BREEDING THE BLACK SPARROW HAWK ACCIPITER MELANO- LEUCUS IN CAPTIVITY by A. Brosset LaboratoireD'Ecologie Tropicale LaboratoireD'Ecologie Generale du Museum 4 Av. du Petit Chateau-91S00Brunoy France

During the springof 1979,a pair of the AfricanBlack SparrowHawk (Accipiterme- lanoleucus)bred in my aviariesin Paris.Events from buildingof the nestto fledgingof the youngwere followed, with a televisioncamera in the aviaries. TropicalAccipiters have rarely, if ever,been bred in captivity.In the presentcase, the parentbirds were not takenfrom a nestbut were trappedas free-rangingindivid- uals;at leastthe femalehad probablyhad previousbreeding experience in the wild. Thus artifactsdue to captivitywere minimalin the behaviourof this pair. Finally, thanksto the televisioncamera, it was possible,without disturbingthe birds,to seein detailsequences of behaviourthat are extremelydifficult to observein the field from a blind.

Originof thebirds The two birdswere caughtnear Makokou,northeastern Gabon (1 lat. N.--12 long). The speciesis not rare in thisarea of heavyrain forest,and as elsewhere,is notoriousas a poultry-thief.To protecttheir farmyards,the nativestrap thesehawks and, during the past15 years,14 specimens,dead or alive,were brought to me. I sawthis bird quiteoften in the field, but alwaysbriefly. In Gabon,as in eastAfrica (LeslieBrown, pers. comm.)the speciesfeeds mainly on pigeons.I observeda male catchinga largedove (Turtur brehmeri) and anotherone a pigeon(Columba unicincta) asbig asitself. A femalewas seen carrying a largepigeon, and another pursuing a group of greenpigeon (Treron australis). The pigeonswere attackedfrom high trees,on the borderof abandonedcultivations, while feedingon the fruits of low bushesof Solanum torvum.In one case,a groupof pigeonswas attackedabove a large river by a female stoopingfrom the sky,like a peregrine.The pursuitsI sawwere longer,more persistent, andprobably faster than those observed in Europeanaccipiters. In the unbrokenrain forestof Gabon,the nestsof four speciesof localAccipiter-A. melanoleucus,A. tousseneli,A. castaniliusand A. erythropus-areespecially difficult to find, and althoughnuptial displays were observedon severaloccasions, in 15 yearswe foundonly a singleeyrie of melanoleucuscontaining a downyyoung in November1979.

Historyof the parentbirds Among the 14 individualsbrought to me, six were alive. They were exportedto France,and trained for falconry.One pair waskept in a doubleaviary, for an attemptat reproduction. The femalewas trapped in April 1971.The bird wasat least4 yearsold, havingthe breastplain white withoutblack streaks, characteristic of the secondand third plumages (pers.obser. on individualstaken in juv. plumage,and kept for more than 3 yearsin captivity).

58 Raptor Research15(9.):58-64 Summer1981 Brosset--BreedingBlack SparrowHawk 59

After 18 monthsof captivity,the moult,which was synchronized with the Gabonaus- tral cycle (November-April),became, in Paris, synchronizedwith the boreal cycle (April-September)and was maintained for 6 years. From 1971 to 1976, this hawk wasused for falconry,catching pheasants, and even, thoughrarely, attacking mammals. She caught a domesticcat. This bird was shy,of ir- regulartemper and not as efficientas anotherfemale of the sameorigin, that, after a brilliantcareer in falconry,escaped and became a Wood Pigeon(Columba palumbus) catcheron her own from Juneto December1970 in the smallwood neaJ'Paris where sheestablished her territory. The male was trapped while eating a chickenin February, 1976, when about 3 monthsold. After 14 months,timing of the moult was synchronizedwith the boreal cycle.He wasnot trainedfor falconrybut becamerather tame.

Successiveattempts at reproduction During the springof 1977, the male and the female were put in twin aviaries,sepa- ratedfrom eachother by a pieceof net. Early in June,both birdswere carryingtwigs, in spiteof the fact that the male wasfar from beingadult (he still wore somefeathers of the juvenileplumage). As the femalewas not aggressivetoward the male, we removed the net. Goodrelations were establishedbetween the two, whichcooperated in building a nest.It wasprobably too late in the seasonand no clutch was laid. From this time, theywere maintained together continuously. In March 1978, a new nestwas built by both birds,although no other sexualactivi- ties-vocal or behavioral-werenoticed. The femalelaid a clutch of 3 eggs(first egg on the 1st, secondegg on the 6th, third egg on the 9th of April). After 21 days of in- cubation,the eggs,all infertile, were removed.The female laid a secondclutch of 2 (17thand 20th of May) that werealso infertile. DuringMarch 1979,a new nestwas built by themat the sameplace as the preceding one.A televisioncamera was placed in the aviary,and their behaviournoted from 100 m. During March,much time from dawnto sunsetwas spent in buildingthe nest.Most of the material,branches and twigs,was carried early in the morning.During the day they put the materialin properposition, either with the beak or pushingthe twigswith the breastagainst the wall of the nestcup. Finally the cup was furnishedwith large greenleaves of cherry-laurel,cut from the smalltrees in which the nestwas built. The two birdsbrought material during the entire nestingperiod, especially green leaves, but alsolarge branches, till the time the youngfledged. A clutchof 4 waslaid: sequentiallyon the 27th of March, 1st of April, 4th of April, and 9th of April. The last three eggswere fertile. The first chick hatchedon the 9th of May, the second13 hourslater, the third 5 dayslater. The third chick,although vigor- ous,was not fed, was overpoweredby its sibsand died when 5 daysold. Frequentbat- tleswere observedbetween the two olderchicks, which were the samesize. Finally, one chick stoppedgrowing when 20 daysold, being overpoweredby the other. He was ejectedfrom the nestseveral times by his brother,and on the 6th of Junewas found dyingon the groundwith a bruisedhead. The last young--amale of smallsize-left the nestwhen 46 daysold. A few dayslater, he killed chickens,rabbits and young pheasants in the aviary and two weekslater caughtfree-ranging prey suchas large rats,black- birds,magpies, crow, etc. 60 RAPTOR RESEARCH Vol. 15 No. 2

Behaviorof female The femalewas first placedin the part of the aviarywhere a suitableplace to build a nesthad been prepared.She acceptedthe place and beganto build. After the male ioinedher, both were seenbuilding at the samerate, and in the samemanner. Beforelaying, the femalespent several days in a "preposital"state. She stood quietly on the nest,the ventralplumage hanging vertically; she took practicallyno foodduring this time. Eggswere laid duringthe afternoon.She stayedon them after the first was laid, continuouslyduring the night and by boutsduring the day. The male guardedthe nestwhen the femalewas absent. After the secondegg, incubation became continuous. During the first 10 daysthe incubatingfemale was very excited,changing position an averageof 10 timesan hour,rolling the eggswith the beak and perchingon the border of the nestto arrangetwigs and leaves in the nestingcup. Duringthe last3 weeksof in- cubation,the femalebecame more and more lethargic. The oldestyoung was fed by the female13 hoursafter hatching.The rhythmof feed- ing duringthe first two weekswas, on the average,4 timesa day. The male brought prey (sparrows,doves, pigeons, quails) to the edgeof the nestand remainedperched on it duringthe time the female pluckedthe prey and fed the young.An unexpectedbe- havioroften occurred:the female fed not only the youngbut alsooffered food to the malewho, at leastduring the first week,took much more food for himse|ffrom the beak of the femalethan did the young.Sometimes, the male offeredto the youngsmall pieces of meatgiven to him by the female. From the prepositalto the end of the fledgingperiod, alarm calls were givenby both sexeswhen a potentialenemy was in view. During incubation,the femaleleft the eggs when disturbed,but after the younghatched I was savagelyattacked by her and quite seriouslywounded. Large rats, which were toleratedin the aviarybefore hatching, were killed systematically(but not eaten).These behaviors ceased completely after the young were removedfrom the aviary. The behaviorof the femaletoward the malewas especially mild andfriendly. Mutual facialgreeting was observed. While incubating,the femalewas seen with the male per- chedon her backwith wingsextended in an attemptto shadeher. When the femalewas off the nest,the malealways incubated or broodedeggs or chicks.Within a few minutes the femalereturned and forcedthe male to leave the nestby pushinghim carefullyout of the cup with the bendof the closedwing. The only overt aggressionbetween the two birds is described later.

Behaviorof male The behavioralrole of the malewas more important than expected, especially his role of watcher.He was often the first to give alarm at the approachof a potentialenemy (hiscalls are morerapid, and higher pitched than the female).He took an extremeinter- est in the eventsof reproduction.He was seeninspecting for minutes,and touching carefullywith his beak the first egg and the newly hatchedyoung. When the female left, the male alwayscame immediately onto the nest.His shadingof the incubatingfe- male and of the fledglingswas constantwhen the aviary was in sun.The male carried mostof the prey to the nest. During the first stageof the mating periodhe killed severalyoung wild rats, which werenot eatenbut placedon the higherperches: offerings to the female? At the entranceof an intruderin the aviarythe malebecame very excitedand on sev- Summer1981 Brosset--BreedingBlack SparrowHawk 61

eral occasionsredirected his aggressionagainst his mate: an abnormalbehavior, cer- tainly due to captivity.The femalewas slightly wounded in thismanner so I madeno moreattempts to enter the aviary. The "deflectionof attack" is one of the mostsignificant aspects of human-raptorin- teraction(Olendorff 1971). Nevertheless, no instanceof an irate hawk attackingits mate whena humanis closeto the nesthas been recordedpreviously.* Behaviorof young We clearlysaw the newlyhatched young taking small pieces of foodfrom the beak of the mother(this is not the casein the genusFalco, where the newly hatchedyoung begs foodin a passerinemanner, Brosset 1973). Our observationsof youngat the nestwere not significantlydifferent from the numer- ousobservations made on youngraptors in the wild exceptfor the extremeaggressive- nessof the chicks toward each other. Furious battles, with blows on the heads of the sib- lings,were frequentfrom the first daysafter hatching.This resultedin the lossof two of threeyoung. The younghad muchmore food than they couldeat and the lack of food hadnothing to do with this "cainism." This behavioris perhapsmore developedin the westernpopulation of the species than in the easternpopulation, where L. Brown (pers.comm. and 1980) saw several broodsof two andthree youngin Accipitermelanoleucus. By contrast,in 3 caseswe saw in Gabon (one brood in the wild, one in captivity, and parentsfollowed by a single young)only one young was fledged. At the sametime we sawfor severalspecies of birds that the rate of reproductionseems lower in westernAfrica than in the east(Brosset, in press).Perhaps the caseof the BlackSparrow-hawk follows the generalrule not through a smallerclutch size, but throughmore frequent"cainism." Generalremarks on thisexperiment A singlecase does not permit generalizationand we give here only rough selected data,their interestbeing that they havebeen rarely, if ever, recordedin the field. Sexualmaturity We have no informationon the attainmentof sexualmaturity in females,the only fe- malewe testedhaving been caught as fully adult. We kept in captivityfor more than 3 years2 malescaught as juvenilesin Gabon. Thesetwo malesbecame sexually adult when three yearsold. One wasobserved calling andcarrying branches when about 38-40 monthsold; the otherproduced young for the first time when 40 months old. Mostspecies of raptorsbecome sexually mature later in captivitythan in the wild. On the other hand, the two maleswe observedhad to resynchronizetheir moult cycle, whichwas initially austral,to the borealcycle. Perhapswild individualsare adult earlier,when two yearsold. This wouldbe easyto verify in the wild, sincethe secondplumage following the first immatureplumage is characteristicin the Gabonesepopulation of the species. We noticedconsiderable differences in the sexualcalling of the two malesat the on- setof sexualmaturity. One wasextremely vocal, the other quite completelysilent. Nestbuilding A first autumnalbout of buildingtook place in November1978. Much material was broughtonto the placeof the nestwithin a week.Then building stopped completely till *Ed. Note: Female peregrines (Falco peregrinus) have been seen to "chase" their mates away from eyries in "aggressive"manner while investigatorsare at eyries. 62 RAPTOR RESEARCH Vol. 15 No. 2

the first daysof March 1979 (autumnalcarrying of nestmaterial is commonin certain palearcticspecies-such as the HouseSparrow (Passer domesticus) in Paris). The rate and techniqueof buildingwas similar in male and female.We may insiston the importantrole of greenleaves which were brought till the endof the fledgingperi- od. Thisrole, subiectto somespeculation (Olendorff 1971) seems perfectly clear to us.A layerof largegreen leaves protects the eggsand the youngchick against the risk•f slip- pingbetween the interlacingtwigs in the bottomof the cup (L. Brown1953). This inter- pretationis not speculativeat all. For example,during the first attemptat reproduction, in 1978,when we did not securegreen leaves for them,two eggsbecame entangled in the body of the nestin a positionin which the parentbirds were unableto incubateor evento recoverthe eggs.I sawthe samephenomenon in the wild. In easternMorocco, on a "Betoumtree" (Pistaciaatlantica) I discovereda nest of the SerpentEagle (Cir- cactusgallicus) with a non-incubatedegg encrustedin the body of the nest.The eagle wassetting on a secondegg, half incubated,laid in the samenest where the first was lost. We sawthe femaleseveral times taking away, from below the young,fouled green leaves,shaking those leaves outside the nest,and replacingthe sameleaves in the bot- tom of the nestunder the young:sanitary behavior which has perhapsnot been ob- servedbefore in any species.

The clutch In 1978,the first infertile clutch of 3 eggswas removedafter 21 daysof incubation. The femalelaid a secondclutch of 2 eggs,also infertile, 20 dayslater. In the three clutcheslaid, the first eggwas the mostelongated, slightly blotched with palegreenish-brown, the otherone being plainly colored of pale grey-green:exactly the colorof EuropeanGoshawk (Accipiter gentilis) eggs. In the third clutchof 4, only the first eggwas infertile. In eachclutch, the intervalbetween eggs was 3-5 days.The incubationperiod was 34 daysfor the 3 fertile eggs.Two chickshatched in the afternoon,the other early in the morning. We sawhow egg shellsdisappeared from the nest.The birdsdid not take the shells away,as most birds do: the femalecrushed the shellswith her beak and the smallbroken piecesfell and disappearedbetween the interlacedsticks of the nest.

The moult In the 1979breeding season, the moultbegan 3 weeksearlier than in precedingyears. In bothmale and female, loss of the first featherstook placeduring the time the female was laying.Although food was given "ad libitum," the moult stoppedcompletely for both duringthe entire rearingperiod, and startedagain when the fully fledgedyoung were removedfrom the pen. The moultwas completed two monthslater than the pre- cedingyears (an artifact due to captivity?-ora stoprelated to productionof young?).

Feedingbehavior We sawnothing remarkable except during the first two weeksof brooding,the nest waskept perfectlyclear of prey remainsor non-consumedprey. Betweenbouts of feed- ing, prey remainswere invariablycarried away, usuallyonto perchesand put againon the nestonly duringfeeding time. When the youngwere able to feed themselves,this Summer1981 Brosset-BreedingBlack SparrowHawk 63 behaviorceased completely and remains of prey, evenrotten ones, were spreadover the rim of the nest,without being removed by the parents. Thisbehavior is not specialto tropicalspecies of Accipiter (Olendorff1971). In equa- torial forest,.where predacious animals are abundant,the remainsof prey on the eyrie mayattract some predators of eggsand young chicks, and the removalby the parentsof non-consumedprey from the eyrie may be of survivalvalue for the brood.When the youngis capableof self-defense,the adultwould cease to keepthe nestclean of remains of prey.

Intersexual behavior Literatureconcerning behavior of the Accipiterin captivity,especially as relatedto breedingattempts, is full of murderstories, the femalekilling her "husband."In fact, mostof theseattempts were madeby falconerswith eyessesimprinted on Man, birds that do not recognizethe nestpartner as belonging to their own species.In manybirds, the knowledgeof a conspecificis not innate but is precociallyacquired through the view of the parents.For the imprintedlarge femalehawk, the smallmale is no more thanan item of prey,and is treatedas a pigeonor a chicken. We may believethat the intersexual behavior of individualstaken in the wild as adultsor sub-adultswould give a better picture of what really occursunder natural con- ditions.In fact, in thispair of BlackSparrow Hawks, where the male wasa "passager" andthe femalea "haggard"(in falconers'terms) we did not seeany fear behaviorin the malenor anyaggressive behavior in the female.

Conclusion We are fully convincedof the lesservalue of data obtainedin captivity,compared with similardata obtainedin the field. Nevertheless,where birds are kept in conditions as closeas possibleto natural,continuous observation in fidl view with the help of a magnetoscopeor a televisioncamera allow oneto collectvaluable data which would be very difficultto obtainotherwise in the wild from a blind. Comparisonsbetween data obtainedin the field and in captivityshould permit one to perceiveand to understand morefully the sequenceof breedingbehavior in the raptors.

Literature Cited Brosset,A. 1973. Etude comparativede l'ontogenesedes comportements chez les Ra- pacesAccipitrides et Falconides.Z. Fur Tierpsychol.32: 386-417. Brown,L. H. 1953. On the biologyof the large birds of prey of the Embu District, Kenyacolony. Ibis 95: 74-114. Brown,L. H. and D. Amadon.1968. Eagles, Hawks and Falconsof the World. Country Life Books, Great Britain, 2 vols. Brown,L. H. and B. E. Brown.1979. The behaviorof the black sparrowhawk(Accipiter melanoleucus).Ardea 67: 77-75. Olendorff,R. R. 1971.Falconiform reproduction; A review.part 1. The pre-nestlingpe- riod.Raptor Research Report 1, RaptorResearch Foundation. 64 RAPTOR RESEARCH Vol. 15 No. 2

Fig. 1. The pair of GabuneseBlack Sparrow Hawks at the nest.

ANNOUNCEMENT-MEETINGS COMING UP

InternationalGoshawk Conference The InternationalAssociation for Falconryand Conservation of Birdsof Preyis or- ganizinga conferenceon Understandingthe Goshawkat the Departmentof Zoology andWadham College, Oxford, from September29 to October1, 1981.The conference will providea reviewof recentresearch findings in sessionson Systematicsand Popu- lationDynamics, on Predation and Management, and on Falconryand DomesticBreed- ing.There will be half-hourpapers by mainspeakers from Britain, Finland, Germany, Holland,Poland, Sweden and the United States and the proceedings will be published. Bookingforms may be obtained by sendinga stamped, self-addressed envelope to:

Dr. R.E. Kenward MonksWood ExperimentalStation AbbotsRipton HUNTINGDON PE17 2LS England