Australian Bird Reintroductions
Black-eared Miner
A healthy population of the endangered Black-eared Miner (BEM) exists in the Bookmark Biosphere Reserve, South Australia, covering an area just under 400,000 ha. The potential scale and severity of wildfires in the mallee habitat means this single population is at risk of extinction, or at the least severe depletion, from a single wildfire. To establish a second population, 4 colonies (30, 10, 12, 17 birds) where translocated during September-November 2000 to the Murray Sunset National Park (633,000 ha), Victoria. This area once supported colonies of BEM but colonies became isolated through habitat clearing, uncontrolled wildfires and fuel reduction burns. Areas of the park containing mallee of suitable age (40+ years) for BEM were identified. While these areas are not extensive, additional large tracts of mallee will reach an appropriate age within the next 10 years. Two hard and two soft releases were trialed, both proving successful. In total 59 adults and 10 fledglings were moved, with only one fledgling lost during its week housed in the aviary. Radio-transmitters were attached to 5 birds in each colony, with a plane on standby. However the miners surprised everyone by staying at their release sites for the life of the transmitters. Incredibly, the first hard-released colony starting building nests only 10 days after their release, subsequently producing 2 fledglings. One soft-release colony returned 7 weeks after their release and started building 80m from the aviary. The outcome of these nesting attempts is unknown. Colour band sightings revealed at least 75% adult survival after a month. Interaction between translocated and existing colonies has already been witnessed with unbanded birds joining translocated birds and a banded juvenile moving colony. A further 4 colonies will be translocated during the next breeding season. Contact Mike Clarke.
Regent Honeyeater
Captive-bred regent honeyeaters have been released at Chiltern, Victoria, to supplement the declining population there. Although a range of management initiatives have been undertaken in Victoria with the aim of stopping the decline, supplementation is viewed as a necessary short-term fix to maintain the population, and birds were available from the now well-established captive breeding programme. The 27 birds were met at Albury airport and driven to Chiltern on 28 April 2008, and half the birds released on 1 May and the other half on 3 May. All birds carried radio transmitters, and 20 of the 27 birds were still being seen on an almost daily basis two months after release. Most of the birds were near the release site at that stage, probably due to flowering of Mugga/Grey Box hybrids in the area at that time, but had explored widely over the 4520 ha national park and surrounding farmland, and had also interacted with birds from the remnant regent honeyeater population. Contact David Geering.
Southern Emu-wren
The critically endangered Mount Lofty Ranges Southern Emu-wren (Stipiturus malachurus intermedius) has been reintroduced to an area from which it was extirpated by wildfire almost 20 years ago. In July 2001, 30 emu-wrens (15 male, 15 female) were transferred from Deep Creek Conservation Park 50 km NE to Cox Scrub Conservation Park (540 ha), 50 km SSE of Adelaide. A further 16 were translocated in 2002. Southern Emu-wrens occurred in Cox Scrub Conservation Park until the fire burnt out the park in 1983, but being isolated from the nearest subpopulations, the park was not recolonised. Emu-wrens have short, rounded wings and cannot undertake sustained flight, and as such have very limited dispersal capabilities. The source population in Deep Creek Conservation Park is the largest known subpopulation of the subspecies, with at least several hundred individuals. Emu-wrens were trapped over several weeks, mostly as pairs, using mist-nets and pre-recorded calls to facilitate trapping, and transferred to the release site by road, generally on the day of capture. Monitoring during the first spring–summer breeding season revealed establishment of at least 8 breeding pairs and successful reproduction, with at least 10 young produced. Monitoring during the second breeding season revealed up to 14 pairs, persistence of several founder-group pairs formed during the 2001–2002 breeding season and further successful reproduction including breeding by some founder-group progeny. At least 13–16 fully-grown young were produced in 2002–2003. Emu-wrens are small (~ 7g), secretive birds that can hardly fly. Radio tracking is not feasible, so monitoring involves fairly arduous transect and area search methods in dense scrub, meaning that the population is probably larger than the number of birds detected.The project is funded primarily by the Commonwealth Government Endangered Species Program and S.A. Government Department for Environment and Heritage. The Conservation Council of S.A. administers the recovery program. Contact Marcus Pickett.
Eastern Bristlebird
The eastern bristlebird (Dasyornis brachypterus) is an endangered Australian passerine which is restricted to a few isolated populations. It has poor dispersal ability as it is semi-flightless. It is threatened by habitat loss and fragmentation, inappropriate fire regimes and introduced predators. Reintroduction was identified as a potential strategy to help reduce risks to the species from threats such as widespread intensive fire. Bristlebirds were sourced on Bherwerre Peninsula, Jervis Bay, NSW, one of the largest remaining populations. The release site was on Beecroft Peninsula, only 12 km away and considered to be part of the former range of the species. Previous threats to bristlebirds are now being managed in the release site. In three field seasons over three years, 15 (2003), 20 (2004) and 15 (2005) bristlebirds were caught from the wild, transported to the release location and immediately released. Twenty females and 28 males were released. At the time of writing, the reintroduction was a success. Bristlebirds were calling within days of release and have remained in the release environment for up to four years. Two unbanded bristlebirds were observed in 2005 indicating some breeding has occurred. A minimum of 21 bristlebirds were recorded in the release environment in 2006. The removal of bristlebirds over three years from a limited area in the source population had no detectable impact. Contact David Bain, Institute for Conservation Biology and Law, University of Wollongong.