Threatened Species Strategy – Year 3 Priority Species Scorecard (2018) Red-tailed Black-Cockatoo (south-eastern) Calyptorhynchus banksia graptogyne Key Findings South-eastern Red-tailed Black Cockatoos are highly dependent on seeds from just three tree species, as well as deep hollows in very old eucalypt trees for nesting. Habitat loss through tree decline has been caused by drying climatic changes and fire disturbance. Significant recovery efforts have focused on habitat protection and regeneration, however numbers of young birds joining the population are falling for reasons that are unclear. Photo: Bob McPherson Significant trajectory change from 2005-15 to 2015-18? No, ongoing slow decline. Priority future actions • Identify causes of low fecundity in breeding birds and low seed set in monitored trees • All important trees effectively protected against fire, clearing of habitat strictly forbidden • Known nest trees maintained, additional nest boxes erected near high quality feeding trees • A drought strategy developed and implemented Full assessment information Background information 2018 population trajectory assessment 1. Conservation status and taxonomy 8. Expert elicitation for population 2. Conservation history and prospects trends 3. Past and current trends 9. Immediate priorities from 2019 4. Key threats 10. Contributors 5. Past and current management 11. Legislative documents 6. Support from the Australian Government 12. References 7. Measuring progress towards conservation 13. Citation The primary purpose of this scorecard is to assess progress against the year three targets outlined in the Australian Government’s Threatened Species Strategy, including estimating the change in population trajectory of 20 bird species. It has been prepared by experts from the National Environmental Science Program’s Threatened Species Recovery Hub, with input from a number of taxon experts, a range of stakeholders and staff from the Office of the Threatened Species Commissioner, for the information of the Australian Government and is non-statutory. It has been informed by statutory planning documents that guide recovery of the species, such as Recovery Plans and/or Conservation Advices (see Section 11). The descriptive information in this scorecard is drawn from Commonwealth of Australia (2007), unless otherwise noted by additional citations. The background information aims to provide context for estimation of progress in research and management (Section 7) and estimation of population size and trajectories (Section 8). 1 Information current to December 2018 Threatened Species Strategy – Year 3 Priority Species Scorecard (2018) 1. Conservation status and taxonomy Conservation status 2018 Taxonomy: Five subspecies of Red-tailed Black-Cockatoo IUCN Endangered Calyptorhynchus banksii are recognised. EPBC Endangered Calyptorhynchus banksii naso (south-west Western Australia) is listed as Vulnerable, the SA Endangered remainder are not listed. VIC Threatened 2. Conservation history and prospects The south-eastern subspecies of Red-tailed Black-cockatoo is confined to an area of about 18,000 km2 in south-eastern South Australia and adjacent far south-western Victoria. A single population of about 1400 individuals persists, despite reduced feeding and nesting habitat. The cockatoo feeds almost entirely on the seeds of three tree species, all of which must be mature before they produce seed; brown stringybark (Eucalyptus baxteri), desert stringybark (Eucalyptus arenacea) and buloke (Allocasuarina luehmannii). Fire has a major impact on food quantity, setting stringybark trees back 10 years before they produce seed crops similar in size to long-unburnt trees. Nesting habitat may also limit populations in the future as big hollows take centuries to form and an estimated 4-7% have been lost annually, suggesting that there may already be a serious shortfall in suitable hollow-bearing trees, manifest initially through increased competition with other hollow-nesters. Despite this there has been great progress in developing support for the birds with numerous local people involved in counting the cockatoos, rehabilitating landscapes and protecting nest trees (Russell et al. 2018). This is likely because of the attention paid to the bird’s annual population counts, which, though variable, have been fairly steady. However, recent measurements of seed availability and low fecundity are cause for concern, especially as the underlying causes are not fully understood (R.Hill in litt.) and counts since 2015, a record year, have been substantially lower than previously. 3. Past and current trends Counts since 1996 of the minimum number of Red-tailed Black-Cockatoos alive have varied greatly from year to year and no obvious trend has emerged, with the population currently between 1000 and 2000 individuals. However, in the last few years, there has been a substantial increase in the proportion of adult males, with clear red tail panels, over females/immatures, with barred tail panels suggesting either an increase in female mortality or, more likely, a decrease in breeding success and lower recruitment. Mean proportion of adult males in flocks since 1998 is 42%. However in 2016 and again in 2018 the ratio of barred to red-tailed birds was almost at parity (R.Hill in litt.). 2 Information current to December 2018 Threatened Species Strategy – Year 3 Priority Species Scorecard (2018) Monitoring (existing programs): Annual counts have been conducted by birdwatchers since 1996 (organised by the recovery team and BirdLife Australia) that determine the minimum known to be alive. Monitoring was funded initially by the Commonwealth National Landcare Program and has had contributions from SENRM, GHCMA and WCMA. Since 1998 the project officer has collected flock count ratios to determine recruitment and gender ratios as well as assess stringybark capsule availability at 300 marked trees from 10 sites across the subspecies range. Both project officer projects have been funded by DELWP in addition to the groups above. Population trends: Tables 1 and 2 summarise the overall trend and status of the Red-tailed Black Cockatoo. The information provided in these tables is derived from the recovery plan and conservation advices with some amendments made by contributing experts based on new information. Table 1. Summary of the available information on south-eastern Red-tailed Black-Cockatoo distribution and population size, and (where possible) trend estimates between 2015 and 2018 for each parameter. Published Confidence in Population parameters 2015 Estimate 2018 Estimate baseline estimates WILD* Extent of Occurrence 23,000 km2 23,000 km2 23,000 km2 High Area of Occupancy 1300 km2 1300 km2 1300 km2 High Dates of records and methods used As per Bird Action Plan No. mature individuals 1100 1000-2000 1000-2000 Low Ratio of all barred Any other measure of relative 1998: 63% 2018: 52% birds in flocks in High abundance (specify) autumn. No. of subpopulations 1 1 1 High No. of locations >10 >10 >10 High High; based on BirdLife Generation time 10.4 n/a n/a International global modelling *Including translocations 3 Information current to December 2018 Threatened Species Strategy – Year 3 Priority Species Scorecard (2018) Table 2. Estimated recent (2005-2015) and current (2015-2018) population trends for the south- eastern Red-tailed Black-Cockatoo. Est. % of 2005- Confidence 2015- Confidence Sub- total in in 2015 2018 Details population pop’n 2005-2015 2015-2018 trend trend trend trend Annual counts, though variable, do not Whole suggest decline but recent low fecundity 100 High Medium population and low seed availability suggest a decline in population and habitat health. KEY: Improving Stable Deteriorating Unknown Confidence Description High Trend documented Medium Trend considered likely based on documentation ? Low Trend suspected but evidence indirect or equivocal 4. Key threats The threats listed here are derived from the Commonwealth of Australia (2007) with some amendments from contributing experts based on new information. Note that this is not a list of all plausible threats, but a subset of the threats that are likely to have the largest impact on populations. Increase in fire frequency/intensity Food shortages are the main threat to the long-term survival of the south-eastern Red-tailed Black- Cockatoo. Strong cyclic variation in seed availability has been exacerbated by the loss and degradation of feeding habitat: dietary specialisation and food shortages have a profound effect on the birds’ annual distribution, movements, and nesting success. Prescribed burns and wildfires substantially reduce seed availability in stringybarks for at least nine years, with some effects persisting for more than 11 years (Koch 2003). Nearly 70% of all stringybark habitats are on public land in Victoria. About half of the stringybark in areas burnt less than 9 years ago are in priority fuel-reduction areas, where the aim is to control the spread of wildfire (meaning there is little opportunity to reduce fire frequency (Russell et al. 2018). Even where there are aspirations to protect habitat from fire, on catastrophic fire danger days all fire-fighting resources are likely to be directed at protecting life and property. Agro-industry farming About 57% of all suitable habitat has been cleared within the range: 87% of original stringybark habitat in SA, 42% in Vic. While clearing of large forest blocks has largely ceased, the loss of isolated trees in paddocks continues, particularly