Threatened Species Strategy Year 3 Scorecard – Regent Honeyeater
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Threatened Species Strategy – Year 3 Priority Species Scorecard (2018) Regent Honeyeater Anthochaera phrygia Key Findings Regent Honeyeaters once ranged abundantly from Adelaide to south- east Queensland, however much of the species’ habitat was cleared for agriculture and the severely declined population of Regent Honeyeaters now moves between widely spaced patches of remnant habitat. Recovery actions including habitat protection, restoration and revegetation at key habitat sites and the release of captive bred birds have helped slow the rate of decline, however numbers continue to fall. Photo: Dean Ingwersen Significant trajectory change from 2005-15 to 2015-18? Yes, decline ongoing but at a slower rate. Priority future actions • Continue captive releases • Active nest protection from predators and competitors at multiple sites • Augment food at critical times during breeding cycle • Protect all known breeding habitat Full assessment information Background information 2018 population trajectory assessment 1. Conservation status and taxonomy 8. Expert elicitation for population trends 2. Conservation history and prospects 9. Immediate priorities from 2019 3. Past and current trends 10. Contributors 4. Key threats 11. Legislative documents 5. Past and current management 12. References 6. Support from the Australian Government 13. Citation 7. Measuring progress towards conservation 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 (2016), 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: IUCN Critically Endangered Monotypic: no infraspecific taxa described. EPBC Critically Endangered ACT Endangered NSW Critically Endangered QLD Endangered SA Endangered VIC Threatened 2. Conservation history and prospects The Regent Honeyeater is endemic to mainland south-east Australia. Formerly abundant and ranging from Adelaide to south-east Queensland, the species now has a patchy distribution which extends from south east Queensland, through New South Wales (NSW) and the Australian Capital Territory (ACT), to central Victoria. It is highly mobile, occurring only irregularly in most sites, and in variable numbers. Commonly associated with box ironbark eucalypt woodland and dry sclerophyll forest, it also inhabits riparian vegetation and lowland coastal forest and a range of other habitats. The species has declined rapidly since the 1960s (Franklin et al. 1989). While extensive clearing of its preferred box–gum– ironbark woodland habitats were a major driver of declines, contemporary reasons for its decline are poorly understood (Clarke et al. 2003, Crates et al. 2017). Recent research suggests that high nest failure rates are unsustainable in both wild (Crates et al. 2018) and captive released birds (Taylor et al. 2018). 3. Past and current trends The Regent Honeyeater was formerly distributed throughout the temperate woodlands and forests in south-eastern Australia, from the Adelaide region, South Australia (SA), to 100km north of Brisbane, Qld. Today it rarely visits the Gore-Karara region south of Brisbane and no longer occurs in SA. The species’ distribution is now extremely patchy with a small number of known breeding sites. In 1995 nearly 1500 were recorded and 1,350 in 1997 but numbers dropped precipitously after that – highest totals were 659 in 2000, 631 in 2002 and 449 in 2005 (D. Ingwersen pers. comm.). By 2010 the total population size was estimated at 350-400 mature individuals (Kvistad et al. 2015). Low breeding success and a male-biased sex ratio suggest this number may be lower (Crates et al. 2018a). The average number of birds seen per year over the last decade is 136 (D. Ingwersen pers. comm.) (see below for a breakdown of the raw yearly counts). While the wild population has been augmented by substantial releases of captive bred birds, their nesting success is about half that of wild-raised birds (Taylor et al. 2018). 2 Information current to December 2018 Threatened Species Strategy – Year 3 Priority Species Scorecard (2018) Year 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 Count 117 100 124 271 110 69 137 141 201 85 Monitoring (existing programs): Volunteer surveys have been conducted twice a year, in May and August, since 1995, involving hundreds of volunteers and community groups. Detailed studies are also undertaken with respect to recently released birds, and the Australian National University has recently monitored about a quarter of the population during the nesting season (Crates et al. 2017). Population trends: Tables 1 and 2 summarise the overall trend and status of the Regent Honeyeater. 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 Regent Honeyeater distribution and population size, and (where possible) trend estimates between 2015 and 2018 for each parameter. Confidence in Population parameters Published baseline 2015 estimate 2018 estimate estimates WILD Extent of Occurrence 600,000 km2 600,000 km2 600,000 km2 High Area of Occupancy 300 km2 300 km2 300 km2 High Dates of records and As per Bird Action Plan methods used No. mature individuals 350 350 350 Medium Any other measure of n/a n/a n/a n/a relative abundance No. of subpopulations 1 1 1 High No. of locations >10 >10 >10 High High: based on recent global Generation time 3.4 n/a n/a modelling by BirdLife International CAPTIVE BREEDING No. mature individuals 50 50 50 High No. locations 2 6 6*# High *From http://www.geckodan.com/wp-content/uploads/2017/12/Regent-Honeyeater-.pdf # New breeding facilities being constructed at Western Plains Zoo (Dubbo) to increase captive population and mitigate risk. 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 Regent Honeyeater Est. % of Confidence in Confidence in 2005-2015 2015-2018 Sub-population total pop’n 2005-2015 2015-2018 Details trend trend (pre-2015) trend trend Numbers in the wild may Whole be sustained by birds 100 Medium N/a population ? released from captivity but not yet known. 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 (2016) 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. Habitat loss and degradation Ongoing clearing of woodland and forest containing the key eucalypt species preferred by Regent Honeyeaters exacerbates extensive historical clearance, reducing the available nesting and foraging habitat to small remnants of what previously existed. These remnants are continuing to decline in area through residential, agricultural and industrial developments and face ongoing degradation and loss of quality through loss of mature trees (which occurs through senescence), eucalypt dieback, harvesting for fence posts or firewood, and/or drought induced stress. Noisy Miner (Manorina melanocephala) Noisy Miners are favoured by landscape fragmentation and aggressively exclude other species. They are also now known to be an important predator of Regent Honeyeater nests (Collins, in Higgins et al. 2001; Crates et al. 2018). Drought Extended dry weather reduces the number of sites where high quality food may be found in the landscape by suppressing flowering events in key Eucalypt species. Nest predation Recent reports of predation of Regent Honeyeater nests by Brush-tail Possums (Trichosurus vulpecula), Sugar (Petaurus brevipes) and Squirrel Gliders (Petaurus norfolcensis), Pied Currawongs (Strepera graculina), Australian Ravens (Corvus coronoides) and Pied Butcherbirds suggests nest predation by a range of species is more important to honeyeater demography than previously appreciated (Crates et al. 2018, Taylor et al. 2018). 4 Information current to December 2018 Threatened Species Strategy – Year 3 Priority Species Scorecard (2018) Small population size The small population is spread across such a large area of south-eastern Australia that the inherent issues related to small population