Data analysis and interpretation

Data analysis and interpretation for presence / absence surveys  

Since the objective of this method is to determine a species presence or absence then only limited analysis can be done. This method is primarily used to make sure a species is still persisting at site and little else.

The presence or absence of individual populations being searched across a large area during one survey can be used to determine overall change in condition of a species. That is, if a species has been recorded at 10 sites, then 9 in the following year and then 6 and so on, then a species decline may be inferred. This information can be converted into numerical data such as a count per unit of time or density within a searched area (as an index of population size or condition).

This page last updated on 23 Sep 2012