Corella,1995, 19(4): 115-117

CO-OPERATIVECARE IN THE SINGINGHONEYEATER virescens

MICHELLE T. CHRISTY

Division of Earth and Environmcntal Scicnccs.Australian Muscum. 6 Colleee Street. Svclnev.NSW 20U0

Received20 August,1994

A rehabilitatedjuvenile Singing Lichenostomus yirescens was observedin a suburban garden,approximately 15 km from its place of hatching,for 11 days. The juvenilewas visitedby at leastone adultSinging Honeyeater more than 20 times,and was fed on nineoccasions. In addition, a distractiondisplay involving three adult Singing was observed.This is the firstpublished indicationof co-operativecare in the SingingHoneyeater.

INTRODUCTION advantageousto a helper to tend a nest in its home range to reduce the attraction of predators Co-operative breedins. a relativelv rare to the area (Caraco and Brown 1986). behavicjur,is defined as a"reproductivesystem in which one or more individuals of a social group care for offspring that are not their own (Stacelyanb METHODS Koenig 1990). Sixty-five Australian species, Singing Honeyeaters Lichenostomus virescensare common of 20 families, are known to be co-operative over most of Australia west of the Dividing Rangc in wood- brceders, although some have been infrequently land and scrublandhabitats (Longmorc 1991).On 12 August or inconclusivelydocumented (Dow l9B0a). Of 198t1,I was given a five day old Singing Honeyeatcr nestling these,more than five honeyeaters(Meliphagidae) to rehabilitate. The age of the nestling was dctermined by the actual hatching day. It had been rcjccted are regarded as well documentcd on 11 August 1988 or regular from its ncst in a suburban garden in Lynwood, Western Aust- communal breedcrs,while over eight species-have ralia. Three attempts were made to placc the young bird back only been recorded once or twice (e.g. Dow in the ncst, but eachtimc thc parent rejectedit. I banded 1980a; Boles and Longmore 1981). Atthough it thc young bird rcd on the left leg, blue on the right leg (known has been suggested that communal breeding as RB hercafter) and relocatcd it about 15 km away in permits individuals of a species to increase Kenwick, Western Australia, again in a suburban,but narivc, garden. RB was housed temporarily in a small metal-barred reproductive output at times when conditions are cage (60 cm x 45 cm x 40 cm) and kept primarily insidc the favourable (Rowley 1965; Harrison 1969), Dow house until it was 12 days old- RB was fed initially on a (1980b)concludes thcre is no evidenceto support commercially available nutrient mixturc (C'ornplan) plus the claim. honey for the first four days, then supplemented with hand caught invcrtebrates for thc following six days. The cage was Therc have been many suggestionsfor the put outside for a fcw hours during the day from 19 August evolution of co-operative care. Williams (1966) 1988. RB was left in the cage until 24 August 1988, after and Price et al. (1983) propose that helping is which it was placed on top of the cage during the watch misdirected parcntal care. It would be expecied, periods. I made observations from insidc the housc looking if this were out of a window at the watch area. Time of day of observations the case. that the helper would and total number q'ere indiscriminately of observation hours rccorcled. as wcll respond to any beggingyoung of as all observations within a 20 m x 20 m area (Table l). any speciesin the same vicinity. Reyer (1980) suggeststhat helping at a nest may increasethe OBSERVATIONS helper's chance of acquiring a mate. It has not been proved, however, whether those individuals Although I did not seean adult SingingHoney- who give assistanceto a pair are more likety to eater interacting with RB until the latter was 16 be selectedto mate than those who have offered daysold (Table 1), there was evidenceof attempted no assistance(Clarke 1989). If begging young feeding two days before. Various dead inverte- increasethe likelihood of predation, it would be brates were observed scattered on the floor of M. T. Christy:Co-operative care in the Singing Honeyeater Corella19(4)

TABLE, l

Intcractions bctween adult Singing Honeveater/s and the relocated juvcnile Singing Honcycatcr (RB)

Observer Total No. of feeds No. of visits RB's Detc time hours by adults withoutfeeds location

l 9/8/88 0f1001700 1.5 (, t) ln cagc sporadic 20/{J/E8 07301330 3.-5 U 2 in cage sporadic I I /8/88 073G1030 0.8 (, (, ln caSc sporadic l2lrJ/u8 1622 t700 0.6 0 I rn cage 23/8/88 0700-1000 3.0 I ln cage 2.+/8/t{t 0730-1010 2.6 2 I on cagc l-s/8/88 070(H)920 L--) I 3 off cage 2-5/tt/88 l 600-l7 15 1.2 2 off cage 26lti/uu 065-54800 1.0 0 off cage 26/8/88 I700 1730 0.5 U in bush 27l8/8ri 063G-0700 0.5 U off cage 2.7/8/lJrJ 1730- i u00 0.5 0 U in bush 2t3/8/88 070(H)730 0.5 0 2 in bush 29l8/88 070iH)730 0.-5 0 U not seen 0lJ/9/tr8 17001710 0.2 0 0 off cage TOTALS 19.2 9 l,+

RB's cage. These invertebrateswerc not residues cage. After 26 min., an adult had arrived, and from hand feeding as the cage was cleaned daily immediately RB gave a gaping display. The adult after feeding. At the same time, an adult Singing left. Four min. later an adult returned, carrying a Honeveater was seen daily within 50 m of the fly (Diptera) in its bill, and fed RB. The adult cage.An adult attempted to feed the cagedyoung then hopped to the top of a Callistemon bush bird on 23 August by landing on top of the cage 3 m away, perched for 6 min., then flew out of and dropping the fooclin or near RB's gape while sight. A similar sequcncewas repeated 12 min. RB gave gaping displays. Of four attempts later when an adult Singing Honeyeater flew to observedon that day, only one was successful.A the case with an unidentificd invertebrate in its total clf nine feedins instanceswere recordedover bill, fed RB and left after perching on the same three days. four while RB was in the cage, five Callistemon bush for 2 min. Once the adult while out of the cage (Table 1). An adult, how- departed, no others were observedreturning that cvcr. was present within -5m of RB on eight of day. RB, aged 19 days, was left outside for the the I I observation days. night for the first time. During the following day (26 August) RB was observed hopping and On only one occasion (25 August, 070H)920 h) attempting to hawk. Although an adult was seen wcre there more than one adult in the area with RB, it did not attempt to feed the young adult feed RB on simultaneously.Not only did an bird. RB was observed accompaniedby an adult that day, but distractivebehaviour by three adults until 28 August, after which they were not wzls observed at the time RB was being stalked sighted. However, 11 days later (8 September) a by a domestic cat. This behaviour lasted banded juvenile Singing Honeyeater was seen approximately60 sec.,after which the cai vacated approximately 100m away in bushlandbehind the perched the irrea. The adult birds with RB for property. Since no other singinghoneyeaters had 4 min. while RB gave chirping calls almost been colour banded in the area, I assumed it continuously. Once the adults had moved out of WASRB. sight, I placed RB in the cage and observations ceaseo. DISCUSSION During the afternoon of 25 August, I released I am unaware of any other published account RB after which it remained perched on top of the of co-operative care in Singing Honeyeaters. December,'1995 M. T. Christy:Co-operative care in the SingingHoneyeater 117

Although this account details a captive fledgling identified as using some degree ol communal in an urban cnvironment. the behaviour of the breeding in Australia, it may be of corrsiderable attending adults was not manipulated. It is interest to the development of co-operative care pc'rssiblcthat similar behaviour can occur in the hypothesesin honeyeatersin the futurc. natlrralenvironment. It is highly unlikelyRB was related to the one or more adults that carcd for ACKNOWLEDGMENTS it in the Kenwick garden.The nest in Lynwood I thank Mr Waltcr Boles and Dr Richard I\{ajor for hclpful continued to be tended by two adult Singing comments on a drzrft of this paper. honeyeaters r.rntil a single chick fledged on 24 August 19B8.It would be highly unlikely that the REFERENCES parents ccluld tend both the nest and RB, 15 km Boles, W. E,. and Longmore. W. (1981).Auxiliary at thc ncst apart. nor would it be likely that the adult birds of tlre Blue-faccd Honeycatcr. Corella 5:36. are related to. or from the same social group as, Caraco, T. R. and Brown, J. L. (1986). A gamc botween the juvenilc. It is therefore improbable that the communal breeders: when is food-sharing stal:lc'l J. Theor. helping behaviour displayed was due to kin Biol. ll8:379 393. selection. It is unlikely the bchaviour can be Clarke. M. F. (1989).The pattern of helping in thc Bcll Miner (Manorina explained simply as a response to a begging melanophrys). Ethology 80: 292-306. Dow, D. D. (1980a).Communally breeding Australian displaybecause of the ongoing presence birds of several with an analysisof distributionaland environmcntalfactors. adults feeding and exhibiting distraction Emu 80: 121-140. behaviour. Dow, D. D. (1980b). Systems and strategiesof communal breeding in Australian birds. Proc. Internat. Ornithol. It appearsmost probable that the observations Congr. l7:87-5 BBl. documcntedwere a result of misdirectedparental Harrison, C. J. O. (1969). Helpers at the nesr in Ausrralian care (Williams 1966).While no nest was found in birds. Emu 69: 3G-40. 'Honeycaters the study area or immediate surrounds,it may be Longmorc, W. (1991). and their Allics of possiblethat thc adultstending RB were breeding Australia.' (Angus and Robertson: North Rydc.) Price, T.. Millington, S. and Grant, P. (l9ll3). in the area. Therefore, if a highly dependentnest- Helping ar rhc ncst in Darwin's finches as n.risdircctedparcntal care. Auk ling is placedwithin the home range of potentially 100:192-19.1. breeding adults, it is possible that misdirected Reyer, H. U. (1980).Flcxible helpcr structurcas an ecological parental care could result. However, given that adaptation in thc Pied Kingfisher (Cery-lentdis rudi.s L.). three adults wcre seenfeeding and defending thc Behav. Ecol. Sociobiol. 6: 219-227. nestling, it is likely thar this species may well Rowley, I. (1965). The life history of the superb bluc wren, Malurus cyaneus. Emu 64: 251-291. breed co-operativelyin the wild at times. 'Co-operativc Stacey,P. B. and Koenig, W. D. (1990). Breed- A study of Singing Honeyeater behaviour in ing in Birds: Long-tenn Studiesof Ecology and Behaviour.' (Cambridge the natural environment could reveal ifoccurrences University Press:Cambridgc.) Williams, G. C. (1966). Natural selection, of co-operativecare existwithin the thc cost of repro- species.Since duction, and a refinement of Lack's Principle. Am. Nat. only a few speciesof Meliphagidae have becn 100: 687-590.