Koalas and Fire Management

Submission on the Draft Bushfire Risk Management Plan for Sutherland 2023

Tendered to Sutherland RFS 30/11/23

Cover Illustration
Mothers and JOEYS OF 2023

Top to bottom:

1. Mario (mother Polly not in frame), Engadine.

2. unnamed mother & Joey Mill Creek

3. Natalie & Woody, Mill Creek

4. Maryanne & Elli, Barden Creek

5. Perina & Omega, joeys paired together, Engadine

6. Linda & Milla, Barden Creek

7. Saint Sarah & Bailey, Heathcote National Park

8. Patsy & Ash, Heathcote National Park

9. Yin & Bo, Sandy point (almost Sutho)

10. Evie & Zara, Engadine

11. Bobbie & Austin, Lucas Heights

12. Judy and Tash

photo credits
1-9 Tom Kristensen (often with Steve Anyon-Smith)
10-11 Mel Clarke

Introduction

There is a well-documented, widespread koala population in Sutherland LGA with 190 individually identified animals, roughly equivalent to the estimated population of koalas in Campbelltown LGA. The Macarthur district also has a bushfire management plan currently on exhibition, but there is a major difference… Macarthur identifies koala habitat as a focus area but Sutherland doesn’t.

Both federal and state governments list koalas as an endangered species in NSW. Key threats to koalas include drought, fire and habitat fragmentation. The management of fire in the landscape will be crucial to the survival of koalas as climate change drives extreme conditions in the bush. Managing fire risk has seen an increasing demand for more hazard reduction burns, but setting widespread frequent fires in koala habitat between the unavoidable fire seasons might be contributing to adverse ecological outcomes.

Government Targets

The pressure from government to achieve large hazard reduction burn targets has put koalas in the way of unnecessary harm. While large-scale burning in remote bushland does deliver large HR targets it does little to protect housing. Indeed, frequent fire might be altering plant communities, decreasing the stock of koala feed trees and increasing the flammability of bushland. Frequent fire may suppress the cyclical recovery of koala populations, koalas need years to recover numbers after a bushfire. As a consequence, broad scale extinction may occur as a result of increasing local extinctions.

The koalas in the Sutherland shire belong to a larger population that extends west into Holsworthy military range and on to Campbelltown. These koalas are free of the chlamydial disease that affects other populations north and south. The close proximity of koalas to metropolitan Sydney should provide extra political
incentive to manage their wellbeing. As the public becomes increasingly aware of the existence of nearby koalas more pressure will be placed on fire management to deliver strategies that work to protect koalas.

Fire Impacts on koalas

To be clear on the impacts of fires on koalas, it’s worth understanding how koalas have evolved to cope with bushfires. Koalas have excellent territorial awareness and may seek shelter near water and in caves. If the fire is approaching from
one direction koalas are capable of moving ahead of a slow moving fire front. When overtaken by fire a koala is likely to climb a tall tree and attempt to sit it out. After a fire, surviving koalas will abandon burnt forest and attempt to resettle in unburnt habitat. Displaced koalas will be competing with other koalas and coping with the stress of surviving in unfamiliar territory.

To summarise, koalas can die directly from being burnt, from heat stress, from smoke inhalation or from longer-term decline from burns or airways injuries. Displaced koalas can then die from thirst, starvation, road strike or dog attack in attempting to establish new territory. The decline may take weeks or months to play out as koalas try to cope with the aftermath of the fire.

RFS Response

Sutherland RFS are concerned about koalas and have told the public about “having koalas top of mind in planning burns”. Unfortunately that concern is not yet developed in the draft bushfire risk management plan for Sutherland which
only refers to the existence of an Area of Regional Koala Significance without defining where that area might be and how it might relate to fire planning. There are no specific measures for koala conservation mentioned in the draft plan

RFS recently delivered a set of assurances in announcing an extensive burn in Holsworthy Military Range. As reported by Kelly Fuller, Friday 8th September, on ABC Illawarra, the following promises were made regarding koalas:

“Koalas at forefront of planning for major hazard reduction burn in Sydney’s south
west, RFS says”
“Illawarra/Sutherland RFS acting manager David Barnett (sic) said a lot of planning had gone into preparing for the burn and it would be conducted along guidelines developed for threatened species. … So that means having a fire [with] a half to one-
metre flame height and trying to keep … the upper canopy out of the fire. … The burn will be conducted from the northern edge of the identified area, southwards down each side. … What that does is it allows the koalas and other wildlife … to move out of the path of the fire – hopefully without getting burnt or anything – giving them the
opportunity to get into refuge areas as well. … The RFS will use an aircraft with an infra-red camera to conduct a thermal heat survey. Firefighters on the ground will also use the cameras to conduct visual inspections. So if they see any koalas, their objective is to hold the burn until the koalas are able to move on – we won’t burn them out – we have got them front of mind.”

Such promises may be well-meaning but they are unrealistic and impossible to deliver. RFS are incapable of finding any meaningful fraction of koalas living in a burn area of 27 square kilometres. (See Figure 2) RFS volunteers have no training in finding koalas and have their hands full controlling an active fire. The proposal to deal with koalas on the day of the burn is equivalent to doing nothing.

Unfortunately RFS are also challenged in delivering a fire with a flame height between half and one metre. The intensity of fires delivered this season has exceeded the prescriptions in dramatic terms; with widespread heavy use of aerial incendiaries and thick black smoke plumes indicating intense fire. Post fire surveys also confirm that prescriptions were exceeded (see Appendix A & Figure 1)

Bushfire Management Committee Response

I have previously been approached by RFS and Sutherland Shire Council to provide advice on koalas, and over the last two years I have offered numerous verbal briefings and written suggestions, and recent koala mapping information, to Sutherland RFS Hazard Reduction Burn Planning Team. This current submission should hopefully serve as a reminder of information already put
before RFS and other members of the Bushfire Management Committee. The major landholders have all been made aware that they have koalas under their protection. Anyone is free to obtain information on the management of koalas from the NSW DCCEW koala team. Mapping of the known distribution of koalas in Sutherland is freely accessible on the Bionet database (See Figure 2)

Recommendations

• Bionet records of koalas should be examined and included in burn plans
• Burns in koala habitat should include surveys for koalas before and after
  burns
• Bushfire Risk Management Committees should include an ecologist, or
  Technical Advisor Wildlife, able to advise the RFS Incident Management
  Team. That person should engage with the community on koala surveys.
• Each burn in koala habitat should trigger a site report to inform future plans

Appendix A

Koala Survey of Deepwater, Woronora Heights
Before and after Hazard Reduction Burn of 15/7/23
Tom Kristensen for Sutherland Shire Council and others. 12/9/23

Introduction

This report presents evidence of koalas in the hazard reduction burn area known as Deepwater at Woronora Heights in Sutherland shire. The shire is home to a large population of koalas as established by broad survey work across a range of sites conducted in the last two years. Each site containing core koala habitat is an important piece in the map of koala occupancy with koala movements recorded between sites. The Deepwater site represents the end of koala distribution along the Woronora River and a staging area for population expansion into the Forbes Creek catchment to the southeast and Bangor to the northeast. See Map 1.

At least three koalas are known to use the Deepwater area. Recent sightings are of the large male, named Sydney Water. In February there was a sighting of a small sub-adult named Theo. It is assumed there is also a female using the area, mother to Theo.

Council inspections confirmed that koalas did occur in the area before and after the hazard reduction burn. Koalas have survived the burn but may now have moved away from the burn area. While the burn was generally of low intensity, important koala feed trees have also been killed in this burn. See Fig 3

Burn Area

Deepwater burn area covers the west facing slope below Woronora Heights down to the Deepwater Estate on the flats of Woronora River. The area within containment lines set out by formal fire trails covers 27 ha.

Following approaches from council and RFS in early July Tom Kristensen was asked to advise on koalas in the proposed burn area. Before the burn two site inspections were made with Kevin and Graham. Information was relayed to Phillip Rook, an RFS HR burn plan manager and member of Sutherland Bushfire Management Committee. Given feedback on koala occupancy the RFS burn plan was reduced in area from 27 ha to 20 ha. The burn was carried out by RFS on the weekend of July
15-16 with the lower section of the site where koalas were previously seen excluded
from burning. See Map 1.

Research Team

Koalas are listed as endangered species under both the current state Biodiversity Conservation Act 2019 and federal EPBC Act 1999. Responsibility for managing koalas affects all land managers. Local koala conservation efforts are coordinated by
Joe Stammers of the Southern Sydney Koala Management Team, DCCEEW. Photographs of koalas in the area were provided to council by Steve Anyon-Smith and Tom Kristensen (BSc ecology USyd) both active Bushcare volunteers at
Sutherland Shire Council. Steve and Tom have been surveying koalas in Sutherland shire for last two years, building an ID guide for 180 individual koalas based on nostril patterns. Steve has been briefly contracted by council to find koalas.

Site inspections for council were conducted by Kevin Seymour, head of Bushcare, member of Bushfire Management Committee, now retired, and Graham Avery who is the Natural Areas Aboriginal Heritage Officer from the Bushland Unit under Open Space Operations at Sutherland Shire Council.

This survey of the Deepwater koala population is part of the Sutherland Shire Council’s Open Space Strategy 2021, and Delivery Program and Operational Plan 2022-2026. It falls to the Natural Areas Aboriginal Heritage Officer to help ensure
that any of the threatened species including koalas and their habitats are protected during hazard reduction burns. Kevin has been the chief instigator of this report.

Bionet Records

Sighting records for two koalas at Deepwater have been entered onto Bionet. While it is assumed that Bionet is a primary tool for RFS and ecologists preparing burn plans, it is evident that Bionet cannot provide sufficient and timely detail to effectively manage koalas, cryptic creatures able to travel large distances. Knowledge of occupancy and the extent of core habitat requires additional survey work

Three council inspections at Deepwater occurred between July and September 2023. On each occasion koala scat was found which could have been used to file a Bionet record, however the cumbersome nature of Bionet outweighs the benefit derived from entering multiple scat records. Previous survey work in Deepwater had been carried out by Steve Anyon-Smith and Tom Kristensen who provide koala sighting data to
the Koala Management Team, Jodie McGill at NPWS, and to Sutherland Shire Council. Each of these agencies has taken shared responsibility for entering some of the 465 sightings collected by Steve and Tom, with data for Deepwater bundled into this backlog. It seems that the work of entering data onto bionet is exceeding capacity and few entries appear in Sutherland for the year 2023.

Observations

Freshly burnt areas represent a unique opportunity to easily observe scat on a black background, with a clear timeline An inspection made on September 5 after the burn revealed extensive koala scat dropped in burnt areas, vindicating the decision to treat the area as occupied by koalas regardless of whether they were observed by RFS on the day of the burn. The scat was from at least two different animals given clusters of different sized scat. Besides koala scat the burnt areas revealed scat dropped by wallabies, brushtail and ringtail possums. See Figure 2

Sutherland koalas are most often seen occupying grey gums, Eucalyptus punctata, and these trees reveal the most claw scratches having a soft smooth bark. Based on sighting records the second most favoured trees are the Sydney peppermint,
Eucalyptus piperita, which has a fibrous bark that is more difficult to read for scratches. After the burn clearly evident scat fields indicate that koalas, large and small, were favouring peppermints over grey gums in the burnt area. No fresh green scat was found, all scat was copper-coloured and estimated to be a month old.

Section of the burnt area reveal high canopy scorching and the collapse of large peppermints fully consumed by fire. Peppermints are particularly vulnerable to repeated fires due to their low branching trunk structure, which is easily “piped” by fire at the base. Given the preference by koalas for these trees future burn plans might take this susceptibility into account.

Photographs of a young sub-adult koala named Theo provide a good match with a public sighting of a koala found in the grounds of Woronora public school on August 30, six weeks after the burn. Theo was first seen sheltering in the turpentine grove at the northwestern corner of the site. To reach the school Theo may have used footbridge to cross the Woronora River, the only crossing available, or he may have swam over. Koalas are known to seek out new territory after a burn has affected the quality of habitat. The disruption of koalas after burning may take months to play out as koalas compete and explore for new territory.

Conclusions

This report is best understood if read together with the RFS burn plan which speaks to fire intensity and the Review of Environmental Factors regarding koalas. Fire intensity should be planned with a view to preserving koala habitat as well as avoiding immediate harm to koalas. The REF suggests burns will be held off if koalas are observed on site, this is clearly an inadequate precaution given that koalas are not easily observed. Koalas should be assumed to be present where there are clear signs and recent sightings.

More inspections and mapping will add to our understanding of koalas living in the area and help shape fire planning. It is hoped future surveys across the shire will be conducted before and after burning to build a broader knowledge base. Ideally
knowledge of koalas would be easily accessible to be shared amongst land managers and others with an interest in conserving koalas.

There is a clear need for staff trained in ecology to co-ordinate further surveys and provide advise to land managers. It is also likely that increasing community awareness of koalas will drive a need for more community engagement by managing
agencies.