Byron Flora and Fauna Study 1999 - Byron Shire Council

A GREENPRINT FOR A SUSTAINABLE FUTURE
(e.g. identifying areas considered likely to provide habitat for Threatened flora and fauna species, such as
remnant rainforest and old growth eucalypt forest). The mapping component provided data on extent of
remnant and regrowth native vegetation, extent of Camphor Laurel cover and an indication of the areal
extent of different vegetation associations present in the Shire.
4.2 PREVIOUS STUDIES
The vegetation of Byron Shire had not previously been mapped, although parts had been treated in studies
using differing methodologies (Table 4.1). As some aspects of vegetation cover change relatively quickly,
often it is only the most recent studies which are useful as an indication of current vegetation.
In June 1996 Landmark Ecological Services Pty Ltd was engaged by Byron Shire Council to carry out a pilot
vegetation mapping project as part of the planning for the major flora and fauna study of the Shire (Milledge
and McKinley 1996). The principal objective was to design a vegetation mapping system incorporating
structural and floristic attributes at a scale of 1:25,000 which would provide sufficient detail to be useful for
land use planning purposes. The area selected for the pilot project comprised the coast and hinterland
about Cape Byron and Byron Bay.
4.3 RECOMMENDATIONS FOR BYRON FLORA AND FAUNA STUDY
(based on Milledge and McKinley 1996)
A multi-attribute approach with vegetation structure (following Walker and Hopkins 1990) as the primary
classification variable was initially used for vegetation mapping but this resulted in an extremely complex
map, difficult to interpret and of limited use for land-use planning. The complexity was primarily due to the
highly disturbed nature of the pilot project area, which has resulted in a mosaic of regrowth communities
with rapidly changing structural attributes. For example, major differences were apparent in the height and
density of some stands as depicted in the 1991 aerial photographs and as they presently exist. Even if
mapped in current form, it is likely that these stands would be structurally different again in a few years.
While structure may change rapidly, floristic changes tend to be slower. Mapping based on floristics produced
a more homogeneous map, which allowed easier interpretation and provided useful information more
readily.
The Pilot Study was intended as a multi-attribute approach with structure as the primary classifying variable
but the method proved to be impractical and was abandoned in favour of a mapping system using floristics
as the primary classification variable (Milledge and McKinley 1996). The latter method adopted floristic
communities and associations as mapping units identified by dominant species in the upper stratum, although
structural attributes were also included in the classification as a secondary variable, identified by a coding
system.
4.4 METHODS
4.4.1 Aerial Photographic Interpretation (API)
Interpretation of aerial photographs for the purpose of vegetation identification is a cost effective and
proven method for mapping large areas of vegetation.
Identification of various vegetation types is undertaken in the field and identified via the use of a stereoscope,
with the corresponding features on the photo. Field observations are then extrapolated and marked onto
plastic overlays on the photo.
Accuracy in API is dependent on several factors. These include the age and quality of photographs, the
accessibility of areas for fieldwork, and the amount of resources and therefore time available for both the
fieldwork and the mapping.
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