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Carnaby’s Black-Cockatoo is an endangered species, with less than 50% of the original population remaining (Garnett and Crowley 2000). A major threatening process includes habitat fragmentation and the removal of critical feeding resources (Cale 2003). The GSS study area in an important foraging area during the non-breeding season for Carnaby’s Black-Cockatoo. Both native banksia woodlands and pine plantations have been recognised as an important food resource (Perry 1948; Saunders 1974b; Saunders 1980). Expanding urban populations and agricultural development has resulted in the removal of approximately 50% of native vegetation in the GSS study area. Within the remnant vegetation, the energetics, occurrence and densities of principal native food sources (e.g. Banksia attenuata) is still largely unknown, but varies depending on soil type, vegetation complex and fire history (Heddle et al. 1980; Scott and Black 1981; Valentine and Stock unpublished data). In addition, there are a number of limitations with the existing data, and further research is required to accurately estimate the availability of food resources. The predicted removal without replacement of the pine plantations is expected to impact on Carnaby’s Black-Cockatoo (Cale 2003; Garnett and Crowley 2000). The amount of food resources in the GSS pine plantations currently available to Carnaby’s Black- Cockatoo is predicted to be able to support over 10,000 birds for a 6 month period (with a prior mentioned caveats). If preliminary foraging behaviour data is incorporated, it is likely that the pine plantation will support approximately 2,800 birds for a 6 month period. Food resources in remnant Banksia attenuata habitat in the GSS study area vary depending on the landform and year since last burn (Valentine and Stock, unpublished data). The combined area of Bassendean North and Cottesloe North vegetation complexes (~ 25,000 ha) within DEC estate in the GSS study area could provide the minimum requirement of

Where threatened species persist in multiple use landscapes, management activities, such as prescribed burning, may influence the availability of resources for those species. We examined how time since fire can influence food resources for the endangered Carnaby's cockatoo (Calyptorhynchus latirostris) in banksia woodlands of southwestern Australia. Tree density and cone productivity of dominant plant species, Banksia attenuata and Banksia menziesii, were compared across 44 sites of varying post-fire aged vegetation. The number of Carnaby's cockatoos that could be supported in banksia woodlands was estimated using the bird's energetic requirements and seed energy content. Banksia attenuata produced more cones at sites aged 10-30. years since fire in both survey years, while cone productivity for B. menziesii was highest in very old sites (>35. years since fire) in one year only. Higher numbers of Carnaby's cockatoos were predicted to be supported in vegetation aged between 14-30. years since fire, peaking in vegetation aged 20-25. years. The current distribution of post-fire aged vegetation within this area (>60% burnt within the last 7. years) is predicted to support ~2725 Carnaby's cockatoos, representing 25-35% of the estimated birds reliant on the area. Our results indicate that food resources are influenced by time since fire and, consequently, if optimising food resources was an objective, may be manipulated by altering burning patterns. While human and asset protection is a priority for prescribed burning, management of landscapes for improved persistence of threatened species is also important and complex trade-offs will have to be considered.

A decline in the condition of forests and woodlands is a worldwide phenomenon. In the south west of Western Australia, declines of Eucalyptus wandoo have been noted since the 1980s and more recently in the 2000s. There is a knowledge gap regarding the relationship between the effects of tree decline and wildlife. This study aimed to help close this knowledge gap and provide insight to the effects of tree decline on fauna. At two reserves in Western Australia (Dryandra Woodland and Wandoo Conservation Park) 24 sites of pure E. wandoo stands were used to investigate this relationship. Firstly, on-ground and remotely sensed methods of canopy assessment in E. wandoo were compared. The open canopy of E. wandoo, the spatial heterogeneity and cyclic decline, as well as the expression of recovery symptoms (e.g. epicormic growth) has meant that remote sensing methods are limited in their ability to reflect the on-ground changes noted and were not used in the following chapters. Reptiles, mammals, birds, vertebrate foraging activities and reproductive efforts of E. wandoo were related to E. wandoo condition and the changes in the surrounding habitat. Healthier patches of E. wandoo that were longer unburnt with higher levels of site litter had more reptile species and higher abundances. Site litter cover, crown dieback, understorey vegetation cover and tree density influenced the abundance and species richness of small mammals. Three focal bird species weebills (Smicrornis brevirostris), rufous tree creepers (Climacteris rufa) and yellow-plumed honeyeaters (Lichenostomus ornatus) were influenced by E. wandoo condition according to their individual ecology. Vertebrate activities and the tree and habitat characteristics were related, with more diggings and scats present underneath healthier E. wandoo trees. Lastly, E. wandoo condition, weather, time since last fire and tree size were factors related to the reproductive cycle of E. wandoo trees from this study. Eucalyptus wandoo

One of the few commonly occuring species of digging marsupial in south-western Australia is the subspecies of southern brown bandicoot (Isoodon obesulus fusciventor). Unlike a large proportion of Australian digging marsupials that have suffered attrition, bandicoots have persisted and shown resilience to human-mediated disturbance in peri-urban regions. This thesis evaluates some of the ecological roles of bandicoots in ecosystem processes in degraded Eucalyptus gomphocephala woodland in Yalgorup National Park. Bandicoots forage for the fruiting bodies of mycorrhizal fungi and other subterranean food and in doing so make small pits in the soil surface. Surveys of these foraging pits over a six month period revealed they are sites of lower soil hydrophobicity and higher soil moisture compared to the surrounding undisturbed soil. Additionally, the foraging pits and the area immediately surrounding them collect more leaf litter than the surrounding areas. The impact of foraging pits on ant-seed removal rates was explored by creating artificial diggings. Three local seed species Acacia saligna, Eucalyptus gomphocephala, and Kennedia prostrata were used in a cafeteria style experiment. Results found artificially created diggings had no effect on seed removal rates and that E. gomphocephala had the highest seed removal rate. This study suggests that bandicoots provide an important source of soil surface heterogeneity, contributing to ecosystem processes. Their presence in the landscape has the potential to contribute to the restoration of degraded ecosystems.

This study examined the behavioural ecology of Carnaby‘s Black-Cockatoo in the Gnangara Sustainability Strategy study area, with a focus on habitat use of pine plantations. The study confirms that the pine is the main food source for Carnaby‘s Black-Cockatoos within the GSS area during the non-breeding season (January-June). The value of the Gnangara-Pinjar-Yanchep pine plantations as a food source for Carnaby‘s Black-Cockatoo should not be underestimated. Large congregations of birds (~3000) utilised the pine plantations for an extended period, mainly January-March but with birds continuing to feeding within the plantations through June. The pine plantations have provided an important and dependable feeding habitat since the 1940s, a period that has seen the abundance of this species decline by at least 50% and its range contract by one-third. The impact of pine removal should also be considered within a suite of broader changes to the GSS landscape. These changes include the loss of feeding habitats off-plantation (e.g. thickets of Banksia sessilis around Neerabup and within the Northwest Corridor) and predictions of declining productivity within areas of Banksia woodland due to reduced rainfall and the spread of dieback, Phytophthora cinnamomi. There is uncertainty about whether the remnant native vegetation in the GSS area will provide an adequate food source following the removal of pine plantations, particularly from January to March when feeding within the plantations is most intensive. This topic requires further investigation. In April and May 2009 (‗dryandra period), at least 4000 birds were concentrated between Neerabup and Boongarra as large aggregations form to feed within thickets of Banksia sessilis. These aggregations probably draw together flocks that through February and March had been feeding: (a) in and around the GSS pine plantations; (b) in the suburban areas to the south and west of the plantations; and (c) in areas to the north of Boongarra.

Hopkins, A. J. M., Tay, N. E., Bryant, G. L., Ruthrof, K. X., Valentine, L. E., Kobryn, H., . . . Fleming, P. A. (2021). Urban remnant size alters fungal functional groups dispersed by a digging mammal. Biodiversity and Conservation, 30(13), 3983-4003. https://doi.org/10.1007/s10531-021-02287-4

Ritchie, A. L., Svejcar, L. N., Ayre, B. M., Bolleter, J., Brace, A., Craig, M. D., … Hobbs, R. J. (2021). A threatened ecological community: Research advances and priorities for banksia woodlands. Australian Journal of Botany, 69(2), 53-84. https://doi.org/10.1071/BT20089

Davis R.A., Valentine L.E., Craig M.D., Wilson B., Bancroft W.J., Mallie M. (2014). Impact of Phytophthora-dieback on birds in Banksia woodlands in south west Western Australia. Biological Conservation, 171, 136-144. Available here