2.1 Field Techniques

Hazards in field work

Adverse weather conditions, difficult terrain, problems associated with isolation, and contact with harmful organisms.

Risk

The likelihood of harm arising from exposure to a hazard.

Risk assessment

Identifying control measures to minimise risk

Control measures in field work.

Appropriate equipment, clothing, footwear, and means of communication.

Considerations of sampling

It should be carried out in a manner that minimises impact on wild species and habitats. Consideration must be given to rare and vulnerable species and habitats that are protected by legislation.

Point count

Involves the observer recording all individuals seen from a fixed point count location. This can be compared to other locations or with data from the same location gathered at other times.

Quadrats

Suitable size and shape, or transects are used for plants and other sessile or slow-moving organisms.

Capture techniques for mobile species

Traps and nets

Camera traps

**Direct** method for sampling elusive species

Scat sampling

**Indirect** method for sampling elusive species

Identification of an organism

Classification guides, biological keys,or analysis of DNA or protein.

Taxonomy

The identification and naming of organisms and their classification into groups based on shared characteristics. Based on morphology

Phylogenetics

The study of the evolutionary history and relationships among individuals or groups of organisms. It uses heritable traits such as morphology, DNA sequences, and protein structure to make inferences about an organism's evolutionary history and create a phylogeny

Examples of taxonomic groups

Nematodes, arthropods and chordates

Model organism

Those that are either easily studied or have been well studied. Information obtained from them can be applied to other species that are more difficult to study directly.

Monitoring populations

Presence, absence or abundance of indicator species can give information of environmental qualities, such as presence of a pollutant

Susceptible and favoured species

Absence or reduced population indicates a species is susceptible to some factor in the environment. Abundance or increased population indicates it is favoured by the conditions

Mark and recapture

A sample of the population is captured and marked (M) and released. After an interval of time, a second sample is captured (C). If some of the individuals in this second sample are recaptured (R), then the total population can be worked out using N = MC/R

Assumptions for mark and recapture

All individuals have an equal chance of capture, that there is no immigration or emigration, and that individuals that are marked and released can mix fully and randomly with the total population.

Methods of marking animals

Banding, tagging, surgical implantation, painting and hair clipping The method of marking and subsequent observation must minimise the impact on the study species

Measurements used to quantify animal behaviour

Latency is the time between the stimulus occurring and the response behaviour. Frequency is the number of times a behaviour occurs within the observation period. Duration is the length of time each behaviour occurs during the observation period.

Ethograms

Lists species-specific behaviours to be observed and recorded in the study. Recording the duration of each of the behaviours in the ethogram, together with the total time of observation, allows the proportion of time spent on each behaviour to be calculated in the time budget.

Anthropomorphism

Can lead to invalid conclusions by imposing human behaviours on animals.