Description of release sites

The vegetation complexes for all 3 of our release sites  were described by Mattiske/Havel (Mattiske and Havel, 1998) and have been resurveyed by Webb. (Webb et al, 2016). 

The species lists and observations were provided by Cherie Kemp (personal correspondence).

Site A
Site A encompasses  approximately 180 acres / 70 ha of near-pristine, mixed bush including  several smaller peppermint dominated areas.
It is bordering state forest/national park, paddocks and a minor road with adjacent vineyard and has a well-established path system throughout. Several creek lines dissect the property and a dam with swampy surrounds (constant water) make a part of the area prone to flooding.
The property contains C1 and Cw1 vegetation complexes (Cowaramup) that have high importance for protection as only 10.8% of C1 and 8.7% of Cw1 are currently protected. Both vegetation complexes are below the Commonwealth Government’s 30% retention targets and it would be desirable to  at least retain 30% of each vegetation complex of its original pre-European extent. 
C1 is characterised by open to tall forest of Jarrah (Eucalyptus marginata), Marri (Eucalyptus or Corymbia calophylla) and Banksia grandis on lateritic ground while Cw1 is a mixture of open forest and woodland of Karri (Eucalyptus diversicolor), Marri, Jarrah and low woodland of Melaleuca pressiana and Banksia littoralis on depressions. (Webb et al, 2016)

In those descriptions Agonis flexuosa is not mentioned but  in the  creek lines peppermint (Agonis flexuosa), Ti-tree (Taxandria species), Astartea fascicularis, Callystachys lanceolata, Lepidosperma species & rushes/sedges and bracken are the dominant species. 
The majority of the property – Jarrah/Marri and peppermint forest – has an intact, thick and excellent understorey vegetation of: 

Agonis flexuosa (Peppermint tree),  Allocasuarina fraseriana  (Sheoak), Hovea elliptica (Tree hovea), Podocarpus drouyniannus (Emu bush), Taxandria parviceps and T. linearifolia (Tea tree), Xanthorrhoea preissii  and X. gracilis (Balga /Small balga), Lepidosperma squamatum, L. gladiatum and L. tetratequum (Sedge, Sword sedge and Square sedge), Macrozamia reidlei (Zamia), Hakea lissocarpha and H. amplexicaulis (Honeybush and Stem clasping hakea), Patersonia umbrosa (Native flag), Bossiaea linophylla (Weeping bossiaea), Billardiera floribunda, Hibbertia hypericoides and H. cunninghammii (Buttercup),  Astartea fascicularis (Winter astartea), Acacia pulchella, A. subracemosa , A. divergens and A. myrtifolia (Prickly moses, Karri wattle, Shark tooth wattle and Myrtle wattle), Leucopogon parviflorus and L. verticillatus (Heath and Tassel shrub), Pteridium esculentum (Bracken), Mirbelia dilitata (Pink pea), Pimelea rosea and P. spectabilis (Riceflower, Spectacular riceflower), Stylidium species (Trigger plants), Clematis pubescens (Old man’s beard) and Scaevola calliptera (Fan flower )

Established in the 1970s, only very small patches burnt in that period.
The adjacent national park could have added dispersal opportunities and increased security for the released ringtail possums – if the departmental burning regime was not the threatening process, it unfortunately is. (see ‘Fire threat for our projects)

Baiting started in 1978 and is still ongoing. Cat traps are frequently used and baited areas are monitoring by people and cameras.

There was a very small ringtail population of origin that was subsequently increased through releases between 2012 and 2016.
As we can only release very low numbers, we need to keep losses due to predation and stress to a minimum.

Site B
The site has a size of approximately  42 ha with one large (approx. 5 ha) peppermint dominated area. Boundaries are a minor road and otherwise mainly cleared farmland. A long-flowing creek line and a small dam provide almost year-round water.

The vegetation complexes on this property are within the Warren Biogeographical region and the WAR02 sub-region within the South-west. 

About half the area belongs to the  Wilyabrup W1 vegetation complex, which is described as tall open forest of Karri, Marri, Sheoak and WA Peppermint on deeply incised valleys. The protected areas containing this complex are below the Commonwealth Government’s 30% retention requirements.

Most of the remaining area belongs to the Wilyabrup Ww1 vegetation complex, described as tall open forest of Karri, WA Peppermint,  Sheoak with some Marri on flats and valleys and is again under the Commonwealth Government’s 30% retention requirements.
A small area of the Cowaramup C1 vegetation complex open to tall open forest of Jarrah, Marri, Banksia on lateritic uplands is severely under the Commonwealth Government’s 30% retention requirements. (Webb et al, 2016)

Karri forest with dense understorey and most of the Jarrah, Marri, Sheoak and Banksia woodlands and forest are in excellent condition and would provide linkages and support for ringtail possum but have limited habitat values. The peppermint woodland is of high value to ringtails but has only sparse understorey as it was burnt frequently. The creekline system is dominated  by peppermint trees and an understorey of Taxandria species (Ti-trees), Lepidosperma species (sedges), Callystachys lanceolata (Wonnich) and Pteridium esculentum (bracken), which remained unburnt for several decades.

Baiting for foxes and cat trapping is conducted intermittendly.
There was a very small – possibly transient – ringtail population of origin which was increased through releases from late 2014 to late 2015.

Site C
The approximately 70 ha large site is bounded by national park, a secondary road, neighbouring smaller farm and bush lots. The variation in elevation is severe– low dam and creek line, rocky underground with large boulders in higher areas. 

The main vegetation complexes are Wilyabrup W1 and Cowaramup C1 with only a small area of the vegetation complex Wilyabrup Ww1. All are in very good condition.

Peppermint-dominated  areas that are of the highest value to ringtail possums have very sparse understorey and even the creekline system  would therefore be classified as fairly degraded. This might have resulted from former stock grazing. The creekline system has not been burnt for a long time.  Apart from weedy understorey, there are some remnants of ti-trees, sedges, melaleucas and bracken. Lots of peppermint seedlings are however regenerating and could provide further good ringtail habitat in a few decades.

However , there is also an area with an intact ecosystem of Taxandria species, Astartea fascicularis, Callystachys lanceolata, Lepidosperma sedges and Pteridium esculentum (bracken) which should be good habitat for ringtail possums. 

There was a small exiting population (at least one breeding couple) in the lower creekline area. Our release activities (starting in late 2016) therefore concentrated mainly on other areas.