VOL. 19 (6-7) JUNE-SEPT. 2002 173 AUSTRALIAN BIRD WATCHER 2002, 19, 173- 177 Notes on the Black Bittern Jxobrychus flavicollis in Far Eastern Victoria AB. POLLOCK1 and P. NODEN2 1Queensland Herbarium, Mount Coot-tha Botanic Gardens, 1bowong, Queensland 4066 2Double Creek, Mallacoota, Victoria 3892 Summary Recent sightings and observations of the Black Bittern Ixobrychus fiavicollis from far East Gippsland are presented, adding significant new information for this species in Victoria. This comes from a collation of Atlas of Victorian Wildlife records and observations from local naturalists. In this region, observed habitat appears to be near-coastal locations closely adjacent to major streams and inlets, frequently in dense Melaleuca thickets. Breeding has also been observed in these habitats. Within the small area of its known range in far eastern Victoria, this species appears to be widely distributed, although rarely observed, and records are apparently highly seasonal. Introduction The Black Bittern Ixobrychus flavicollis is a secretive waterbird and is infrequently recorded in far eastern Victoria (Beste 1971, Blakers et al. 1984). Its distribution in this region remains unclear. The aim of this paper is to outline further information derived from unpublished observations made between 1935 and 1998 from both Atlas of Victorian Wildlife (2001) records and those of local naturalists, adding to the sparse accounts published for this species (Marchant & Higgins 1990). Sightings and local distribution Beste (1977) first observed this species in Victoria at Mallacoota Inlet in October- November 1971, and Drummond (1983) published details of the second known observation of a Black Bittern from along the Wingan River about 5 km from the river mouth, on 7 February 1983. A single Black Bittern was sighted in October 1991 in a roadside drain close to the Mallacoota Road in the vicinity of Mangans Lake, 3 km east of the Genoa township (D. Hollands pers. comm.). Pat Noden, a long-time resident of Double Creek (37°3l'S, 149°4l'E) near Mallacoota, has recorded intermittent sightings of Black Bitterns close to the family property. Photographic records indicate that the species has been present and breeding in the vicinity since 1939 (PN pers. obs.). The Atlas of Victorian Wildlife (2001) holds records in this locality from 1935 to 1991. The most recent observation in this area was made on the bridge over Double Creek in March 1991 by A. Robinson (A. Robinson, pers. comm. to PN). Other observations at Mallacoota Inlet include several from near Gypsy Point, a well­ frequented haunt of bird observers (e.g. Pizzey & Knight 1997), and Harrisons Creek (Atlas of Victorian Wildlife 2001). A single Bittern was flushed by AP near the Rothe Track crossing of Reedy Creek, 5.5 km south-east of the Cann River township, on 3 November 1991, during an ecological survey of the Tamboon Forest Block undertaken by the then AUSIBALIAN 174 POLLOCK & NODEN BIRD WATCHER Department of Conservation & Natural Resources. The bird was readily identified by its shape, large sharp-pointed bill, and overall blue-black colouration with a distinctive white-yellow stripe along its neck. It perched briefly in a small dead eucalypt overhanging water before flying off. This record remains the most westerly observation (37°36'S, 149°10'E) in Victoria. An injured Black Bittern was observed close to the Mallacoota township by the then Department of Conservation & Natural Resources ranger Rod Newnam in 1993 (R. Newnam pers. comm.). This Bittern was unable to fly, and later died in captivity. Two adults with a single juvenile were recorded on Little Genoa Creek, on 9 January 1995 (Atlas of Victorian Wildlife 2001). In summary, the species has been recorded from close to the coastal Victorian/ New South Wales border to the lower catchment of the Cann River, a distance of some 70 km. Records are mainly from Mallacoota Inlet (Atlas of Victorian Wildlife 2001 ). Most Black Bittern records are of single individuals, with few observations of pairs or juveniles and nestlings (Atlas of Victorian Wildlife 2001 ). Habitat Dense thickets of Giant Honey-myrtle Melaleuca armillaris close to water appear to be important habitat for Bitterns recorded near Double Creek. The Bittern observed near Genoa was seen in a drain close to roadside shrubs (D. Hollands pers. comm.), whereas the Bittern on Reedy Creek was disturbed from riparian scrub dominated by Scented Paperbark M squarrosa and Tall Saw-sedge Gahnia clarkei. Common to all these habitats is the presence of a closed thicket of tall shrubs or small trees close to a large permanent waterbody. All records with detailed locality information occur within 200 m of permanent water and at elevations of less than 50 m above sea level (Atlas of Victorian Wildlife 2001). They also show that both tidal and non-tidal habitats are inhabited by this species in far East Gippsland. Nesting habits Black Bitterns have been observed nesting at Double Creek in a forked Giant Honey-myrtle overhanging water. The nest was a large untidy basket of fine twigs. Nestlings were first recorded on film here in January 1939 (PN pers. obs.). A nest in a slightly different location was observed during World War II (PN pers. obs.). More recently, four eggs were recorded in a nest on 9 January 1989; by 29 January five chicks were photographed at this nest (Plate 43). On 30January1991, four downy chicks were seen and photographed in a new nest in the same tree (Plate 44). These photographs also show the nestlings bitterning (directly facing an intruder and raising head and neck vertically) while being observed (Plate 42, front cover), a behavioural response thought to help evade detection by predators (Marchant & Higgins 1990). The records presented here suggest that Bitterns (or their progeny) show site fidelity for breeding, as reported for this species in northern Australia (Marchant & Higgins 1990). These observations, together with records of juveniles (Atlas of Victorian Wildlife 2001 ), suggest that a small but regular summer breeding population is present in far eastern Victoria. VOL. 19 (6-7) mNE-SEPT. 2002 Black Bittern in Far Eastern Victoria 175 Nest with four downy Black Bittern chicks in Giant Honey-myrtle, Double Creek area, about 8 km north-west ofMallacoota, far East Gippsland, Victoria, 29January1989. Note bitterning behaviour. Plate 43 Photo: Pat Noden Juvenile Black Bittens in dense Giant Honey-myrtle nest-tree, Double Creek, Victoria, 1991. Plate 44 Photo: Pat Noden AUS1llALIAN 176 POLLOCK & NODEN BIRD WATCHER Food Despite intensive observation, the Black Bitterns at Double Creek were never seen bringing food to their young by day. The only record of feeding in this location was of a single individual preying on freshwater shrimp (probably Paratya ), during a drought season (PN pers. obs.). Seasonality Sightings of Black Bitterns in Victoria have been restricted to the warmer months, from October to April. Individuals appear to be most frequently observed between November and April, but especially in summer, with 69% of observations between January and February (Atlas of Victorian Wildlife 2001 ). It is not known whether this reflects a seasonal migration pattern of the species or if detectability declines in winter, as this species is highly cryptic and is not easily observed even when close to settlement (PN pers. obs). More records may be obtained by observers entering local riparian scrubs and Melaleuca thickets to search for this species. Status The few records of the Black Bittern in eastern Victoria make population estimates difficult. Its apparent preferred habitat of dense shrub thickets close to water is widespread along coastal rivers and streams in East Gippsland. However, this environment is difficult to access and is seldom visited. It appears likely that most, if not all, recent sightings are of different individuals, suggesting that the species is widely distributed across suitable wetlands in far East Gippsland. Although probably locally common in these areas, its secretive habits, drab colouration and its location in dense habitat mean that it is rarely observed and infrequently recorded. Census methods Suitable habitat for the Black Bittern in far eastern Victoria is readily identified. The presence of the species could be confirmed by systematic survey on foot or by boating closely beside inundated riparian thickets to flush individuals, or by searching for its large nest (which is distinctive, at least in this area, in always being built in a fork over water). PN reports the species calling in January after nesting, and censuses would therefore seem to be most productive just before and after nesting, in the months of December and January. Whether this species responds to call playback is unknown. Vocal imitation of the Little Bittern I. minutus advertising call can sometimes be effective in inducing calls (R. Jaensch pers. comm.), and similar methods may also be useful for the Black Bittern. Acknowledgements Dr David Hollands provided information of his sightings of Black Bitterns and discussed their significance. Thanks go also to Rod Newnam for his record from Mallacoota. Dr Stephen Henry, Andrew Mcl ntyre and Roger Jaensch gave helpful comments in the preparation of this paper. A ndrew Corrick and Barbara Baxter (Arthur Rylah Institute, De partment of Conservatio n, Natural Resources & Environment) kindly provided relevant Atlas of Victorian Wildlife records. VOL. 19 (6-7) JUNE-SEPT 2002 Black Bittern in Far Eastern Victoria 177 References Atlas of Victorian Wildlife (2001), Unpublished records of the Black Bittern, maintained by the Department of Natural Resources & Environment, Victoria. Beste, H. (1977), 'Black Bittern - a Victorian Record', Bird Observer 548, 57. Blakers, M., Davies, S.J.J.F. & Reilly, P.N. (1984), The Atlas of Australian Birds, Melbourne University Press, Melbourne. Drummond, R. (1983), 'The second Victorian record of a Black Bittern', Australian Bird Watcher 10, 136. Marchant, S. & Higgins, P.J.