NORTHERN SHRIKE-TIT CRESTED SHRIKE-TIT Falcunculus (Frontatus) Whitei
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Threatened Species of the Northern Territory NORTHERN SHRIKE-TIT CRESTED SHRIKE-TIT Falcunculus (frontatus) whitei Conservation status Australia: Vulnerable Northern Territory: Near Threatened Photo: T. Collins Description The northern shrike-tit is a distinctive medium-sized bird. It has a dull green back and wings, yellow belly and boldly marked black and white head, with a small black crest. Its bill is unusually deep, strong and hooked. Distribution This taxon forms part of a superspecies of three geographically isolated populations, in eastern and south-eastern Australia, south-western Australia and northern Australia. These taxa are variously accorded subspecific (Christidis and Boles 1994, 2008) or full specific (Schodde and Known locations of the northern shrike-tit Mason 1999) status. Molecular genetics analyses are required to resolve the taxonomy within the to near Borroloola. More recent records in the superspecies. Northern Territory (NT) expand our knowledge of them here and include locations in north east Until relatively recently there were remarkably Arnhem Land to Kalkarindgi (semi-arid Victoria few records of the northern shrike-tit (Robinson River District). The most frequent recent records and Woinarski 1992), scattered between the are from the Sturt Plateau and from the south-west Kimberley (Western Australia) east Maningrida area (R. Noske pers. comm.), though For more information visit www.denr.nt.gov.au 2 this reflects greater research effort in these Northern shrike-tits use calls to maintain pairs areas. and territories, particularly during the breeding season. These calls, though not loud, are The species has not been relocated in the distinctive and provide the best means of Borroloola area since it was first recorded there detecting the subspecies at a location (Ward in 1913. However, there have been no recent 2009). surveys targeting the species in this region (Ward 2009). Conservation assessment Assessment of conservation status is hampered Conservation reserves where reported: by the relative paucity of records, and lack of Elsey National Park, Kakadu National Park and information on limiting factors or threatening Nitmiluk National Park. processes. Robinson and Woinarski (1992) suggested a possible decline (based largely on Ecology absence of recent records from the original The subspecies occurs across a range of eucalypt collecting site near Borroloola) and a possible and melaleuca woodlands (Robinson and impact from frequent fire, but the available Woinarski 1992; Ward pers. obs.); from evidence is limited. relatively wet, though still strongly seasonal, areas in Arnhem Land to semi arid woodlands of The conservation status of the species the southern Victoria River District. However, approaches threatened categories (under the subspecies is very patchy throughout this criterion C) based on: range and occurs at low densities within any • a total population size <2 500 mature patch. Studies on Jawoyn lands, south of individuals Katherine, recorded them living in territorial pairs, each occupying about 25 ha and at But there is no evidence of continuing decline densities of approximately 1.25 adults/km-2 and the subspecies is probably more widespread within preferred habitat (Ward 2008). than currently recognised. The subspecies is classified in the NT as Near Threatened. Northern shrike-tits are insectivorous and cicadas, katydids, tree crickets, spiders and Threatening processes (beetle) larvae have been observed being eaten. This subspecies is thinly and patchily spread over They forage in tree canopies, generally quietly a large distribution but it is unclear what factors and slowly seeking invertebrates on foliage, influence habitat selection within areas. It is under bark or in dead wood. The massive bill is likely that different threats occur in different extremely strong, and is used for chiselling and parts of its distribution. Habitat quality may be tearing bark, branches and foliage to access affected by fire or grazing regimes, as these may invertebrates (especially larvae) sheltering within. determine the density of large trees and the abundance of the principal food items. Breeding occurs over the Wet season. Pairs start However, there is a need to determine the building nests in September-October and egg optimum fire regime. On the Sturt Plateau laying can occur between October and March. populations persist in reasonable numbers in Fledged chicks may still be dependent on their areas that are burnt every year and in areas that parents in March-April. Fecundity is low with are heavily grazed. two to three eggs laid per clutch but never more than one chick observed per pair. Nest failure The low density of local populations and their rate is high and re-nesting erratic. patchy distribution across the landscape render 3 this subspecies especially susceptible to habitat Australasian Ornithologists Union Monograph 2. (RAOU, Melbourne.) fragmentation in areas of extensive land clearing. Christidis, L., and Boles, W.E. (2008). Systematics and Taxonomy of Australian Birds. (CSIRO Publishing, Conservation objectives and management Melbourne.) There is a national recovery plan for this species Garnett, S.T., and Crowley, G.M. (2000). The Action Plan for (Woinarski 2004). In that plan, Research Australian Birds 2000. (Environment Australia, Canberra.) priorities are to: Robinson, D., and Woinarski, J.C.Z. (1992). A review of i. provide a more precise estimate of total records of the Northern Shrike-tit Falcunculus population size and trends; frontatus whitei in northwestern Australia. South Australian Ornithologist 31, 111-117. ii. investigate the ecology of the species, with Schodde, R., and Mason, I.J. (1999). The Directory of particular attention to characteristics Australian Birds: Passerines. (CSIRO, Melbourne.) associated with habitat suitability; and Ward, S.J. (2008). Habitat-use, foraging and breeding iii. assess the impacts of a range of fire regimes. ecology of the northern shrike-tit Falcunculus frontatus whitei. Report to NHT (Department of Natural Compiled by Resources, Environment, The Arts & Sport, Darwin). John Woinarski Ward, S. (2009). Survey protocol for the northern shrike-tit Falcunculus frontatus whitei Simon Ward http://www.nt.gov.au/nreta/wildlife/animals/threaten [updated December 2012] ed/pdf/NST_survey_protocol_Aug09.pdf Woinarski, J.C.Z. (2004). National multi-species Recovery References Plan for the Partridge Pigeon [eastern subspecies] Geophaps smithii smithii; crested shrike-tit [northern Barrett, G., Silcocks, A., Barry, S. Cunningham, R., and (sub)-species] Falcunculus (frontatus) whitei; masked owl Poulter, R. (2003). The New Atlas of Australian Birds. [north Australian mainland subspecies] Tyto (Birds Australia, Melbourne.) novaehollandae kimberli; and masked owl [Tiwi Islands Christidis, L., and Boles, W.E. (1994). The Taxonomy and subspecies] Tyto novaehollandiae melvillensis, 2004- Species of Birds of Australia and its Territories. Royal 2008. (NT Department of Infrastructure Planning and Environment, Darwin.) .