J. Field Ornithol., 62(3):386-389

COMPARATIVE BATHING BEHAVIOR IN SOME AUSTRALIAN

N. A.M. VE•EEK Departmentof BiologicalSciences SimonFraser University Burnaby,British ColumbiaV5A IS6, Canada Abstract.--The bathingbehavior of Alcedinidae(2 ),Dicruridae (1), Meliphagidae (16), Meropidae (1), Muscicapidae (5) and Zosteropidae(1) is describedand compared with that of other species.The birds were observedfrom a blind while they bathed in a water hole with a sloping shore line and flanked on one side by shrubs.Two forms of bathing were noted: diving from shrubsand wading into shallow water. Although more data are needed,it is suggestedthat the bathing methodsused by birds differ at the generic level and not necessarilyat the family level. ESTUDIO COMPARATIVO DE LA CONDUCTA DE BAI•ARSE POR ALGUNAS AVES AUSTRALIANAS Sinopsis.--Sedescribe y comparala conductade bafiarsede Alcedinidae(2 especies),Di- cruridae(1), Meliphagidae (16), Meropidae (1), Muscicapidae(5) y Zosteropidae(1) con la de otras especies.Las avesse observarondesde escondijos mientras se bafiabanen un ojo de agua flanquedoen un lado pot arbustos.Se noratondos formas de bafiarse:tiffindose en clavado desdeun arbusto y andando o brincando desdela orilla hacia agua de poca pro- fundidad.Aunque se necesitanmils datos,sugiero que el m•todo de bafiarseutilizado pot las avesdifiere a nivel de g•nero y no necesariamentea nivel de familia. Although someforms of feather maintenancebehavior have been stud- ied in detail (e.g.,preening, Hatch et al. 1986, Ierseland Bol 1958) others (e.g., bathing) are rarely mentionedin the literature (Burtt 1983). As most feather maintenanceactivities occur infrequently and unpre- dictablyand are often of short duration, they are difficult to study sys- tematically.Simmons (1964) and Slessers(1970) reportedon the different bathing techniquesof birds and made the first attemptsto compareand interpret them in terms of morphologyand ecology.The observations here reported show that theseinterpretations may have to be modified.

METHODS AND RESULTS On 9-17 Dec. 1988 I observedbirds from a blind pitchedat a human- made water hole on the Quaalup Homestead,an enclavein Fitzgerald River National Park, W.A., Australia. The water hole had a gently sloping,sandy shore; a water surfaceat the time of the studyof 14 x 17 m and was locatedin a woodlanddominated by Eucalyptusoccidentalis with an understoryof Acaciacyclopis. Along one side shrubsand small treesgrew near the water'sedge and a few branchesof larger treeshung over the water hole. Bird nomenclaturefollows Slater et al. (1988). The birds showedtwo kindsof bathingbehavior. Some species walked or hoppedinto the shallowwater alongthe shore,others variously dove into or onto the water, 3-5 timesper bath. Amongthe ,Red Wattlebirds (Anthochaeracarunculata) (n = 96) dove from an estimated

386 Vol.62, No. 3 Bathingin Birds [387

height of (mean + SD) 1.8 + 0.7 m (n = 12) from perchesin shrubs alongthe shoreor from treebranches hanging over the pond.They entered head first, 1.5 + 1.0 m (n = 12) from the shore, and at times were momentarilysubmerged. The birds perchedfollowing each dive, shook their feathers,hastily preened and bill-clapped. White-naped Honeyeaters (Melithreptuslunatus) (n = 25) dovefrom a height of 1.8 + 0.8 m (n = 12), enteringthe water 2.5 + 1.1 m (n = 11) from shore,often submerging completelyand floating briefly beforereturning to a perch. The degree of submergence,as was the casein Red Wattlebirds,appeared dependent on the number of divesbecause on the first dive the birds just hit the water with a splash,being apparentlytoo buoyantto go under. The five timesI sawWestern Spinebills (Acanthorhynchus superciliosus) dive, their behaviorwas very similar to that of Red Wattlebirds and White-naped Honeyeaters.There appearedto be a dichotomyamong the honeyeaters. The three speciesof honeyeatersmentioned above dove from heightsof 1.5 m or more while Brown (Lichmeraindistincta) (n = 29) and Singing Honeyeaters(Lichenostomus virescens) (n = 2) perchedlower (<80 cm) and droppedinto the water closer(< 50 cm) to the shore.The latter two speciesappeared more cautiouswhen bathing than the others, staying closebelow or near the only shrubthat hung partly over the edgeof the waterhole.For both speciesthe distancebetween the perchand the water surfacewas too short to allow them to submergeupon impact. Brown Honeyeatersdropped almost vertically to the surfaceof the water, briefly floated and splashedand hurried back to the shrubs.Besides the hon- eyeatersmentioned, Restless Flycatchers (Myiagra inquieta)(n -- 2) dove boldly, resemblingWhite-naped Honeyeaters.Sacred Kingfishers (Hal- cyonsancta) (n = 6) dove from low perches(<50 cm) while Rainbow Bee-eaters(Merops ornatus) (n = 7) dovefrom a flight overthe waterhole. Unlike other honeyeaters,Tawny-crowned Honeyeaters (Phylidonyris melanops)(n = 3) approachedon foot and bathed standingin shallow water. The congenericNew Holland (P. novaehollandiae)(n = 76) hoppedtowards the water's edgefrom branch to branch and then jumped onto the shoreor into the shallowwater from a height of 0.3 + 0.1 m (n = 23). When New Holland Honeyeatersbathed together (up to 12 birds), which they tended to do, most of them dispensedwith descendingthrough the branchesand insteadmoved directly to the water's edgeover the ground.Silvereyes (Zosterops lateralis) (n = 75) approached the water the way New Holland Honeyeatersdid. They appearednervous, jumped in and out of the water and barely got wet. Unlike Restless Flycatchers,Willy Wagtails (Rhipidura leucophrys)(n = 9) and Grey (R. fuliginosa)(n = 5) bathedby standingin shallowwater near or away from the shrubsas if cover were unimportant to them. They bathed in one continuoussession rather than interrupt it by goingback to shoreseveral times as did all the other species. The gentlysloping shore as well as the nearbyshrubs offered the full rangeof possibilitiesto enter the water, soit seemsreasonable to assume that eachspecies performed as it did by choice.In situationswhere nearby 388] N.A.M. Verbeek J.Field Ornithol. Summer 1991 shrubs,overhanging branches and/or water that is shallow enoughto standin are absentthe speciesperhaps may bathe differently. Whether they have the behavioralflexibility to do so I do not know, but I doubtit. Besidesthe speciesmentioned. I have seenbathing in other Australian birds elsewhere.All the additional speciesdove from perches:Yellow- facedHoneyeater (Lichenostomus chrysops) (see also Waterhouse 1946), White-plumed Honeyeater (L. penicillatus)(Immelmann 1961, Perry 1946), White-gapedHoneyeater (Meliphaga unicolor) (Immelmann 1961), Black-chinnedHoneyeater ( gularis), White-throated Honey- eater (M. albogularis), ( melanocephala),Blue- facedHoneyeater (Entomyzon cyanotis), Silver-crowned (Phi- lemonargenticeps), (P. citreogularis),Spangled Drongo (Dicrurusmegarhynchus), Satin Flycatcher(Myiagra cyanoleuca),Leaden Flycatcher(M. rubecula)and ForestKingfisher (Halcyon macleayii). Im- melmann (1961) reporteddiving in five additionalspecies of honeyeaters and Waterhouse(1946) mentionsthe EasternSpinebill (Acanthorhynchus tenuirostris).Immelmann's (1961) statementthat apparentlyonly small honeyeatersdive is incorrect,as I saw diving in suchlarge speciesas , Silver-crownedFriarbird and Blue-facedHoneyeater.

DISCUSSION Why somebirds bathe while standingin shallowwater, whereasothers dive, is unclear. Slessers(1970) concludedthat "anatomical structure and habits" mainly dictatedthe methodof bathing. For instance,aerial birds suchas swallowsand swiftsbathe on the wing becausetheir legsare too shortand weak and their wings too long to bathe while standingin water (Slessers1970). It is difficult to see, however, how anatomy contributes to bathing by diving as found in tyrannid flycatchers(Eastern Phoebe (Sayornisphoebe),Eastern Wood Pewee(Contopus virens) (Slessers 1970), Flycatcher (Empidonax traillii) (Burtt 1983) and Fork-tailed Flycatcher(Muscivora tyrannus) (Lamar 1983) and muscicapidflycatch- ers (Leaden, Restlessand Satin Flycatcher,this study).These birds ha- bitually dive on their insectprey in the air and their diving into water to bathe might be a likely extensionof their feedingbehavior. The same argumentmay apply to bee-eaters,among which severalspecies are re- ported to dive into water (Fry 1982, Reynolds 1975, this study), and drongos.Inconsistent with this argument is that two other muscicapid flycatchers(Willy Wagtail and Grey ) batheby standingin water. Their erratic pursuit flightsafter ,involving aerial twistsand turns, do not extend logically into diving into water. Are they too light? Then there are the many honeyeaters(Immelmann 1961, Perry 1946, Water- house 1946, this study), Red-eyed Vireo (Vireo olivaceus)and Indigo Bunting (Passerinacyanea) (Slessers 1970), that dive to bathe and are not obviouslyhampered by anatomy or feeding behavior to do otherwise. Although long-billed honeyeaterstake insectsby (Ford and Patton 1976), in which habit they couldbe, for purposesof this paper, Vol.62, No. 3 Bathingin Birds [389

looselyequated with flycatchers,short-billed honeyeaters primarily glean insects,yet they dive into water just as well as the long-billedspecies. Although more data are needed,it is tempting to suggestthat taxo- nomically,the various bathing methods shown by birdsdiffer at the generic level,not necessarilyat the family level.Among honeyeaters, the genera Acanthorhynchus,Anthochaera, Entomyzon, Lichenostomus,Lichmera, Manorina,Meliphaga, Melithreptus and Philemon dive, while Phylidonyris standsto bathe. The fact that the genusPhylidonyris is an apparent exceptionneeds further study.Similarly, amongthe muscicapidflycatch- ers, Myiagra divesand Rhipidura standsto bathe.

ACKNOWLEDGMENTS

I thank Norma and GeoffreyKeen for their help, hospitalityand the freedomthey gave my wife, Rosalinda,and me to roam overtheir property,Ron Woollet and Ken Richardson for the useof their researchtrailer and the use of the blind, and Murdoch Universityfor its hospitality.Ron Woollet madeour all too shortstay in WesternAustralia a pleasureby anticipatingour needs.I thank Jed Burtt, Ken Yasukawaand an anonymousreviewer for their helpful comments.

LITERATURE CITED

BURTT,E. H., JR. 1983. Comparativeimplications of bathingby a Willow Flycatcher. J. Field Ornithol. 54:417-418. FORD,H. A., ANDD.C. PATTON. 1976. Resourcepartitioning in the honeyeaters(Meli- phagidae)in southAustralia. Austral. J. Ecol. 1:281-287. FRy, C. H. 1982. Water-diving behaviourof Carmine Bee-eaters.Ostrich 53:244-245. HATCH,K. K., L. LEFEBRE,AND R. E. LEMON. 1986. Preeningin the Veery and the American Robin: evidencefor a singletiming hierarchy.Behav. Processes12:227-236. IMMELMANN,K. 1961. Beltrage zur Biologieund Ethologieaustralischer Honigfresser (Meliphagidae).J. Ornithol. 102:164-207. IERSEI,J. J. A., vaN, ^ND A. C. A. BOL. 1958. Preeningof two tern species.A studyon displacementactivities. Behaviour 13:1-88. L^M^R,W.W. 1983. Unusualbathing behavior of theFork-tailed Flycatcher in Colombia. Wilson Bull. 95:488-489. PERRY,W. 1946. Submergedbathing by honeyeater.Vict. Nat. 63:184. REYNOLDS,J. F. 1975. Birds bathingby divinginto water. Bull. E. African Nat. Hist. Soc. 1975:114. SIMMONS,K. E. L. 1964. Feather maintenance.Pp. 278-286, in A. L. Thomson,ed. A new dictionaryof birds. McGraw-Hill, New York, New York. SLATER,P., P. SLATER,AND R. SLATER. 1988. The Slater field guideto Australianbirds. Landsdowne-Rigby,Willowby, Australia. SLESSERS,M. 1970. Bathing behaviorof land birds. Auk 87:91-99. WATERHOUSE,D. 1946. Submergedbathing by honeyeater.Vict. Nat. 63:262. Received6 Dec. 1990; accepted12 Jan. 1991.