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Attachment 3 - Koala Impact Assesssment
RACV – NOOSA
Advice regarding koalas and development
proposal at Lot 3 on SP 126203 Noosa Drive
27 June 2022
Proposal for 16 Eco-Cabins providing for short-term accommodation
integrated with the existing RACV Noosa Resort (Resort Complex).
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Ecoteam Scientific P/L. This report has been produced for the use of and remains the property
of Aspect Architects and does not constitute legal advice. No third-party rights are granted. This
report is to be referred to as: Ellis (2022_5) RACV Lot 3 on SP 126203.
Ecoteam Scientific 27 Dudley Street T 0428105275 E [email protected]
PO Box 6154 Bardon Qld 4065 ABN: 53705278586 W www.koalascience.com
St Lucia Post Office
Qld 4072
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Summary
This report addresses a proposed development of Lot 3 on SP 126203 for 16
Eco-Cabins providing for short-term accommodation integrated with the existing
RACV Noosa Resort (Resort Complex) and should be referred to as Ellis
(2022_2) RACV Lot 3 on SP 126203.
The proposed design of tourist accommodation amongst core koala habitat at
the site reflects advice I have provided, based on 1) inspections of the site and
surrounds 2) discussions with the proponent and 3) consultation with a koala
expert engaged by Noosa Council.
The proposal now incorporates a) the retention of safe internal connections, b)
improvements to quality of the retained habitat c) augmentation of current
habitat quantum and d) design (cabin siting) to reflect adjacent habitat
connections and quality. Further opportunities to improve surrounding koala
habitat exist, which could increase the benefit to koalas and other fauna in the
local area, and these should be a part of a larger, coordinated approach with
council. Considering the speed of degrading ecological processes on the site,
the current proposal offers an alternative for this location that has positive
outcomes for koalas in Noosa.
The current proposal is the fourth iteration I have reviewed, each incorporating
more elements designed to mitigate impacts and improve the outcome for
koalas and other fauna at the site, in response to advice of ecologists.
Increased tree retention and improved vegetation management outcomes
promote general permeability and on-site safety for koalas and demonstrate the
effort to meet the demands of development in such sensitive ecological
surroundings.
The site and the proposed development
Under the Noosa Plan 2020, the 6.4 Ha (approx.) site is mapped as connecting
habitat area, tourist accommodation, area of biodiversity significance and is
subject to the Biodiversity, Waterways and Wetlands Overlay Code. The land is
mapped by the State as Category B remnant vegetation and, significantly, has
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recently been mapped as core koala habitat. It lies outside of a Koala Priority
Area.
With Eucalyptus robusta, a known koala food tree, common across the subject
site, its value to koalas lies in both food and shelter resources. However,
encroachment of weeds, particularly frangipani vine (Chonemorpha fragrans)
threatens the habitat quality for koalas, strangling the canopy and hindering on -
ground movement of koalas.
The site is mapped as Melaleuca dominated palustrine wetlands (seasonally
inundated open forests and woodlands) joining Eucalyptus open forest to the
north along Noosa Drive and heathlands and associated scrubs behind the
current RACV resort site. The potential connections (with respect to koala
habitat) are narrow beyond the site boundaries to the north and south,
consistent with the regulated vegetation mapping, indicating a narrow band of
appropriate vegetation extending north, with some southern connection to
Leslie Park and Weyba Bridge Park, fringing the mangrove and heathlands. As
a result, the site forms part of a bisected patch of habitat that could provide
refuge for in-transit koalas moving between the larger patches associated with
Noosa National Park to the north and bushland to the south of Eenie Creek Rd
(Figure 1).
The tenuous links notwithstanding, the management of patches of habitat such
as this site are vital for the persistence of koalas around Noosa. If this site
continues to degrade because of tree death caused by engulfing vines, the
north-south avenue for movement of koalas will be further diminished or lost. A
careful approach to the development of the site, however, could ensure the
quality and quantum of koala habitat is improved.
Acting together, the subject site, council reserve and Leslie Park (across the
busy Noosa Drive) constitute a significant node of koala habitat for the local
area.
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Figure 1. core koala habitat mapped for the area (2020)
In 2008, under the Integrated Planning Act 1997, an application was approved
to establish multiple (10) units on the site (Figure 2). In consultation with
ecologists, that approval lapsed, and two improved (interim) proposals were
developed (Figures 3 and 4, in 2019 and 2021), before the current proposal was
developed. The current approach seeks to establish “eco-cabins” (Figure 5)
amongst the natural vegetation, retaining connections for ground based and
arboreal species by building above the ground. The interim proposals (Figures 3
and 4) were previously considered by the ecologists and because of feedback
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provided to the proponent, a solution with less ecological impact and greater
provision for koala resources was developed (Figure 5).
The original, approved proposal (2008) (Figure 2) envisioned ten units across
the site with vehicular access to each unit. Most trees would be removed, and
the area would not be habitable by koalas. Revegetation of the eastern
boundary would compensate for some loss of habitat, but the proposal would
not conform to the expectation of a koala-friendly development today and the
proponent has moved away from this design.
Figure 2. Original (approved 2008) proposal for the site.
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The interim 2019 proposal (Figure 3) still proposed the removal of almost 60%
of the 108 NJKHT identified on site; importantly, of the 66 E. robusta comprising
the NJKHT on site, 39 (59 %) were identified as “to be removed”. The planning
scheme in place at the time (2019) did not map the site as core koala habitat,
but the design was nonetheless directed towards creating a permeable
landscape for koala movement. No internal barriers other than the building
envelopes were created, but there was an unacceptable loss of trees,
particularly in the west, where the property bounds koala habitat on council
land.
Figure 3. 2019 proposal - prior to amendments
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As a result of the concerns raised, a further modified proposal was developed
(Figure 4a and 4b).
Figure 4a. Amended proposal for development at the site.
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Figure 4b. Tree retention map, proposal version 3.
Despite the significant improvements inherent in “version three” of the proposal,
the design team and the ecological experts identified further potential gains in
tree retention with some minor adjustments to the design. The realignment of
the parking area has protected more koala food trees and is augmented by
shifting cabin locations to maximise tree retention (koala food and habitat trees)
resulting in the current proposal (Figure 5).
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Figure 5. Current proposal for development at the site.
A feature of the current proposal is the retention of high value trees on the site
(Table 1) including 86% of the eucalypts present, achieved through changes to
the layout of the cabins, parking allotment redesign and realignment of
walkways to avoid specific trees.
These changes over time demonstrate a responsive approach to development,
realising the value of the retained trees to koalas. Further work is envisioned
that will enhance the quality of koala habitat within the site – particularly through
the removal of weeds which threaten the future of many eucalypts on site and
the replacement of trees in poor health.
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Table 1. Tree retention under the current proposal (from Consult Arborist).
Tree Value Remove Retain % Retain
High Retention Value 29 175 86
Medium Retention Value 46 92 55
Low Retention Value 24 9 28
Total 99 276 74
Tree Species
Eucalypts 20 127 86
Paperbark 29 66 31
Other 50 83 58
Total Trees Recorded 99 276
Impacts and their mitigation
A complete tree survey of the whole site was conducted in March 2022,
individually identifying and describing 375 trees. Of these, 135 were identified
as Eucalyptus robusta, and four as E. tereticornis – key food species for koalas
at this location. Importantly, the tree survey also inspected each tree for
maturity, form, and health, noting the presence of invasive weeds and decaying
limbs.
Previous proposals that were considered for this site envisaged a significant
proportion of the extant trees be removed; as part of the actions to mitigate and
avoid impacts, the present proposal foreshadows (subject to detailed design –
see Table 1) the removal of approximately twenty E. robusta, i.e. the retention
of most of the available fodder species on site. This is an appropriate effort
retain as much habitat, and to do so as part of a strategic approach - retaining
spatially strategic trees to retain connectivity rather than simply retaining trees
where convenient.
Importantly, the status of the trees on site was carefully examined during the
tree survey, and significant health concerns were identified for many of them. A
key problem facing this site is the infestation of weeds, particularly climbing
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vines which are degrading the health of the existing trees and depriving the site
of opportunities for improved ecological conditions – particularly as they relate
to the availability and accessibility of koala food resources. Combined with
impediments to ground movement by koalas, the current prognosis for koala
habitat at the site is poor; the long-term prognosis for the retention of many of
the koala resources at the site is poor without intervention to remove weeds and
replace decaying trees.
Of the koala food species identified for removal to accommodate the current
plan, some six to ten are identified as requiring significant intervention in order
that they do not die in their current state. Only a few trees are free of weed
infestation, and many are showing signs of poor health (Figure 6).
Figure 6. Vine infestation is overtaking much of the site.
This state of health for the trees within the design footprint is reflected across
the site; the prognosis for the retained koala food trees is similarly poor, but the
proposal includes actions to reverse this and improve the outlook considerably.
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The evolution of the design at this site, reflecting advice across the separate
proposals over time, has been toward a design that retains as many trees as
possible, avoids impediments to the movement of koalas and augments habitat,
providing increased food availability, clear ecological management zones and
an enhanced outcome for koalas that may use the site. Strategic placement of
units should augment the area to the west of the property – moving from
iteration 2 to 4, units have been moved away from the boundary (and one set of
units abandoned altogether) to retain a significant group of trees (between
current units 2 and 3). Several stands of trees are now retained in strategic
locations, retaining a permeable vegetated landscape within the design area,
and reducing impacts at the boundary to the west and south of the property. It is
possible that further amendments in the detailed design will allow retention of
more trees – such as tree #44, which may be retained without creating a
blockage to movement of guests.
These actions are to be augmented with a weed control program, a planting
regime and attention to the replacement, where necessary, of diseased and
dying trees with healthy young trees. Trees that are in poor health and likely to
die or have very limited value as koala habitat will be replaced with healthy
young E. robusta, placed so as not to conflict with structures.
Weeding will focus on removing the climbing vines which are encompassing
canopies across the site and restricting movement through the site. Where
these vines have caused irreparable damage to the koala food trees, those
trees should (and are proposed to) be replaced, either in the same location or
as part of the planting regime. Plantings in the south of the property will provide
both a visual screen for the units and habitat for a range of species over time. E.
robusta is a fast-growing eucalypt in coastal conditions and should be preferred
as a species for planting due to its function as a food resource for koalas.
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The proposal within the planning scheme
The site is mapped as core koala habitat, but it is not within a koala priority
area, hence development that interferes with koala habitat is not per se
prohibited development and can be assessed against the various planning
instruments.
Noosa Planning Scheme 2020
The Noosa Planning Scheme 2020, expressed in the Biodiversity, Waterways
and Wetlands Overlay Code intends that development:
“…is designed, sited, constructed and operated to avoid or minimise
adverse impacts on koalas and their habitat and to provide for connectivity and
safety for the long-term viability of the koala population.”
Further, criteria for assessable development states that it must:
a) protect and enhance koalas and koala habitat and avoid adverse
impacts;
b) provide measures to assist the survival of koala populations in the area
to mitigate any potential threats or risk to koalas; and
c) provide for safe and appropriate koala movement across the landscape
The acceptable outcomes in Table 8.2.2.3 of the Noosa Plan 2020 are:
11.1) Development design complies with the Koala sensitive Design
Guideline: A guide to koala sensitive design measures for planning and
development activities.
11.2) Development incorporates revegetation and landscaping that
provides food, shelter and movement opportunities for koalas.
11.3) Development is designed to maximise and enhance connectivity
between koala habitat trees and ensure safe koala movement.
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11.4) During construction, measures are incorporated to not increase
the risk of death or injury to koalas, by including safe koala movement
measures, as defined in the Planning Regulation2017.
Response to the Noosa Plan 2020
Development in koala habitat should result in a net positive outcome for koalas,
regardless of the mapping designation of the subject land. The reduction in
koala habitat is a major cause of koala population declines across the species’
range, and in some cases, development should not occur at all. At the present
site, the impact of climbing vines on the health of trees and the incursion of
weeds through the undergrowth does not point to a healthy ecosystem able to
meet the habitat requirements of koalas into the future. What facility exists in
terms of food resources, resting places and easily traversed understory has
reduced over time and this trend is likely to continue unless there is some
intervention. A similar prognosis exists for the council reserve adjacent to this
site, and a co-ordinated approach to weed removal should be undertaken.
Further, the planting of koala food and habitat trees for revegetation and
landscaping addresses the Noosa Plan 2020 providing food, shelter, and
movement opportunities for koalas. The Noosa Plan 2020 is also addressed in
the placement of units, especially at the western boundary, where the setback
and habitat enhancement (through weed control, tree retention and
revegetation) is designed to maximise and enhance connectivity between koala
habitat trees and ensure safe koala movement.
The design aims to protect and enhance koala habitat and avoid adverse
impacts by retaining those features (trees and connectivity) crucial to koala
habitat function, but also through a long-term approach to managing the habitat
with weed management, replanting and replacement.
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In accordance with the Biodiversity, Waterways and Wetlands Overlay Code,
the siting of the structures has been adjusted to avoid and minimise the loss of
trees. Retaining trees within the design area, facilitating movement for wildlife
through the site and adapting the unit design and access facilities is a response
to the need to “provide for connectivity and safety for the long-term viability of
the koala population.”
The proposal is for a low-light environment, with no-domestic animals permitted,
and no vehicular access in the koala habitat. Advisory signs and lighting will be
installed adjacent to the development to warn motor vehicle occupants of the
probability of encountering koalas. This should lower the risk of injury to koalas
from passing and accessing traffic, but also remind residents and visitors of the
need to be aware of koalas – hopefully assisting the survival of koala
populations in the area to mitigate any potential threats or risk to koalas. A
possible crossing for wildlife and pedestrians should be considered where the
council reserve (adjacent to the site) meets Weyba Drive / Noosa Drive, at the
point of the waterway.
Koala sensitive Design Guideline
The Koala-sensitive Design Guideline is a document produced by the
Queensland Government to provide advice and information for managers, land-
use planners, infrastructure providers and development applicants to determine
appropriate measures to help avoid and minimise the impact of development
and land-use planning on koala populations. Its principles are to retain food and
shelter values of habitat in a natural state, to achieve permeability for koalas
across the landscape and to reduce threats to resident and transient koalas.
Response to the design guidelines
The design guidelines are evident in the evolution of the current proposal –
particularly through increased tree retention and replanting, as well as the
raised infrastructure and strategically-retained canopy cover across the site.
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Strategically placed exclusion fencing to separate koalas from the risk of road
trauma in combination with koala-permeable fencing to encourage movement of
koalas in safer areas will meet the koala-sensitive fencing guideline. Prohibiting
dogs from the site will remove the risk of attack and signage will aid community
information on living with wildlife – another element of koala-sensitive design.
This will be challenging in the connection between the council reserve (toward
the creek) and the subject site because free access for fauna must be retained
to ensure the permeability of the landscape and avoid directing fauna to the
road (Noosa Drive).
State Code 25: Development in South East Queensland koala habitat
areas.
Because this proposal sits within mapped koala habitat in southeast
Queensland, any development that interferes with koala habitat must comply
with State Code 25: Development in South East Queensland koala habitat
areas.
The purpose of State Code 25 is to ensure development:
1) does not cause an unacceptable impact on mapped koala habitat areas;
2) is designed and located to avoid impacts or, where the matters of state
environmental significance cannot be reasonably avoided, impacts are
reasonably minimised and mitigated;
3) does not result in a significant residual impact on a matter of state
environmental significance unless the significant residual impact is acceptable,
and an offset is provided.
Within the development guidelines associated with State Code 25 lies a table,
guiding the approach to koala habitat based on patch size:
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Table 1: Guide for habitat patch sizes (State Code 25 Guideline).
Koala habitat area patch Habitat Use
size
≥ 50 Able to support a viable population of koalas.
High priority to maintain extent of patch.
≥ 2 ha and < 50 ha Medium priority for habitat, high priority for
restoration and revegetation, high priority for
connectivity.
< 2 ha Not considered large enough to support a
koala population but can function as a
‘stepping stone’ within a corridor.
The site is in the second category, being of medium priority for habitat, high
priority for restoration and revegetation, and high priority for connectivity.
The site is also serviced by an adjoining council reserve, extending the capacity
for connectivity, but also the possibility of site impacts affecting important
habitat off-site. It is important that any fencing between the subject site and
council reserve does not hinder koala movement.
Addressing State Code 25.
The site is now mapped as core koala habitat, and the reduced footprint and
habitat management features of the proposal are designed to avoid
unacceptable impacts on mapped koala habitat areas. The efforts to avoid and
mitigate impacts at the site are evident in the evolving proposal design, which
responds to and mitigates impacts where they cannot be avoided (e.g. tree
removal). As a result, the proposal should not result in a residual negative
impact on koalas or their habitat in the local area. The habitat size is
appropriate for measures designed to restore, revegetate, and connect koala
habitat in the area, all of which this proposal attempts to do.
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A co-ordinated approach to mitigating impacts.
Noosa Council is recognised for its emphasis on retaining natural ecological
assets within a major global tourist destination. Carefully planning development
to improve natural assets is an effective way to retain key habitat for native
species while accommodating the tourist influx that is drawn to the environment
of Noosa. Habitat areas that facilitate koala movement, provide koala food, or
are used for koala refuge require careful attention if development is proposed,
regardless of the planning designation of the area. For example, if a site is
primarily of benefit for connection, but provides little fodder, the integrity of the
environment is vital for koala movement, even though the tree composition may
change. Reducing its capacity to transport koalas by removing trees and
building impediments to movement could degrade its value significantly. The
current site presents a variety of resources to koalas: refuge, movement, and
food. Each of these habitat values must be retained for there to be no residual
impact on koalas, but by improving various elements it is possible to generate a
net benefit. Due to the shape and composition of the site, movement
opportunities occur throughout the site in multiple directions, and it is a wide
node along an otherwise narrow strip of vegetation. By placing units carefully
within the site and retaining most trees throughout the site, there is less
functional impediment to movement by koalas. Similarly, improvements to the
health of these trees should increase (enhance) the quantum of fodder available
to koalas using the site over time.
A recent feasibility report into koala infrastructure in Noosa (Ecology 2017)
recommended koala exclusion fencing be constructed on Weyba Rd (Noosa
Drive); where the proposed development meets Weyba Rd the opportunity
exists to assist council in meeting this recommendation. Because exclusion
infrastructure works more effectively with safe crossing structures, a
combination of the two is likely to significantly improve the connections for
koalas traversing Weyba Rd.
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Noosa council has also received recommendations for koala and wildlife
signage as a tool to reduce road trauma for this species (Ecology 2017):
combined with council imposed speed limits on Weyba Rd / Noosa Drive, such
signage could also result in an improved outcome for koalas. Because Noosa
Council has already considered the need and options for koalas in this specific
location (Weyba Rd – see Figure 14h in the Koala Infrastructure and Feasibility
Report (Ecology 2017)), the opportunity exists to address current and future
concerns for koalas in this location as part of the development proposal. Hence,
consideration of the recommended fencing upgrades and safe passages in
addition to the soft measures of vehicle speed control, lighting and signage off-
site (Ecology 2017) would enhance koala-positive outcomes on site as part of
this proposal.
Conclusion
In assessing this proposal, I considered the “do nothing” approach against the
“limited development” approach for the site. The koala habitat is degrading,
because of weed infestation, and without intervention the prognosis is not good
for many of the existing trees. The facility of the site for koalas is an important
element of the linking vegetation along Noosa Drive, and the site forms a node
of habitat that should be maintained and improved. Hence the proposal to
enhance the habitat through weeding, tree replacement and infill planting with
E. robusta warrants consideration in balancing some level of development (and
tree removal) at the site. As the design develops further with input from the
various technical advice (i.e. bushfire, geotechnical), some modifications may
develop and these are not considered (whether positive or negative) in this
assessment. As proposed, the design reflects input for developing a permeable
and safe koala habitat amongst tourist facilities and has the potential to
enhance koala habitat at the site in the long term, especially through the
retention and enhancement of koala food resources at the site.
Beyond the site, opportunities for planting along the northern connection are
limited by the placement of the overhead lines along the walking path adjacent
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to Noosa Drive, but to the south, there exists an opportunity for shared
community walkway / koala access infrastructure, for safe road crossing (of
Noosa Drive) and access to further bushland. These opportunities should form
part of a larger, future collaboration with council to improve koala resources in
Noosa.
References
Ecology, O. (2017) Koala Infrastructure Audit & Feasibility Report 1700860 a.
Planning and Environment Committee Agenda, Noosa Council.
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Attachment 1. Definition of Terms
Age Class:
Young: Early stage of growth, immature size
Early Mature: Fast-growing well-established tree which has not yet reached mature size
Mature: The tree reached its mature size, exhibits slowing growth rates with early stages of naturally forming dead
or dysfunctional wood.
Over Mature: The tree has reached mature size and is unlike to increase significantly in height or mass. Retrenchment of
the upper crown with increased vegetative vitality in lower crown, increased fungal activity and wood decay,
increase colonisation by flora and fauna.
Veteran: Tree with advanced retrenchment, reduced crown size and annual increment growth, extensive hollowing,
crown collapse, low vigour, advance heartwood decay, advanced colonisation by fauna and flora.
Health:
Good: Tree with no defects or disorders which are notable. Full canopy with good colour foliage. Minimal pathogen
damage.
Fair: Tree with minor defects or disorders which are notable. Some deadwood within what can be an unbalanced
canopy, foliage generally with good colour although some discolouration may be present typical of species
in location. Minor pathogen damage.
Poor: Tree with major defects or disorders which are notable. The tree has considerable deadwood present,
discoloured or distorted leaves indicating a further decline of the tree. Detrimental pathogen damage.
Dead: Dead or dysfunctional moribund tree.
Structure:
Good: Tree with good unions and no branch defects. Sound trunk with no / minor defects. Good buttress and root
structure.
Fair: Tree with minor defects or disorders which are notable. Small areas of bark missing. Small cavities or minor
unfavourable branch unions may be present. Minor damage to roots.
Poor: Tree with major defects, large hollows, weak unions and/or problematic damaged roots.
Hazardous: This implies a tree with a major defect that may fail at any time
Protection of Trees:
DBH: Diameter at Breast Height - The approximate diameter of the trunk is measured visually in millimetres at a
height of 1.4m.
TPZ: As specified in the AS 4970-2009 Protection of trees on development sites, the Tree Protection Zone (TPZ)
is the principal means of protecting trees on the development site. The TPZ is a combination of the root and
crown area requiring protection. This area should be isolated from construction disturbance so that the tree
can remain in a viable condition. The TPZ incorporates the Structural Root Zone (SRZ).
The radius of the TPZ is calculated for each tree by multiplying its trunk diameter at 1.4m above ground by
12, e.g. 300mm [email protected] x 12 = 3.6m Tree Protection Zone (TPZ)
A TPZ should not be less than 2m or greater than 15m (unless crown protection is required).
SRZ: Structural Root Zone (SRZ), as specified in AS 4970-2009 Protection of trees on development sites, is the
surface area of protection required to maintain a tree’s stability – a larger area is required to maintain a tree
in viable health. It is only necessary to calculate the SRZ when major encroachment into a TPZ is proposed.
The SRZ for trees with a trunk diameter less than 150mm will be 1.5m.
Tree Retention Value:
The retention value status is based on industry recognised methods of ascertaining the retention value of a tree. The suitability
of the tree for preservation or retention is based on the individual qualities of each tree. By taking into consideration the health,
structural condition, aesthetics, age, size, longevity (Safe Useful Life Expectancy) and ability to adapt to new environments the
viability of the tree can be reasonably determined.
For trees in non-use areas (e.g., Open spaces) where a range in tree quality is appropriate, all trees may be considered
suitable, except for invasive species.
Suitability for Retention/Preservation Categories are:
High: Tree retention is the priority.
The tree has high amenity, heritage and/or environmental value. It is in reasonably good condition (any minor
structural or health problems can be mitigated), has a long life expectancy and can recover from injury or
respond to environmental changes.
Medium: Tree retention is desirable.
The tree is in fair-good condition, is a locally common species, the tree contributes to the aesthetics of its
locality and should survive for many years. The tree may have health or structural problems that can be
mitigated with treatment.
Low: The tree is not considered worthy of special measures to ensure its retention.
The tree is in poor condition with significant defects that cannot be mitigated, has a short Useful Life
Expectancy, or the tree is expected to decline regardless of treatment. The tree has low value in the
landscape or is an undesirable species.
Remove: Tree removal is recommended.
Trees are considered potentially hazardous, very poor specimens, and/or may be environmental or noxious
weeds.
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