Draft National Wind Farm Development Guidelines - July 2010

D.4.3 Planning Application
The following tasks are likely requirements of any assessment process.
Quantitative assessment of risk of fatal collisions for key species
If preliminary assessments outlined in previous phases determine there is potential for
mortalities of key species resulting from interactions with turbines, then investigation to
quantify this risk will be required as follows.
Principal question:
Purpose:
Methods:
What is the quantitative risk to key species of collision mortalities
To quantify the inherent risk to key species of the wind farm as proposed.
For this stage, the studies will include:
• qualitative
Geographic Information Systems – habitat models
behavioural studies
• quantitative
population surveys
collection of data for estimation of annual number of flights at risk of
collision
collision risk modelling to predict potential mortalities
The definition of exactly which species are “key species” will need to be confirmed by the
relevant authorities before this task can be finalised.
Habitat modelling, mapping of territories and/or mapping activity patterns of key species
at the site should be undertaken to gain insight into whether parts of the site pose greater
risk of collision than others. Results may have application in design of a turbine layout to
avoid or reduce impacts. (see also Assessment of any reduction or mitigation of impacts
that can be achieved, page 128).
Risk modelling approaches can range from the use of sophisticated mathematical models
to qualitative evaluation and the approach used will depend on the availability of
information. Collision modelling is the preferred method of assessing risk and is likely to be
required by the relevant authorities when sufficient information is obtainable.
When a numerical assessment of potential impact on particular species is undertaken, the
appropriate approach will be use of a peer-reviewed mathematical risk model. A number
of such models are in use internationally. This type of collision risk modelling is a predictive
mechanism used to quantify the potential annual number of flights made by key species
that are at risk of collision and may result in bird or bat mortalities. Inputs required to
undertake such modelling include standardised bird or bat utilisation data (quantified as
outlined below); number and geographic layout of turbines; and dimensions and other
parameters of turbines. Pre-requisites for an outcome measured in terms of an expected
annual number of mortalities, are both the number of individuals that might interact with
turbines and the estimated number of their flights that are at risk of collision.
The ultimate justification of any mathematical model is how well its predictions are verified
by measured outcomes. To date there are no examples of Australian wind farms where
both pre-construction bird utilisation studies and post-construction mortality monitoring
have been undertaken sufficiently rigorously to confirm the accuracy of the relevant
collision risk model with a high degree of confidence. In the absence of such verification,
the predictions of any collision risk model should be evaluated against any other available
indicators of likely mortalities, such as experience with comparable bird species at existing
Draft National Wind Farm Development Guidelines – 2 July 2010 Page 125