j RaptorRes. 35(3):235-239 ¸ 2001 The Raptor ResearchFoundation, Inc.

DISPERSION, HABITAT USE, HUNTING BEHAVIOR, VOCALIZATIONS, AND CONSERVATION STATUS OF THE HARPY EAGLE (HARPYOPSIS NOVAEGUINEAE)

MARK WATSON 1 ThePeregrine Fund, 566 W. FlyingHawk Lane,Boise, ID 83709 U.S.A.

SMITH ASOYAMA HerowanaVillage, c/o Researchand ConservationFoundation, Box 1261, Goroka,Eastern Highlands Province,

ABSTRACT.--Westudied the dispersion,habitat use, hunting behavior,vocalizations, and conservationstatus of the New Guinea Harpy Eagle (Harpyopsisnovaeguineae) from December 1998-October 1999 in Crater Wildlife ManagementArea (CMWMA), EasternHighlands Province, Papua New Guinea. Based on territorymapping, we estimatedthat the meanhome rangesize was 13.0 + 3.9 km2 (+SD, N = 5). One pair we followedfor 42 d overa 4 mo periodused an areaof only0.25 km'•. We followedthe malehunting in this area for 6 d (510 min). A smallsample of prey items included ground-dwellingspecies such as forest wallaby(Dorcapsulus sp.), juvenile Dwarf (Casuarius bennett,), New GuineaMegapode (Megapodius decollatus),and an arborealmarsupial. Eagles called mainly during daylighthours, mostly near sunup.Spec- trogramanalysis indicated there were two main calls.A continuous,low frequency,far-carrying call that was used to advertiseterritories and for contactbetween mates over distances<2 km and a higher frequency, chicken4ikecall that was usedin interactionsbetween individuals that were closeto each other and during hunting, perhapsas a stimulusor lure for prey.In contrastto the restof the Highlands,eagles were protected insideCMWMA under agreementsbetween villagers and internationalconservation organizations. KEYWORDS: New Guineat]a•y Eagle,,Harpyopsis novaeguineae; Papua New Guinea;;, vocalizations.

Dispersitn, uso de habitat comportamientode caza,vocalizaciones y estadode conservaci6ndel •tguila Harpia de Nueva Guinea (Harpyopsisnovaeguinea) RES0MEN.--Estudiamosla dispersitn,uso de habitat, comportamientode caza,vocalizaciones y estadode conservaci6ndel•t.guila harpla de Nueva Guinea (Harpyopsis novaeguineae) desde Diciembre de 1998--Oc- tubre de 1999 en Area de Manejo de Vida Silvestrede Crater Mountain (AMVSCM) Provinciade Eastern Highlands,Papua Nueva Guinea.Con baseen un mapa del territorio,estimamos el lamario promedio del rangodel hogar:13.0 _+3.9 kan2 (_+SD,N = 5). Una parejaseguida por 42 diasen un periodode 4 meses utilizoun 5tea de 0.25 km2, seguimosal machocazando en estaarea por 6 d•as(510 minutos).Una muestra pequefia de items incluyo especiesdel sotobosquecomo wallabyde bosque (Dorcapsulusspp.), casuarius enanosjuveniles (Casuariusbennett,), megapodos de Nueva Guinea (Megapodiusdecollatus), y un marsupial arboneo.Las •tguilasvocalkaron principalmente durante el d•a, hacia el amanecer.Los analisisdel espectro- grama indicaronque hubo dosvocalizaciones principales. Una continua,con baja frecuencia,que se podla escucharlejos utilizada para marcarel territorioy contacmrlas parejas a distanciasde <2 km y una con una frecuenciaalta, parecidaa la de una gallinaque fhe utilizadaen interaccionesentre individuosque estaban cerca el uno del otto durante la caza,quizas utilizada como estimuloo como sefiuelopara las presas.En contrasteal restode las Highlands,las ftguilasestaban protegidas dentro de AMVSCM b•o acuerdosentre los pobladoresy organizacionesinternacionales de conservacitn. [Traducci6n de C&sarMarquez]

The New Guinea Harpy Eagle (Harpyopsisnovae- Papua New Guinea and Irian Jaya. It is widespread guineae)is a poorly-known,forest eagle endemic to but uncommon throughout undisturbed forests but only two short notes have been published on Present address:The Game ConservancyTrust, Ford- its ecology,one on its vocalizations(Shulz 1987), •ngbridge, Hampshire, SP6 1EH, U.K. and one on its hunting behavior (Beehler et al.

235 236 WATSON AND ASOYAMA VOL. 35, No. 3

1992). Little is known about range-restrictedrap- tors in tropical forests,yet they are among the most threatened speciesand habitats in the world (Bild- stein et al. 1998). The need for more information on New Guinea Harpy Eagle led us to undertake this study.

STUDY .AJ•& AND METHODS We studied New Guinea Harpy Eaglesfrom De- cember 1998-October 1999 in Papua New Guinea. The main study area was in Grater Mountain Wild- life Management Area (GMWMA), which extends for approximately2700 km2 on the south side of the New Guinea Cordillera, in Ghimbu and East- ern Highlands Provinces (06ø40'S, 145ø00'E). GMWMA is approximately85% undisturbedmon- tane forestand 15% villagesand cultivation.Of the forested area, 60% is used for hunting of bush- meat. During our study,there was no seasonalpat- tern of rainfall. The area has been the subject of combined conservation and sustainable develop- ment initiativessince 1994 (Johnson 1997). Field- •• Legend work was carried out in forest owned by Gimi vil- [] call lagers at elevations between 200-3000 m. [] ß sighting Additional field trips were made to the upperJimi Valley (05ø34'S,144ø39'E) and the northeastedge of the Kubor Range (05ø53'S,144ø22'E) in Western Highlands Province and Mount Giluwe (06ø02'S, Figure l. (A) Dispersionof New Guinea Harpy Eagles 144ø00'E)in Southern HighlandsProvince. There, in Grater Mountain Wildlife Management Area based on we interviewed people from Imbongu, Melpa, and sightingsand calls. (B) Location of study area in Papua Jiwaka groups who had different customsand atti- New Guinea. tudes toward the eagle than the Gimi. This allowed us to assessthe impact of hunting on eagle num- bers acrossregions. Prey remains were collected from a recently used We searched for eagles in all suitable habitats. nest and beneath perches. Prey identification was Eagleswere usuallylocated by their distinctive,far- based on comparisonswith skins and skeletonsin carrying calls and were then observed and fol- the University of Papua New Guinea, Port Moresby, lowed for as long as possible.Locations of eagles Papua New Guinea. were derived using compassbearings from known A 3-yr-old female eagle in the raptor collection points establishedwith a GPS unit and an estimate of The RainforestHabitat Gentre, Lae, Papua New of the distance to eagle perches.When one eagle Guinea was measured and weighed to calculate its wasfollowed or seen severaltimes on the same day, wing loading (Kerlinger 1989). This wascompared this was counted as one sighting. These data were to the wing loading of other species of eagles then plotted with basic topographicalinformation (Brown 1976). using ArcView 3.0 (ESRI Inc. 1994). RESULTS AND DISCUSSION Recordings of vocalizationswere made using a Sony TG-D5 Pro II and Sennheiser ME 66 lnicro- Dispersion. We only found New Guinea Harpy phone. Spectrogramswere made to illustrate each Eagles in CMWMA. Over 212 d, we heard eagles type of call using Canary 1.5.1 software (Cornell calling on 120 occasionsand actually observed Laboratoryof Ornithology 1997). All spectrograms them on 24 occasions for 1002 min. Based on clus- used a sampling rate of 12 kHz on a Hanning win- tering of points where eagles were seen or heard dow of 256 pts with 75% overlap. calling (Fig. 1), we estimated that the area con- SEPTEMBER 2001 NEW GUINEA HARPY EAGI,E 237

Table 1. Prey speciesof the New Guinea Harpy Eagle in Crater Mountain Wildlife ManagementArea (N = 10).

COMMON NAME SCIENTIFIC NAME NUMBER HOW IDENTIFIED

Forest wallaby Dorcopsulussp. 6 bones in nest, pellet Ringtail possum Pseudocheiridae 1 observation Dwarf Cassowary Casuariusbennetti 1 bones in and under nest New Guinea Megapode Megapodiusdecollatus 1 bones in and under nest Fruit-Dove Ptilinopussp. 1 bones in nest rained a minimum of 5 pairs of eagleswith an av- Hawks (Geranospizacaerulescens) (Majnep and Bul- erage home range of 13.0 + 3.9 km2 (+SD, N = mer 1977, Osborne and Osborne 1992). 5). The habitat was not continuous in CMWMA be- Pooling all 40 flights of the six different individ- causeof areas of cultivation around villages,areas ual eaglesobserved, only 4 were >100 m. Similar where suitable prey had been hunted out, and ar- short hunting flights have been described as eas above approximately 2800 m where scrub re- "short-stay perched-hunting" in Northern Gos- placed forest.Accordingly, we estimatedthe overall hawks (Accipitergentilis) in more open habitats densityto be one pair per 150 km• or a total of (Kenward (1982). However,one flight made by a 10-20 pairs in the CMWMA. female eagle was >1.5 km acrossa ravine system Habitat Use. For one pair of eagles,all sightings indicating that New Guinea Harpy Eaglescan trav- and vocalizationswere within a 0.25 km2 area.They el for long distances across the forest. We never were followed for 42 d in May, July, August, and observedeagles soaring, which wascontrary to de- September.During this period, they were not de- scriptions by earlier authors (Rand and Gilliard tected for 8 d which coincided with a prolonged 1967, Brown and Amadon 1968, Diamond 1972, period of heavy rain. It was not clear whether the Peckoverand Filewood1976). The wing loadingof eagleswere still in the area and stayedsilent or had the single captive eagle we measuredwas 0.91 g/ flown to a different area beyond hearing range. It cm• which was 1.3 times greater than valuesre- was remarkable that this pair used such a small corded for other speciesof soaring eagles (Brown area for such a long period. The male eagle used 1976) suggestingthat it is unlikelythat New Guinea the area to hunt and was seen carrying a ringtail Harpy Eaglessoar. Soaring is unlikely to offer se- possum(Pseudocheiridae) at 1610 H on 2 September lectiveadvantage in locatingprey sincethe canopy 1999. restrictsvisibility from the air. However, the sym- Hunting Behavior. Prey items identified from patric but morphologicallydifferent Gurney's Ea- one pellet and other prey remainswere mostlyfor- gle (Aquila gurneyi)was seen soaring 80% of the est wallaby (Dorcopsulussp.) which agreedwith de- time we observedit during our study.Unlike most scriptionsof the diet given by indigenous people raptors that use an aerial display flight in pair (Rand and Gilliard 1967, Majnep and Bulmer bonding and territory defense, the New Guinea 1977;Table 1). Preywere probablytaken both on Harpy Eagles appear to circumvent this by using the ground and within the forest canopy.The ring- an unusual repertoire of calls. tail possumwe observedbeing carried during the Vocalizations. Eagles called mainly during the day suggestedthat, like other nocturnal, arboreal day (Fig. 2) and this agreed with the pattern of speciesin this family, possumswere taken from vocalizations described from September-Decem- their roosting places during the day. We also ob- ber 1986 on Mt. Missim, Morobe Province,Papua served eagles making systematicsearches of suit- New Guinea (Shulz 1987). This finding suggested able roosting placesfor mammalsin the crownsof that most calling coincides with crepuscular and trees. Seven hunters we interviewed described ea- daytimeactivities, including hunting. The mostfre- glesflushing prey from epiphytesor holesby hang- quently-heardcall wasa continuous,low frequency ing from their legsand beating their wingsagainst (<500 Hz) note that has been described as "like a the vegetation. Although we did not observe this plucked bowstring" (Fig. 3a, Diamond 1972). Two behavior, it has been described twice in the litera- other calls had a much higher frequency (1400- ture, and is comparableto techniquesused by Af- 1600 Hz) and sounded like a variable "chuck rican Harrier Hawks (Polyboroidestypus) and Crane chuck" (Fig. 3b, 3c). Both of these callswere heard 238 WATSON AND ASOYAMA VOL. 35, No. 3

'• lO '• 5 z 0 I i I I I I I I I I I 1 I I I • I I I I I I I I

1 3 5 7 9 11 13 15 17 19 21 23

Figure 2. Frequency distribution of New Guinea Harpy Eagle calls by time of day, all individualscombined (N = ! 20). only from one pair with the first call given by the female and the secondgiven by the male. A fourth call was a combination of the "plucked bowstring" and "chuck chuck" calls (Fig. 3d). The low frequency call was audible up to 2 km away. Low frequency, continuous calls propagate much more effectively through foliage, so this call may have been used as a territorial advertisement. Strategies of resource partitioning and reproduc- 4 tion differ between temperate and tropical birds. In the tropics, where resources are more stable, kHz :• •-: territories are often defended year-roundand pair ¾'. bonds are more permanent. As a result, both sexes •,•:•..•....• ....•....,•,. .--- •, ::?:•--:•--•.-:•:•. ':•:"'-'•.•. :?•:"-•..'•-' call year-roundto defend food resourcesand main- , , . , , tain pair bonds (Moreton 1996). The high fre- quency call was only used by the male eagle when hunting. This call may possiblybe used as a stim- Figure 3. Spectrogramsof four New Guinea Harpy ulus to flush prey from roosting placesin the can- gle calls from a minimum of 5 individuals: (A) N = 63; opy or to lure prey in a manner similar to that used (B) N= 23; (G) N = 16; (D) N = 13. by Northern Shrikes (Lanius excubitor,Atkinson 1997). were interviewed at Mt. Giluwe, the upperJimi Val- Conservation Status.There was a sharp contrast ley, and the Kubor Range reported that New Guin- in the attitudes of villagerstoward the New Guinea ea Harpy Eagleswere rare in their forest. A study Harpy Eagle between CMWMA and other areas in of the use of bird plumes among indigenous cul- Southern and Western Highlands Provinces. In tures showeda decline in the frequency of feather CMWMA, eagles were not hunted and were pro- trading (Healey 1990). While our results did not tected under agreementslinked to sustainablede- allow us to assessdirectly the effects of hunting on velopment initiatives made with conservation or- the statusof the eagle populations in these areas, ganizations. However, in the other areas, eagles we feel that a reduction in hunting pressure and were still hunted for their feathers which are used traditional resource extraction through conserva- as symbolsof rank and for personal decoration at tion agreements such as those already in place in ceremonies. In one Melpa village, feathers of four CMWMA are essential to the conservation of the eagles shot within the preceding 18 mo were dis- New Guinea Harpy Eagle. played and, in another two Imbongu villages,reli- ACKNOWLEDGMENTS able accountswere given of eaglesbeing killed us- We are grateful to The Peregrine Fund, Zoological So- ing slingshotsor shotguns.Fourteen hunters who cietyof San Diego, Chew'onCompany, and The Wait Dis- SEPTEMBER 2001 NEW GUINEA HARPY EAGI.E 239 ney Company Foundation for generous financial sup- case study of the Crater Mountain Wildlife Manage- port. We also thank The Research and Conservation ment Area. Pages391-428 in C. Filer [ED.], The po- Foundation of Papua New Guinea and the staff of the litical economy of forest management in Papua New Library of Natural Sounds, Cornell University. Guinea. National Research Institute, lIED, Hong LITERATURE CITED Kong, China. KENWARD,R.E. 1982. Goshawk hunting behavior and ATKINSON,E.C. 1997. Singing for your supper:acoustical range size as a fimction of fbod and habitat availabd- Duringof avian prey by Northern Shrikes. Condor99: ity. J. Anim. Ecol. 51:69-80. 203-206. KERIJNGER,P. 1989. Flight strategiesof migrating hawks BEEHLER,B.M., W. CRILL, B. JEFFERIES,AND M. JEFFERIES. Univ. Chicago Press,Chicago, II. U.S.A. 1992. New Guinea Harpy Eagle attempts to capture a MAJNEP,I.S. AND R. BULMER.1977. Birds of my Kalam monitor lizard. Emu 92:246-247. Country. Auckland Univ. Press,Auckland, New Zea- BlEDSTEIN,K.L., W. SCHELSKY,J. ZALLES,AND S. ELLIS. land. 1998. Conservation statusof tropical raptors.J. Raptor MORETON,E.S. 1996. A comparison of vocal behavior Res. 32:3-18. among tropical and temperate passerinebirds. Pages BROWN,L. 1976. Eagles of the world. David and Charles, 258-268 in D.E. ga'oodsma and E.H. Miller lEDS ], Newton Abbot, Devon, U.K. Ecology and evolution of acousticcommunication m -- AND D. AMADON.1968. Eagles, hawks and falcons birds. Cornell Univ. Press, Ithaca, NY U.S.A. of' the World, Vol 2. Hamlyn, London, U.K. OSBORNE,T. ANDL. OSBOP,NE. 1992. New Guinea Harpy CORNELLLABORATORY OF ORNITHOLOGY.1997. Canary Eagle and Gurney's Eagle Aquila gurn¸,i. Aunt. Raptor acousticanalysis software, version 1.5.1. Cornell Lab- Assoc. News 13:14. oratory of Ornithology, Ithaca, NY U.S.A. PECKOVER,W.S. AND L.W.C. FILEWOOD. 1976. Birds of DIAMOND,J.M. 1972. Avifauna of the eastern highlands New Guinea and tropical . Reed, Sydney,Aus- of New Guinea. Nuttall Ornithological Club, Cam- tralia. bridge, MA U.S.A. RAND, A.L. AND E.T. GILLlARD. 1967. Handbook of New ESRI iNC. 1994. Arcview, version 3.0. Esri Inc., Redlands, Guinea birds. Wiedenfeld and Nicholson, London, CA U.S.A. U.K. HEALEY,C. 1990. Maring hunters and traders:production SHULZ,M. 1987. Temporal variation in the frequency of and exchange in the Papua . vocalisationsof the New Guinea Harpy Eagle. Emu87 Univ. California Press,Berkeley, CA U.S.A. 257-258. JOHNSON,A. 1997. Processesfor effectingcommunity par- ticipation in the establishment of protected areas: a Received27 October 2000; accepted19 April 2001