Updated August 2025
This preliminary report focuses on Gamba Grass outbreaks at Lee Point peninsula on land managed by DHA, in particular future conservation areas. It consists of photos taken in 2024 and 2025.
Fig 1. East of dam – start of firebreak (upgraded firebreak) – Gamba Grass within 15m of fence, 26 Aug 2025
1.0 Background
Changing land use, fire and erosion are having a significant impact on the habitats and wildlife on Lee Point peninsula.
In relation to fire, Gamba Grass first appeared on Lee Point peninsula around 2020. It is highly invasive and kills off native vegetation and wildlife through intense heat.
The old-growth tree below was estimated to be over 400 years and contained valuable tree hollows for wildlife. It was killed by a Gamba Grass fire in 2023.
Fig 2. Old-growth tree (84cm diameter Stringybark) after late August 2023 Gamba Grass fire – it never recovered.
DHA manage two planned conservation areas on the Lee Point peninsula;
- DHA Muirhead North – 50m Gouldian Finch buffer (0.4ha)
- DHA 2CRU offset (21ha)
The 50m Gouldian Finch buffer was announced by Federal minister Tanya Plibersek in June 2023 to reduce the impact from the DHA housing project, see yellow area in map below.
Fig 3. Lee Point peninsula showing land managed by DHA (outlined in green and red). DHA conservation areas (21 ha) are west of Stage 3 and a 50m buffer (0.4ha) in yellow.
2.0 Conservation Area – DHA Muirhead North: 50m Gouldian Finch buffer (0.4ha)
Half of Muirhead North is believed to have Gamba Grass outbreaks that could threaten up to 15% of Lee Point’s remaining old-growth trees. The majority of the (35) old-growth trees in the 50m Gouldian Finch Buffer are at risk, particularly if a Gamba Grass fire were to occur late in the dry season as it did last year.
The photos below were taken along the buffer fencing.
Fig 4. West of dam – Gamba Grass approx. 100m from fence, 10 June 2024
Fig 4b. West of dam – Gamba Grass approx. 100m from fence, 26 Aug 2025
Fig 5. South of dam – Gamba Grass within 50 metres of fence, 10 June 2024
Fig 5b. South of dam – Gamba Grass within 50 metres of fence, 26 Aug 2025
Fig 6. East of dam – start of firebreak – Gamba Grass within 10m of fence, 10 June 2024
Fig 6b. East of dam – start of firebreak (upgraded firebreak) – Gamba Grass within 15m of fence, 26 Aug 2025
Fig 7. East of dam – Gamba Grass within 10m of fence at east end of Gouldian Finch buffer, 10 June 2024
Fig 7b. East of dam – 11 Sept 2025
3.0 Conservation Area – DHA 2CRU offset (21ha)
Only part of 2CRU (DHA Conservation Area) was viewed for Gamba Grass.
Scattered Gamba Grass outbreaks were seen June 2024 along bike tracks throughout 2CRU offset area.
Fig 8. Gamba Grass outbreak in 2CRU – DHA conservation area on bike track, June 2024.
Fig 8b. Gamba Grass outbreak in 2CRU – DHA conservation area on bike track, Aug 2025.
4.0 2CRU housing area west of Lee Point Road
Only part of the 2CRU – DHA housing area could be viewed for Gamba Grass in June 2024. Some areas posed a significant fire threat to habitat.
Fig 9. Gamba Grass outbreak in 2CRU – DHA housing area approx. 100m west of Lee Point Road, June 2024.
Fig 9b. Gamba Grass outbreak in 2CRU – DHA housing area approx. 100m west of Lee Point Road, Aug 2025.
Fig 10. Gamba Grass outbreak in 2CRU – DHA housing area, June 2024.
Fig 10b. Gamba Grass outbreak in 2CRU – DHA housing area, Sept 2025
Fig 11. Gamba Grass outbreak in 2CRU – DHA conservation area on escarpment, Sept 2025
5.0 Discussion
The threat Gamba Grass poses to biodiversity is well recognised. In September 2022, Minister for Environment and Water Hon. Tanya Plibersek announced $9.8m over 4 years to tackle the Gamba Grass problem in the Top End.
At present, the number of old-growth trees at risk from a Gamba Grass fire on DHA land is significant in terms of those remaining on the Lee Point peninsula.
Gamba Grass is unlikely to be eradicated from the Lee Point peninsula without a coordinated weed management plan for the peninsula. Having a comprehensive Area Plan (to determine land use) for Lee Point supported by the community will help in producing such a plan.
The community does not support the DHA housing project at Lee Point and an alternative location needs to be found. A comprehensive Area Plan (to determine land use) needs to be completed for the Lee Point peninsula by an independent body before any significant development should be allowed.
Until these planning matters are sorted out, an interim weed management plan to control Gamba Grass (and other invasive weeds) should be implemented on DHA land now. Dealing with the problem early will reduce damage to native shrubs and trees. The requirements are clearly set out in the NT Government’s landowner responsibilities.
The land vested in DHA at Lee Point is a community asset and adjoins conservation reserves. As such, the weed management plan produced by DHA should be freely available to other stakeholders ie. published on DHA’s website. Coordinating efforts with other stakeholders will help reduce future Gamba Grass control costs and improve its effectiveness.
Casuarina Coastal Reserve (CCR) Land Care Group started mapping outbreaks of Gamba Grass in CCR in 2021 and provides an on-line map – refer to CCR Landcare Group Resources.
6.0 Summary
Not all areas on DHA land could be inspected for Gamba Grass in June 2024 and Aug 2025. However, major Gamba Grass outbreaks were seen in the planned DHA conservation and housing areas.
At present, the number of old-growth trees at risk from a Gamba Grass fire on DHA land is significant in terms of those remaining on the Lee Point peninsula.
It is highly likely that unless action is taken to control the growth and spread of Gamba Grass on DHA land the Gamba Grass problem will worsen.
It is recommended that a weed management plan in accordance with the NT Government’s landowner responsibilities be published on-line and implemented now by DHA to;
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- control the worst outbreaks of Gamba Grass on DHA land, and
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- help coordinate the control of Gamba Grass on the Lee Point peninsula with other stakeholders.