Corella,2008, 32(2\: 30-34

A POSSIBLETERRITORIAL AND NESTINGASSOCIATION BETWEENPIED AND GREYBUTCHERBIRDS nigrogularis and C. torquatus AND THE YELLOW-THROAIEDMINER flavigula

GRAHAM R. FULTON

Centle for EcosystemManagement, Edith Cowan Unive$ity, Joondalup,WA. 6027, . Email: $ahamf200 [email protected]

Recefued:30 January 2006

This study demonstratedthat Yellow-throatedMineis Manorina flavigulaarc aggressivebirds that exclude other species of from their territories. However,they did not exclude Grey ButcherbirdsCracticus torquatus or Pied ButcherbirdsC. ,,grogula/s from two widely separatedsites in WesternAustralia. Concurrently active nests of Yellow- throated Miners and Pied Butcherbirdswere lound within 10-30 metres of one another at Westonia.Yellow-throated Miners, and Pied and Grey perched close to each other without aggression.A territorial and nesting associationbetwoen these species is unexpected since both genera are aggressivetowards other species. Pied and Grey Butcherbirds may benetit from abundant arthropod resourcesthat are not exploited by miners, and in return, miners may benefitlrom the aggressiveabiliiy ofthe butcherbirdsto repulselarger nest-predators when miners cannot. The grouping of nests may aid all species in defendingtheir territoriesand may enhancetheir nesting success.

INTRODUCTION METIIODS

Speciesin the genus Manorina have been identified as Field sites birds that exclude other species from their terdtodes, sometimesleading to sole occupancyof a site (Dow 1977; Two field sites, Ejah and Westonia,were chosen with Loytn et al. 1983; Higgins et al. 20Ol). Inter-specific butcherbirdsand Yellow-throatedMiners presentat each.The teffitoriality has been report€d in Bell Miners Manorina sites were 563 kilometres apart to test if aIIy tedtorial melanophrys(Loyt et al. 1983; Clarke and Schedvin 1999), associations,between the two genem, applied over a broad Noisy Miners M. melanocephala(Dow 1977; Grey et al. geographicalarca. 1998), Yellow-throated Miners M. (Starks 1987) flavigula Ejahis an outcampat Mileura Station,about 800 kilometres and Black-eared Miners M. melanotis (Starks 1987; northeastof Perth;26" 24' S, I17"11'E.Mileuraisasheepand Mclaughlin 1990). cattlestation on the MurchisonPlains in the (semi-arid)mulga Despite the wealth of knowledge available on the Noisy zone of WestemAusftalia (seeDavies 1970, 1986).Ejah is a Miner and Bell Miner, and the rapidly expandingdata on the mesic areabecause of the runoff from an escaqrmentand is one Black-eared Miner, there has been surprisingly little of the few productive sites (with denservegetation) in the area. published on the agonistic behaviour of the Yellow-throated Observations were made over a four-hectare area: upon and Miner, despite its wide distribution across Australia. immediatelyadjacent to an escarpment(breakaway), up to and Yellow-throated Miners have been descdbed as aggressive at a dry ephemeralcreek. The creek was approximately150 to other birds (Mellor 1919), aggressive near the nest metres south of the breataway ald had denser vegetatiol than (Chandler 193'7), ot less aggressive than Noisy Miners the surroundingarea. The flora of the creek area comprised (Jeffery 1955). Eremophila spp.,Acacia spp. and Hakea spp. The dominant vegetationnear the breakawayconsisted of Acacia spp. and Butcherbirds Cracticus spp., catchlive prey including birds Eremophila spp.. as large as Common Blackbirds Turdus merula and Spotted Turtle-DovesStreplopelia chinensis (Pizzey and Knight 1997). Westonia(31' 18' S, 118'42'E) is locatedapproximately They are nest-predatorsidentified by photography (Major el al. 300 kilometreseast of Perth on the easternside of the central 1999),and havebeen observed taking nestlingsand adult birds wheatbelti[ WesternAusralia. It is situatedin 5 600 hectares (Hobbs 1981;Ta$urton 1991). of remnant bushland, known as Westonia Commons. Observations were recorded, over a foul-hectare arca, on the This study recorded inter-specific aggressionand nest edge of the small township in a suburbanarea and in adjacent positioning in two populations of Yellow-throated Miners, Salmon Gum salmonophloia, Gimlet E. salubris irl WesternAustralia, to establishif they are less aggressive and Red Morel E. longicomis woodland. Yellow-throated towards butcherbirds than other birds and to detect if Mine$ nested at both ends of this study area and Pied nesting together might provide any mutual benefit. Butcherbirdsnested at one end with Yellow-throatedMiners.

30 June2008 G.RFulfoni Possible territorial and nestino association between Pied and Grev Butcherbirds and the Yellow-throated L4iner

Field obseryations Aggre$ton

A combinedtotal of 27 hoursof observationswas madeat Yellow-thrcatedMiners were aggressiveto all birds (14 both field sites.Four hours of observationswere madeat Ejah species)except butcheftirds that entered the study areas(Table (fiom 29 June through 2 July 2004) one hour eachon four l). They also mobbed the Galah Cacatua roseicapilla, momings ranging from 0745 hourc and finishing at the latest Australian Rirgneck Bamardius zonarius, by 1030hours. Twenty hoursof observationswere undertaken Anthochaera carunculata, Spiny-cheeked at Westonia(21 a']'d,23 Apdl, and fuom 22 to 24 September Acanthagenysrufogalarls, Australian Rayen Corvus coronoides 2004). In September,ten houls werc undertakel iII both the ar'dLittle Crow C. bennetti. moming and evedng between0630 0900 hours oyer four days and 1500 - 1700 hours on five days. In April surveys A Grey chasedoff an Australian Ringneck (at were undertakenfor one hour on 21 April and two hours 23 Ejah), which had been harassedby Yellow-throated Miners but April: all were in the moming after sunrise.Old nestswere not displaced. At Westonia, a Red Wattlebird and a Westem identified becausethey were identical to the nests that were Corella Cacatua pastinator that had not been deterred by either being used or being built by Pied Butcherbirds-In Yellow-throatedMiners, within 15 metresof the inter-specific grcup addition, (StephenDavies pers. comm.) identified the old of nests, were subsequentlychased away by Pied Butcherbirds. nestsat Ejah as thesehe knew were built and used by Grey Butcherbirds.He also advisedme thatYellow-throated Miners DISCUSSION and Grey Butcherbirdshad occupied this same site for 45 continuous yeam. Yellow-throatedMineIS were considered An associatiol bet:vteen Manorind spp. and the Grey acting aggressivelyif they made deliberate contact with Butcherbirdis supportedby a considerableamount of anecdotal anotherspecies; swooped and causedanother species to leave data(Table 2), but thereis little evidenceof minersassociating the site, chasedanother species from the immediatearea; or if with Pied Butcherbirds(Table 2). Piper and Catterall (2003) one or more birds perched close to another species and reponed Pied and Grey Butcherbirds, along with other large harassedit by squawking,calling or by making short flights species,may be toleratedto some degrceby Noisy Mine$. toward it. Amold (2000a) did not see either Grey or Pied Butcherbirds mobbed by Noisy Miners, although other potential predatoG Yellow throated Miner's teritories were thoroughly were. In the present study, Yellow-throated Miners excluded searchedfor all nests.Nests were detectedby eitherfollowing other species ftom their own teritories and they did this birds that madercpeated flights to the samelocation, or while selectively,while exhibiting toleranceor acceptanceof Grey surveying.Distances between nests in the inter-specificgroup and PiedButcherbirds (Table 3). of nestsat Westoniawere measuredwith metle long stddes. The distanceof the two miner nestsgreater than 100 metles Many birds will toleratemost other birds perchingclose by, distantfrom the inter-specificgroup of nestswere estimated. except tbr n€st-predators and camivores (Pavey and Smyth A nest was consideredactive if it containedeggs, the female 1998;,\6o16 2000b;Fulton unpub.data). Close perchingard was laying or incubating. tolerantbehaviour described here are unexpected betweel such aggressivespecies as Yellow-throatedMiners, and Grey and An abundanceindex was calculatedby taking the meanof Pied Butcherbirds. Birds as predators of other birds typically hourly counts. To avoid double-countilg of any use stealth or surprise to attack (e.g. Wood 2000). When a bird individuals in the hour, the total hourly count was takenonly tums its back on a known predatory species it invites from the maximum numberof birds that could be seenat any opportunistic predation, or at the very least an aggressiveattack. one time. This figure is likely to underestimatethe true totals BreedingYellow-throated Miners tumed their backs on Pied of larger groupsof birds that are constantlymoving aboutthe Butche6irdsafter perching by their sidesand while foragingon study area. the ground together.It is doubtful that breedingYellow-throated Miners would be naiveabout the dangerof this action;it seems RESULTS reasonable to interpret this behaviour as 'trusting' and more Grouped nests than simply tolerant. The two most A group of four concurrently active nests, two Pied significantfactors affecting nest successare food and predation(Collias and Collias 1984; Martin i988a, Butcherbirdsand two Yellow-throatedMirlers, were detected 1988b,1992, 1995;Collias 1997).Butcherbirds take a vadety in WestoniaCommons. Two Yellow-throatedMiner nests(one of prey, which is dominated by larger invertebrates and with a bird laying and the other9070 built) werepositioned ten supplemented with small vertebrates such as small lizards mehes apart and were situatedwithin 30 metles of two Pied (Rose 1999). Butcherbirds,as predatorsand nest-predators, Butcherbirdnests (one with an adult on eggsand another70% may confer an advantageto mine$ by helping them maintain built). Two more Yellow-throated Miner nests, under terdtories and defend nest sites. In tum butcherbids may gain constructiou,were locatedapproximately 120 metres and 150 a nutritional benefit from miners controlling populations of metresfrom the inter-specificgroup of nests,but within the largeinsects by excludingother birds (Loyn 2002). four-hectarearea defended by Yellow-throatedMiners. No other active nestsof any specieswere detectedin this area. In this study, Pied and Grey Butcherbirds built nests ard Disused butcherbird nests were detected within the area foraged within territories defended by Yellow-throated Miners defended by Yellow-thoated Mine6 at Ejah (z = 3) and and the Pied Butcherbirdsnested close to the nestsofYellow- Westonia(, = 4). thrcated MineIS. In 2003. Grev Butcherbirdswere detected 32 G.R.Fulfon; Possible territorial and nesting association between Pied and Grey Butcherbirds and the Yellow-throated l\,4iner Corella32(2)

TABLE 1

Aggressionby Yellow-throatedMiners. Abundance = meanof hourly counts.Hourly count= maximumnumber of birds that werc prcsentconcurrently in an hour Aggressionmte index = incidents/ abundance.This index is not presentedwhere abundances were <1.0 becausethese rcsulted in unrealisticmeasures of aggression.The astedsk( * ) indicatesa commonnest-predator (see Brown and Brown 1986; Major et al. 1999; Bevy 2002: Fulton 2006a, b).

No. of Aggression Species Abundance incidents rateindex

G alah Cac atua ro se icapi I la 11 1.5 7.3 WesternCorella C. pqstinator I 0.1 RegentParot Polytelis anthopeplus 2 0.1 Australian Ringneck Barnardius zonarius I5 1.3 11.5 Red Wattlebird Anl?ochaera carunculate* 22 2.5 8.8 Spiny-cheekedHoney eater Acantho genys rufo gularis 7 1.0 7 SingingHoneyeater Lihenost om u s virescen s 2 2.0 10 Rufous Whistler Pachycephala rufventris 1 0.3 Grey Shdke{hrush Colluricincla harmonica* 2 0.3 -lark Grallina c1ano I e uc a 1 1.0 7 Rhipidura leucophrys I 1.3 0.8 Cracticus torquatus+ 0 1.3 0 C. nigrogularis* 0 2.8 0 Grey Cunawong S/repera versicolor+ 1 0.3 Ausfalian Raven Coryus coro oides* 13 1.2 10.8 Little Crow C. bennetti* 1.0 9

TABLE 2

Publishedand communicatedaccounts of an associationbetween Grey and PiedButcherbirds with Manorinaspp.

Manorina spp. Details ofAssociation

Noisy Miner mobbing with Grey Butcherbird (Low 1994) not aggressiveto Grey Butcherbird (Dow 1977) Noisy Miner abandonedsites, from which Grey Butcherbirdswere removed (Grey et al. 1997, 1998;M. Grey pers.comm., cited in Loyn 2002) Noisy Miner Noisy Miners were more likely to be detectedin small siteswhere Grey Butterbirds were present(Major el al. 2001) Noisy Miner Grey and Pied Butcherbirdsalong with other large altamids and corvids (and others)were toleratedwithin miner terdtories (Piper and Catterall 2003) Yellow-throatedMiner excludeother birds, but not Grey Butcherbird (Fulton 2004) Yellow-thoated Miner Grey Butcherbird breedingin their colony (Fulton 2004) Yellow-throatedMiner identified that Grey Butcherbirdsand Yellow-throatedMiners clusteredmore closely to each other (in a correspondenceanalysis) than other woodland birds in road verges(Arnold and Weeldenburg1990) Yellow-throatedMiner Yellow-throatedMiners and Grey Butcherbirdshave co-occuned consistentlyat Ejah from 1959 to the present(Stephen Davies pers.comm.) Yellow-throatedand in associationwith Grey Butcherbird, in mallee (E. Moysey pers.comm., cited in Loyn 2002) Black-earedMiner Black-earedMiner breed within close proximity (less than 50 m) to Grey Butcherbird (Rohan Clarke pers. comm.) Black-earedMiner fledglings perchedwith Grey Butcherbird (Mclaughlin 1990) June2008 GF. FuitoriiPossible terdtorial and nesting association betwe€n Pied and Grey Butcherbirds and the Yellow-throated Miner 33

TABLE 3

ObseNations of tolerant behaviour between minels and butcherbirds. Abbreviations: juv. = juvenile, imm. = immature, YTM = Yellow-throated Miner, PBB = Pied Butcherbird and GBB = Grey Butcherbird. Site Observations Ejah Three YTMs perchedwithin 20 cm of an imm. GBB.

Westonia Three YTMs perched-30 cm from, flew with, and then perchedagain 30 cm from the PBB.

A YTM perched within 20 cm from a PBB on a clothes line and called softly with a two note call toward the PBB; I saw no other birds close enough to hear this call.

A juv. PBB and a YTM from the inter-specificgroup of nestsforaged, on the ground for 27 secords, within 30 cm of each other. During this time, the juv. YTM turned its back on the PBB thrce times.

A YTM perched 15 m from an incubating PBB. The PBB stayedon its nest, although when other species(e.9. Red Watdebird) perchednear its nestit would leave the nest and chaseaway the intruder.

A PBB perchedwithin 30 cm of a miner on powedines for 15 seconds;each speciesappeared unconcernedwith the other'sclose proximity.

All four PBBs chasedeach other through and around treesnear their nests,while a YTM perched quietly about 10 m from this activity.

A nesting YTM perched l0 cm from a PBB for 20 seconds,without any display of aggression.

Three PBB foraged between the two YTMS nests within the inter-specihc nest group without attractingaggression; these nests were l0 m aparl,

A nesting YTM from the inter-specificgroup of nestsperched within 10 cm of a juv. PBB and called softly, using a two note call; the YTM then stretchedits head toward thejuvenile PBB coming close enough to touch beaks, less than or equal to 1 cm apart. Neither bird reacted in alarm from the closenessand the YTM moved past the juv. PBB (within l0 cm) and with its back to it.

building a nest, at Ejah, within the area defended by miners 1998; Recher 1999, 2004; Ford et al. 2001; Fulton and Ford (Fulton 2004). Nesting Yellow-throatedMiners may have 2001; Piper and Catterall 2003). Further insights into a benefitedfrom PiedButcherbirds that chasedAustralian Raven, possible associationbetween miners and butcherbirdsmight Red Wattlebird, Western Corella and Galah ftom the inter- €xplain how one or both species exploit this habitat, an specific group of nests at Westonia, although the Pied outcome that might assist in managementof these small Butcherbirdsmay haveonly beendefending their own nests.A11 remnantsfor conservation. the birds chased from this area were large and the two former speciesare known nest-predato$(Brown and Brown 1986; ACKNOWLEDGMENTS Majar et al. 1999; Fulton 2006a, 2006b). Nest predators arc not I thank the following organisationsfor supporting and funding my usually toleratednear nests of birds (e.g. Pavey and Smyth research: Curtin University of Technology, Department of 1998;Amold 2000b;Fulton unpub.data). On three occasions Environmental Biology, at Westonia; the Cenhe for Ecosystem that birds had not been chased away by aggressive Yellow- Management, Edith Cowan University; and the Department of thrcated Miners they were subsequentlychased away by Pied Conseflation and Land Management, at Ejah. I acknowledge my Butcherbirds. supervisors Harry F. Recher and Piere Horwitz.

I propose that butcherbirds may benefit from larger This study was bom out of a workshop held at the Southen inve ebrates that are unused and controlled by miners Hemisphere Omithological Congress, in 2000, chaired by Richard throughthe exclusionof other insectivoresand that both birds Loyn, and from discussionswith Doug Dow at the Austmlian may benefit from grouping and jointly defendingtheir nests. Omithological Congress,in 2003. The following individuals supported my researchin various ways: This assumption could be tested by correlating the nest- Prof. StephenDavies and Prof. Jonathan Majer who facilitated my field trips and provided encouragement: successof both generato the distancesbetween their nests. Richard Loyn, StephenDavies and Mike Clarke made corEnents on the Miners, in particular, have been identified colonising and manuscript as did Cole/ld's reviewe$ Ian Rowley and Eleanor Russell. excluding other birds from many small forestsremnants and I acknowledge the traditional owners of the land where my roadside strips, which is a factor in the decline of many obseflations werc made: at Ejah the Watagee pegple and at Westonia woodlandspecies (Arnold and Weeldenburg1990l' Grey et al. the Kalaamayapeople. 34 G.RFulfon; Possible territorial and nesting association between Pied and Grey Butcherbirds and the Yellow-throated Miner Corella32(2)

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