The five-minute bird count (5MBC) method is generally used for forest birds.

5MBCs are relatively easy to do and require few resources. Other methods such as mark-resight and distance sampling can, however, give much better estimates of bird numbers.

Five-minute bird count studies have been used to:

• Argue for the protection of forests e.g. In the 1980s they helped demonstrate the importance of West Coast and Central North Island forests when they were at threat from logging.
• Monitor progress in ecological restoration projects e.g. the Rotoiti Nature Recovery Project, St Arnaud Mainland Island.
• Monitor changes in bird populations over time e.g. whether New Zealand pigeon/kereru in Northland forests decreased over time and whether pest control helped stop the decline.
• Investigate whether birds use different types of forest in different seasons. This understanding helped design reserves and wildlife corridors in the 1980s e.g. the North Westland Wildlife Corridor between the Paparoas and the Southern Alps.
• Identify sites of special wildlife interest e.g. Southland’s reserve network.

The 5MBC method is an index measure. Rather than measuring the actual density or abundance of birds directly, it records some of the individuals present and uses this measure to infer density or abundance.

For five-minute bird counts the relationship between the number recorded and the real density or abundance is usually unknown and probably changes with time of day, season, etc.

Do a five-minute bird count