2016-12-12 General Committee - Attachment 1 to Item 6 - Biodiversity Assessment Report

                                                 Noosa Biodiversity Plan – Biodiversity Assessment Report




Altered fire regimes are an issue where weed incursion is a threat and is common in areas of concentrated
development. Recommended biodiversity conservation management actions should therefore include
educating the community on such issues as well as ensuring ecological fire regimes are taken into
consideration in fire management planning and actions as part of the implementation of Council’s Bushfire
Management Plan for Council bushland reserves.


4.5   Re c re at ion al U s e
Disturbances to vegetation communities caused by off-road vehicles, horse riding, bike trails or boating
can facilitate secondary impacts such as weed incursion, erosion and waterway sedimentation. Such
impacts can lead to altered fire regimes, nutrient loading of waterways and the degradation of biodiversity
values of habitats. Within Noosa, impacts from recreational use have been reported for montane heath
communities, narrow riparian rainforest communities, foredune communities as well as mangroves and
saltmarsh (Burrows, 2003). Recommended biodiversity conservation management actions should
therefore include developing strategies to address disturbances to vegetation communities and fauna
caused by recreational activities such as no-go zones and reduced speed limits, as well as maintaining
signage and bollards, particularly for migratory bird exclusion zones.

4.6   Deg r ad at i on
Ecosystems within the Noosa Shire are generally in good condition and the integrity of ecosystems are
high, particularly in the northern upper catchments of the Noosa River (Mackenzie et al., 2012). However,
there are areas where degrading processes have impacted on biodiversity values. Exotic plants and
invasive species are considered a primary cause of degradation and a significant threat for the Noosa
Shire (refer to Section 3.2). However, the risk of degradation that is associated with other processes
such as drainage of wetlands, erosion, sedimentation and nutrient pollution of freshwater and marine
waterways has varied over the years.

At present, the overall health of the Noosa River catchment is considered to be excellent, with all water
quality and aquatic habitat parameters meeting environmental values and water quality objectives as
listed under the EPP (Water) (SEQ Waterways, 2016). Results from the recent Ecosystem Health
Monitoring Program across SEQ indicate that overall all key processes are functional and habitats are
considered in near pristine condition (SEQ Waterways, 2016). However, there are portions of the
catchment, particularly in the lower reaches that in isolation show more degraded parameters.
Furthermore, over the last six years the health of the Noosa River system has varied for both the marine
and freshwater areas of the catchment. Various water quality and aquatic habitat attributes have showed
signs in the past of potential degradation.

In previous years for freshwater environments within the Noosa River catchment, health indicators relating
to nutrient cycling, fish and invertebrates have shown evidence of moderate disturbance (Figure 25). A
reduction in these indicates in the past suggests the input of elevated nutrient loads through either a point
source or diffuse source as a result of vegetation removal. Increased nutrients and the subsequent
invasion of weeds has been reported for a number of coastal creeks in Noosa, including Burgess Creek
and sections of Marcus and Castaway Creeks (Burrows, 2003).




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