Corella,2004, 28(3): 79-81 DIETOF THE EASTERNBRISTLEBIRD Dasyornis brachypterus lN NEW SOUTHWALES LINDA GIBSON' and JACK BAKERz 'Ausiralian Museum.6 College Street, Sydney, New South Wales 2010 ,tnstirute of Consfrvalion Biology, Departmcnt of Biological Sciences,University of Wollongong, New South Wales 2522 Re(ei'red. l7 O(tober 2043 The diet ol the Eastern Bristlebird Dasyorris bGchypterus in New South Wales was determined from observations and an analysis of faeces, stomach and gut contents ol 18 birds caught in or obtained kom Booderee National Park, Jervis Bay and Barren Grounds Nature Reserve, New South Wales.The study showed th€se birds largelytake mobil€terestrial invertebratespecies, the majorilyof which are ants and beetles. There is some indicationthat plant material, especially seeds, are also part of the diet. Observationssuggest that the diet is opportunisticand based on loraging behaviourof'peck it and see'. INTRODUCTION STT'DYAREA AND METHODS The rare Eastem Bristlebird Dasyornis brachypterus The specimens used in this study were obtained from two sites. (Passeriformes:Pardalotidae), is a small, semi-flightless, Booderee National Park, (35"08'5, 150'458) a Commoowealth of Australia owned area lhat occupies most of the Bherwerre brownishbird inhabitinglow, densevegetation in coastal Peninsula,on the southem side of Jervis Bay, on the south coasl and nearcoastal south-eastem Australia. It once occurred of N€w South wales and Barren Grounds Nature Reserve(34'40'5, in an almost continuous distribution from southern 150"42'E) on ihe Illawarra plateau, wcs( of Kiama, New South Queenslandto western Victoria (Baker 1997). Habitat Wales. Landform oD the coastal site consists of undulating sandsto[e change, however, through clearing and fire has caused a wilh large areas, particularly on the western side, covered with (Taws These wide variely (Garnett saod dunes 1997). areas support a of significantshrinkage of its range 1993),It is now vegetation types including eucalyp! forest and woodlands, coastal conflnedto isolatedpockets of its range and is listed as scrub. wet and dry heaths, rainforests and wetla0ds. Banen Grounds an endangeredspecies under the New South Wales Nature Reserve, located on a plateau, supports vegetation types Threatened Species Conservation Act 1995 and the lypical of a highland moist climale. These largely consist of Commonwealth EPBC Act.1999. Garnett and Crowley heathland,woodland, wet sclerophyll forcst and rainforest- (2000) support these listings by describing the species The material for this study consisted of faeces (l specimen), conservationstatus. Ther€ is little documentedinformation gut flush (5 specimens),gut flush and faeces (7 specimens)and lhe whoie guts of a bird that that died while being handled and available on the diet of the EasternBristlebird and we five birds that were killed on the roads of Booderee National Park. wondered whether dietary specializationcontributed to the The malerirl was collecled in Spring (13 samples),Summer (one), rarity of the species.Previously there have been several Aulumn (four) and Winter (one) during the period 199l-1995. brief mentionsof the EasternBristlebird's diet and Higgins Faecesfiom live birds were obtained by holding them in a clean and Peter (2002) summarizedthese data. Gould (1865) 'insects cloth bag for less lhan 20 minutes and collecting the material that proposedthat the speciesate of various orders' lhey defecated.Gut flushing involves introducing 6 milliletres of although his account did not indicate the basis of this distillcd waler through a 3 millimetre silicon rube inro the gizzard description.North (1904) reported that an unspecified of the bird via the mouth (after Major 1990). This caused ihe 'contained regurgilation of the water and some contents of the slomach. number of EasternBristlebird stomachs only the remainsof insects'.Lea and Gray (1935)misidentified Each sample of faeces, gut flush and whole gut contents was divided as Rufous Bristlebird Dasyornis broadbenti, two Eastern into smaller sub-samplesrepr€s€nring what appearedro be the najor significant contenl components,e.g. gut flush containirg bristlebird liom (Chaffer Mallacoota, Vicroria 1954: invcrtebrateremains, gut flush containing plant remains.This gross Wakefield 1958). The guts of these birds were reported ro sort was important where thc faeces and gut flush sampie were contain fragments of cicada, cockoach and beetle; seeds oblaincd from the same bird. Samples were stored in 70 per cent of Epacridaceae,Exocarpus (Native cherry) and Lyciurn ethanol, Thcse sub-samples were examined using a binocular dissecting microscope and identification (African boxthorn); and fine grit (Lea was made possible using ferocissinun and the reference collection and experrise of the Entomology Gray 1935).Wakefield (1958) section notedrhar Aliican box-rhorn of the Australian Muscum. The resulls (Table l) show the number was not known to occur in the Mallacootadistrict, which of times an identified i(em occurred in a sample type. Opportunistic casts doubt on the accuracy of the Lea and Gray report. observations of Eastcrn Bristlebird feeding were also recorded during period Barker and Vestjens (1990) reported a single Eastern the 1992-2002. Bristlebird specimen that had eaten ctcadas,Melampsalta RESU]TS sp. rnd Chapman(1999) observed a bird feedingon the nectirr of Banlsio ericifolia.The currenrwork inv;sfiqates Most of the samples consisted of the remains of faecal gul and contentsoI ErsternBristlebircls and reporr, invertebrateswith a small componentconsisting of plant on a numberof feedingobservations. remains,especially seeds of plants(Table l). Approximately 79 80 L. Gibson and J. Baker: Diel ol th6 Eastern Bris ebjrd Dasyornis brachyptetusIn New South Wales Core a 2B(3) TABLE I Results.Numbers number of times ilem occurred. Sample Type Fa€ces cut FlushWhole gut Irem lD Family Sub-family Genus/Species N=8 N=5 N=6 Invertebrate material Coleoplera Curculionidae 5 Cucujoidea 5 5 2 2 Scarabaeidae 2 'IYpe I 'IYp" 5 2 4 2 1 I 3 Type 3 2 Unidentifiable Coleoptera 2 Hymenoptera 2 3 2 Formicidae Dolichod€rinae I Myrmiciinae Crematogastissp. I Monomoriumsp. 1 Pheidolc sp. 3 Tetramorium sp. I Formicinae Notoncussp. Petalrechina sp. I Polyrhachis sp. Prolasiussp. 2 Stigmacrossp. 2 Ponierinae I Rhytidoponera victoriae Rhytidoponera tasmaniensis I Rhytidoponerametallica 2 3 Rhytidoponera sp- 2 Unidentifiable Formicidae 3 I I Mantodea I Diptera I I UIidentified larvae I I I Arachnida 2 I Plant and Fungal Marerial Plants Stellaria I Juncussp. I Unidentifiable Plants 5 4 Seeds Mimosaceae Acacia sp. I Cyperaceae Carex sp. I Poaceae 2 Unidentifiable Seeds Type I 4 TYpe2 TYp. 3 'Ilpe 4 Type 5 Unid€ntifiable 50 per cent of the samplesalso containedfine quartz numbersof individual ants consumedwas also hish. One grains.which is consistentwith ground-feedinganimals animalhad evidence of47 ants,anorher 67 individJalanrs. foraging on a sandy terrain. Thirty feeding observations were recorded, The insect remains were mainly from two groups: 20 of birds pecking the ground, three pecking at branches Formicidae, the ants, and Coleoptera,the beetlis. All and foliage in scrubs and seven birds carrying invertebrates invertebrate remains identified were from four orders of in lheir bills. Pecking on the ground was thought to be for insect or from the Arachnida (spiders, mites). Where ants on five occasionsand confirmed to be for ants on a further possible,ants were further identified at least to -significantAenuslevel. five, twice when birds were pecking ants as this group obviously representeda from around the ants' nest. On one occasion a bird was observed proportion of the items taken by the birds. Ten ant genera in a heath banksia Banksia ericfolia from four subfamilies were identified in the samples. that was in flower, dripping nectar down the branches.The nectar was attracting ants. Of the five ant subfamilies found in southern Australia on which the bird was feeding. One bird ar Jervis Bay (Andersenl99l), only the Myrmeciinae,the bull antsand pecked at rolled oats and bread crumbs on the sround and jumper ants, wore not detectedin the diet samples,although a bird at Banen Ground peckedat a breadcruit but then they are common at Jervis bay and Barren Grounds (Gibson disregardedit. On one occasion at Barren Ground, a bird 1999). It was not only the variety of forms taken but the was observed taking tadpoles of the Common Froglet Seotember.2OO4 L. Gibsonand J. Baket:Diet ol the EasternBristlebird Dasyornis brachypletus in New SouthWales 8l Crinia signfera, from drying puddles.Birds carried an taking other inverteb.ates,tadpoles, seeds, other vegetation unidentifiedlarva (n = l), small (10-25 mm) unidentified and even bread crumbs and they are able to break up invertebrates(n = 4) and stick insects(n = 2;40-60 mm) invertebrate prey, such as stick insects, which is too large Phasmatidae,one of which was bashedagainst a branch. to swallow whole. They seemto avoid Myrmeciinaeand take few Arachnida, even though bull ants and spiders are DISCUSSION common in their habitat. The study fbund that the Eastern Bristlebird took a ACKNOWLEDGMENTS limited range of invertebrates,consisting largely of ants All Bristlcbirdswere captured under NSw NationalParks and and beetles.These are very common groups of insects, wildlife permitnumber A1320. Procedures involving gut flushing both where the bird occurs and in nearbysimilar reserve werecarried out underthe Universityof Wollongong'sanimal care lands (Gibson