Why manage disturbance?
What is disturbance?
Disturbances occur when animals respond to the presence of potential threats. These threats can disturb any normal behaviour of animals, such as feeding, resting or breeding. A diverse range of stimuli can disturb animals. Natural disturbances include potential predators. Human-related disturbances include the mere presence of humans, vehicular traffic and anthropogenic noise.
Why measure disturbance?
Intense human disturbance to birds has already lead to population declines in Australia’s birds, such as our beach-nesting birds. One key issue facing land managers is how to balance the increasing demand on public open space for humans (e.g. recreation) with the needs of the biodiversity which inhabit those areas. Animal fear responses also have an animal welfare dimension, because at the individual animal level, excessive fear is likely to compromise the wellbeing of affected animals. Understanding how animals fear humans can enable us to put measures into place to reduce our disturbance to wildlife.
How is disturbance measured?
The degree to which animals fear humans can be estimated by the distance at which the animal begins to escape an approaching human. This is known as their flight-initiation distance (FID). FIDs have been collected from hundreds of Australian bird species, which form the basis of this online resource.
The majority of FIDs have been collected from birds responding to the approach of single walkers. This information can be used to assess the disturbance caused by, for example, recreationalists on birds. However, many other stimuli can also disturb birds. The online resource therefore also contains information on FIDs of various bird species in response to other stimuli, such as cars, buses, groups of three walkers, a walker with a leashed dog, joggers and people in canoes.
The distance at which people start approaching birds (their starting distance) is known to be related to FIDs. When people start approaching an individual bird at a greater distance, then the bird’s FID will also be longer. The starting distances of FIDs used in this online resource were therefore collected at a range of starting distances to reflect the variable distances at which birds will first detect human-related stimuli in their habitat.
More information on human disturbance to Australian birds can be found here, while a video outlining more detail on how FID data is collected can be seen below.