Environmental Engineering Reference
In-Depth Information
farm facilities to-date in Australia. Other possible effects of wind energy generation
include disturbance of fauna during construction and operation, and alienation of
habitats that may be caused by wind farms.
This paper focuses on wind energy facilities in south-eastern Australia. It is
important to understand some key aspects about bird and bat populations and their
ecology in this area, especially as these aspects may compare with bird and bat
interactions with wind turbines elsewhere. Australian wind energy facilities are
presently confined to on-shore locations and there is no current expectation of off-
shore development. Current and proposed wind farms are situated in both coastal
and inland areas and the majority of them are within substantially modified agricul-
tural environments.
Manyspeciesofbirdsandbatsthatcouldbeatriskofcollisionsareresidentat
the sites of wind farms all year. South-eastern Australia also has a significant num-
ber of species that are nomadic or migratory and may be present episodically or for
regular portions of the year. International migratory species include shorebirds,
largely of the East Asian-Australasian Flyway. South-eastern Australia forms a por-
tion of the non-breeding destination for most of these species and their distribution
when here is quite widespread and responsive to variable local availability of
resources. Some other international migratory species breed in south-eastern
Australia. The most notable of these is the short-tailed shearwater
Ardenna tenui-
rostris
which congregates in the millions of birds at traditional coastal colonies.
There are also numerous species that migrate within Australia. These include
species that move seasonally between higher and lower elevations or between north-
ern and southern portions of their range. Amongst the latter, a diverse range of taxa
move annually between Tasmania and the mainland. Some of these undoubtedly
traversetheshorterofpotentialroutesacrossBassStrait.Whileourknowledgeof
this migration is generally poor, some of these movements appear to be diffuse
rather than following defined routes. Some species, like the brolga
Grus rubicunda
inVictoria,makeseasonalmovementsbetweenkeyresourceswithintheregional
landscape.Mostbatsintheareaareinsectivorousresidentsthatshelterintreehol-
lows and forage within treed environments, including around scattered trees in agri-
cultural areas. A few species routinely use caves for roosting and to overwinter.
These bats also forage widely across the landscape but females seasonally congre-
gate at a select few maternity caves.
Across this variation in ecological and behavioural traits, the great majority of
bird and bat flights that are at risk of turbine collision occur during routine activities
whiletheanimalsarepresentintheareaofawindfarm.UnlikeNorthAmericaand
Europe, the region does not have defined migration pathways used by very dense
aggregations of migratory species on passage.
This review considers the current state of knowledge about bird and bat colli-
sionswithwindturbinesinsouth-easternAustralia.Itisbasedlargelyon15years
ofexperiencebyBiosisinbiodiversityassessmentsforwindfarms,especiallyour
investigations of the potential and actual effects on birds and bats. A primary aim of
the review was to evaluate the level of mortalities caused by collisions with turbines
and any trends that might be apparent across wind farms now that some of them
