Twelve Years of Winter Counts of the Orange-Bellied Parrot Neophema Chrysogaster

VOL. 14 (8) DECEMBER 1992 305 AUSTRALIAN BIRD WATCHER 1992, 14, 305-312 Twelve Years of Winter Counts of the Orange-bellied Parrot Neophema chrysogaster by JONATHAN STARKS1, PETER BROWN2 , RICHARD LOYN3 and PETER MENKHORSP 1Royal Australasian Ornithologists Union, 21 Gladstone Street, Moonee Ponds, Victoria 3039 2Department of Parks, Wildlife and Heritage, 134 Macquarie Street, Hobart, Tasmania 7000 3Wildlife Branch, Department of Conservation and Environment, P. 0. Box 137, Heidelberg, Victoria 3084 Summary Orange-bellied Parrots Neophema chrysogaster were counted annually in late July from 1979 to 1990 in southern Victoria and south-eastern South Australia. The minimum total winter population averaged 83.9 birds (range 67-126), with no significant change in numbers over the 12 years. The main wintering areas were Point Wilson, Lake Connewarre and Swan Island in Victoria, and Carpenter Rocks in South Australia. The counts were made possible only by the dedication of teams of volunteers. Introduction In recent years, the status of the critically endangered Orange-bellied Parrot Neophema chrysogaster has been the subject of much attention in Australia. More than 70 years ago, Mathews (1917) was concerned for the plight of the species, but 50 years passed before Jarman (1965) comprehensively summarised its status and established just how rare it was. In 1978, the first positive steps to conserve the species were taken. In that year studies were initiated by ICI (Australia) who had acquired land and proposed to build a petrochemical complex at Point Wilson adjacent to one of the bird's major overwintering locations. Plans for this complex have since been shelved. The results of these studies were published in a series of reports and have been summarised in Loyn et aL (1986). Included in the ICI study was a survey of saltmarsh in Victoria which produced maps of saltmarsh communities (Carr & Kinhill Planners 1979). The ecology of the parrot at Point Wilson was described by Loyn et aL (1986). In 1979, a two-year study of the species was funded by World Wildlife Fund (Australia) - its first project. Reports were published on this work (Brown & Wilson 1980, 1981) and in 1984 a plan to conserve the species was produced (Brown & Wilson 1984). This was the first substantial management plan for an Australian endangered species. The plan continues to be implemented by the three States in which the parrot occurs (Menkhorst et aL 1990). The continued support of the Australian National Parks and Wildlife Service, the State Governments of South Australia, Tasmania and Victoria, the Royal Australasian Ornithologists Union (RAOU), the Bird Observers Club of Australia and the International Council for Bird Preservation has been vitaL Research programs and management initiatives are reviewed by the Orange-bellied Parrot Recovery Team, which meets annually. This paper summarises some of the information obtained, and presents results of counts from 1979 to 1990. Habits and habitat Orange-bellied Parrots breed in south-west Tasmania along a coastal strip of AUSTRALIAN 306 STARKS, BROWN, LOYN & MENKHORST BIRD WATCHER sedgeland and forest patches between South West Cape and Macquarie Harbour (Brown & Wilson 1980). They arrive at their breeding grounds in October and egg laying begins in mid November. The young fledge in January and February and congregate in flocks on the sedgelands, remaining in the area until mid-late March. Adults depart in late February to early March. The parrots migrate up the west coast of Tasmania, through the western Bass Strait islands and across to the mainland. The last juveniles do not leave Tasmania until about the third week in April. The majority of parrots probably migrate through King Island. Some birds may remain on King Island until late May. Orange-bellied Parrots are very mobile and capable of flying long distances. Flocks in excess of 70 birds have been recorded occasionally but the birds are often well dispersed as small groups of fewer than 30 birds and usually fewer than 10. Flocks usually remain separate from those of other species, but individuals or small groups will sometimes feed with Blue-winged Parrots Neophema chrysostoma, or occasionally other seed-eating birds such as European Goldfinch Carduelis carduelis and House Sparrow Passer domesticus. During winter the birds are usually found within 3 km of the coast but occasionally farther inland in saltmarshes bordering large lakes or on islands in estuaries and drains. In Victoria, the most regular feeding habitat is saltmarsh where the seeds of Beaded Glasswort Sarcocornia quinqueflora, Shrubby Glasswort Sclerostegia arbuscula and several other associated saltmarsh plants are eaten (Loyn et al. 1986). The three main wintering sites in Victoria are Point Wilson, Lake Connewarre and Swan Island. In South Australia, the birds are often found in coastal dune vegetation where they eat the seeds of Sea Rocket Cakile maritima and Bidgee-widgee Acaena novaezelandiae, but also feed on saltmarshes similar to those in Victoria. Orange-bellied Parrots spend most of the day foraging on the ground or in low shrubs, and they are readily disturbed. They usually take off when the observer is about 20-50 metres away, emitting a very distinctive, harsh buzzing alarm call which is rapidly repeated 10 or more times as they rise. In normal flight the call is a single sharp tzit given every 2 or 3 seconds. The musical tinkling alarm call of the Blue winged Parrot is quite different, and the flight call has two or three syllables. Favoured habitats have a number of common features in addition to availability of food plants. They often contain islands or spits with a varied topography which may provide protection from predators. The parrots are often found in luxuriant stands of saltmarsh that remain dry within a flooded area and they avoid feeding in flooded saltmarsh. Fresh water is often available in the form of channels, lake shores or rainwater pools, though the parrots also take dew from vegetation (Loyn et al. 1Q86; Hewish & Starks 1988). Saltmarsh vegetation appears to provide a larger crop of seed when young than old (G. Carr pers. comm.), and the parrots may favour stands that have regenerated recently after disturbance. Excessive disturbance (e.g. overgrazing) can lead to denudation and obvious habitat loss. At Lake Connewarre, the most favoured stands appear to be those that have established recently as the delta islands expand by sedimentation (Hewish & Starks 1988). Counting It is important to know the size of the population and where it occurs. Annual counts of the whole population of Orange-bellied Parrots are the best available measure to record the effectiveness of actions taken to conserve the species. Counts in the breeding season are not practical as the population is widely dispersed and difficult to locate in the rugged terrain. The most reliable method is to conduct simultaneous counts in winter when the birds congregate on beach-fronts and coastal saltmarshes. VOL. 14 (8) DECEMBER 1992 Orange-bellied Parrot Counts 307 An enormous area of potentially suitable habitat is searched annually, from the Gippsland Lakes in eastern Victoria to Lake Alexandrina in South Australia. Annual winter counts and searches have been carried out since 1978. To search all the potential habitat within their winter range on a single weekend, hundreds of kilometres of beaches and many square kilometres of saltmarsh need to be visited. The counts have involved hundreds of dedicated volunteers, without whom satisfactory results could not have been achieved. Intrepid observers have often had to cope with very swampy ground, thick mud and foul weather with no available shelter. The extensive saltmarshes are often fairly devoid of birds, though the list of incidental sightings is impressive, including Lewin's Rail Rallus pectoralis, Ground Parrot Pezoporus wallicus, and even White Goshawk Accipiter novaehollandiae. Grateful thanks are due to all those helpers who persevered. The early counts, co-ordinated by Richard Loyn and Brett Lane (1978-1982), were funded by ICI Australia and the results published in a series of ICI reports (Loyn & Kinhill Planners 1979a,b; Lane et a!. 1980). Since 1983, the counts have been financed by the Wildlife Branch, Department of Conservation and Environment, Victoria. Since 1984, the counts have been co-ordinated by the RAOU under contract to the Wildlife Branch. Organisers have been Peter Menkhorst (1983), Tim Reid (1984), Angela Jessop (1985) and Jonathan Starks (1986-present). Reports of the results have been produced (Menkhorst 1984; Jessop & Reid 1986; Starks 1988, 1992). During the first year of surveys in Victoria (1978), searches were made at various times during the winter in Western Port (including French Island), the west side of Port Phillip Bay (Altona to Pt Cook, Pt Wilson, Pt Henry, Mud Islands and the Bellarine Peninsula) and along the coast near Port Fairy. Parts of south-eastern South Australia were visited in September, including Beachport, Robe and parts of the Coorong. King Island was also searched in September. In 1979, further efforts were made to co-ordinate simultaneous counts. A team of observers was organised to search all potentially suitable habitat throughout Victoria, South Australia and parts of Tasmania. Counts were made on 3 June and 12 August and people were also encouraged to search for Orange-bellied Parrots at any time between March and October. By 1980, the third or fourth weekend in July (between 22 and 29 July) had been chosen as the most suitable weekend to conduct simultaneous annual counts as the birds were thought to be less mobile than at other times during the winter. In order to determine if the birds moved between sites, counts were also made in the last week of May and the first week in September from 1983 to 1987. After 1987, these counts were discontinued as birds proved too difficult to locate, particularly in September, and the results did not justify the amount of effort put into the searches.

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