Measuring behaviour - Chapter 6 & 7

Ethogram

• A written inventory of behaviours in a species’ repertoire

• Can be partial or complete depending on the research question

• Should be based on pilot observations

Classifying behaviours in an ethogram

• Descriptive/Structural: “Nose is pressed or close to the ground (less than 10 cm) with jaw muscles moving”

  • Can sometimes be too exclusive and detailed

• Functional: “Feeding”

  • Can sometimes be too broad

Behavioural categories for an ethogram*

• Mutually exclusive

• Objective

• Reliably measurable

• 
  

Events

• Classification of behaviours

• Relatively short duration

• Typically low variance in duration

• Usually measured in frequency of occurrences

Common pitfalls when making an ethogram*

• Anthropomorphism

• Categories that are too broad

• Categories that are too narrow

• Overlap between categories

Types of measurements for behaviours:*

• Latency

• Frequency

  • The number of occurrences of the behaviour per unit of time/per total observation time

  • Suitable for event behaviours

• Duration

  • 
    

• Intensity

  • 
    

When observing a group of animals: *

• Crucial to be able to assign the behaviours to specific individuals

Sampling rules

Which subject/s should we watch and when

Four types:

• Ad libitum sampling

• Focal sampling

• Scan sampling

• Behaviour sampling

Recording rules*

Two types:

• Continuous recording

• Time sampling

Ad libitum sampling*

Focal sampling*

Scan sampling*

Behaviour sampling*

Sampling types for watching groups*

Socio-metric matrix*

Continuous recording*

Bout

When event behaviours are repeated many times

Time sampling*

a

Two types:

• 
  

~Interval sampling*

1/0 sampling*

How to assure reliability in behaviour studies:*

States

• Classification of behavioural categories

• Relatively long duration

• Typically higher variance in duration

• Usually measured in duration