat and light to drive organisms out of a soil or leaf litter sample and into a collecting container

Question 22

Explain the process of using a Tullgren funnel?

Answer 22

Soil or leaf litter sample collected

Place funnel under light source

Heat and light dry up sample from top to bottom

Organisms then move downward to escape heat and fall into collecting jar

Question 23

List some specialist techniques for ecological research?

Answer 23

Imagery
Marking
DNA databases
Auditory
Position monitoring
Sensor carrier systems

Question 24

List examples of indirect monitoring?

Answer 24

footmarks

droppings

nest

feeding marks

Question 25

What are image data bases?

Answer 25

where unique features are recorded in a database eg. tiger facial stripes

Question 26

Limitations of imagery?

Answer 26

Few species have unique features that could be used for identification

Question 27

What is the Chi-squared test used to see?

Answer 27

if the difference between observed and expected frequencies is significant — or just due to chance