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ORNITOLOGIA NEOTROPICAL 20: 147–151, 2009 © The Neotropical Ornithological Society

FIRST NESTING RECORD OF THE WHITE-BROWED ( KUHLI) FROM THE MADEIRA-PURUS INTERFLUVIUM, BRAZILIAN AMAZONIA, WITH SOME REMARKS ON PLUMAGE VARIATION

Guy M. Kirwan

74 Waddington Street, Norwich NR2 4JS, UK. E-mail: [email protected]

Primer registro de nidificación de Gavilán de Ceja Blanca (Leucopternis kuhli), del interfluvio Madeira-Purus de la Amazonia brasileña y algunas notas sobre la variación del plumaje.

Key words: White-browed Hawk, Leucopternis kuhli, nesting, Brazilian Amazonia, plumage variation.

The exclusively Neotropical Leucopternis and most widespread of these, the White Kaup, 1847, comprises ten of Accipi- Hawk (Leucopternis albicollis), are comparatively tridae principally distributed over Middle few compared to any raptor breeding in tem- America and the northern half of South perate regions. The only detailed observations America, although two species are restricted on any member of the genus are those by to the Atlantic Forest region of southeast Draheim & Aguirre (1992) and Draheim South America (Bierregaard 1994, Ferguson- (1993), who reported on six nests of L. albi- Lees & Christie 2001). It is a generally poorly collis that they discovered in Guatemala, and known and apparently polyphyletic collection Gelis & Greeney (2007), who described a of raptors (Amaral et al. 2006); three of the nesting record of (L. princeps) in genus were deemed to be high research prior- northeast Ecuador. To date, nothing is known ity by Parker et al. (1996), and, of the rest, five concerning the breeding of the Slate-colored were stated to be of medium priority by the Hawk (Leucopternis schistaceus) of Amazonia, same authors. BirdLife International (2008) the (L. plumbeus) of eastern currently treats one species as Endangered, Panama to northwest Peru, the Black-faced another as Vulnerable, and two as Near Hawk (L. melanops) of the Guianan Shield and Threatened. Furthermore, breeding data for eastern Amazonia, the White-browed Hawk the entire genus are notoriously few. In their (L. kuhli) of Amazonia, the White-necked general surveys, Bierregaard (1994) and Fer- Hawk (L. lacernulatus) of eastern Brazil, and guson-Lees & Christie (2001) were able to list the (L. polionotus) of the Atlan- nesting information for just four species, and tic Forest region. Here I present the first even the available data for the best known breeding data for L. kuhli, which species is

147 KIRWAN generally considered to range from lowland Nest. In the late afternoon of 18 December I eastern Peru south of the Amazon and discovered an inconspicuous nest just 75 m extreme northern Bolivia through north- from the lodge (and c. 50 m from the central Brazil south of the Amazon to eastern favoured tree), and directly above a narrow Pará (Ferguson-Lees & Christie 2001). foot trail. In fact I had walked the same trail without observing the nest on the previous STUDY AREA afternoon. Indeed, the nest was only discov- ered through the chance discovery of an adult During 17 to 23 December 2007, I conducted L. kuhli perched c. 10 m up on the near-verti- ornithological fieldwork at Tupana Lodge, in cal trunk, in the upper midstory, of a canopy the Madeira–Purus interfluvium, Amazonas height tree. After I had watched the for state, Brazil (04°04’S, 50°40’W). Tupana lies c. over 10 minutes the bird flew 5 m to, and 150 km south of Manaus on the BR-319 high- landed on, the previously unseen nest, where- way to Porto Velho, the capital of Rondônia upon it settled as if incubating, or less likely state. Particularly to the east of the road, the brooding (no young was audible or visible in lodge clearing is surrounded by relatively low, the nest), at which point the adult was only closed-canopy, terra firme forest on rather just visible above the nest’s rim. sandy soils with some low-lying and poorly The nest was sited at approximately 15 m drained areas that are seasonally flooded, and above ground, i.e. within the subcanopy of a a canopy height of c. 20 m, though taller canopy height tree, in an area of the forest emergents reach c. 30 m. Large, natural tree- with a particularly dense understory and some fall gaps, some of them > 0.5 ha, are com- palms. Two branches within a major horizon- mon. The understory is dominated by large tal fork of the tree supported the hawk’s nest, areas of dense c. 2 m-tall palms and in places which was an untidy, near-hexagonal structure there are small, less than 2 m-wide, streams. constructed of sticks and some smaller twigs, and ‘adorned’ with a handful of dead leaves RESULTS AND DISCUSSION on its outer walls. From ground level it was impossible to evaluate whether the nest con- The White-browed Hawk was seen on most tained any lining, as has been described for L. days, usually from the lodge itself, where an albicollis (Draheim & Aguirre 1992, Ferguson- ‘upper observation’ deck that is almost at the Lees & Christie 2001). Some sticks were up to same height as the surrounding canopy per- 0.5 m long, protruding from the main walls, mits privileged views of the surrounding area. and c. 6 cm in circumference, and the main One bird, apparently always the same based mass of the nest (i.e. not including parts of on bare-parts coloration (see below), was reg- those twigs that protruded significantly from ularly seen perched, sometimes for quite long the whole) was estimated to have a width of periods of up to 45 minutes, in a particularly 40 cm at the widest point, and a depth of c. 20 tall emergent during the first two hours of cm. These estimated dimensions are smaller daylight. Such behaviour is typical of most than the measured sizes of L. albicollis nests in Leucopternis, including L. kuhli (pers. observ. at Guatemala (Draheim & Aguirre 1992, Dra- Alta Floresta, Mato Grosso, Brazil). The bird heim 1993), which is unsurprising given that was never heard to vocalise, although both the latter is a somewhat larger species (wing this species and L. melanops frequently do so length of female L. albicollis ghiesbreghti 362– when apparently advertising their territories 388 mm vs. female L. kuhli 214–237 mm: Fer- (A. Whittaker pers. com. 2008). guson-Lees & Christie 2001), but larger than

148 KIRWAN those of L. princeps in Ecuador (Gelis & that the species can be quite catholic in its Greeney 2007). The nest was lower off the choice of nesting sites, including on a rock ground than any of the six nests of L. albicollis ledge beside a waterfall. Draheim (1993) con- found by Draheim & Aguirre (1992), which sidered that the young at a nest of L. albicollis might reflect the different hunting strategy in Guatemala would have fledged at the start postulated for L. kuhli (Ferguson-Lees & of the wet season, and young were being fed Christie 2001) but could equally be reflective at a nest in northeast Ecuador during the wet of the overall stature of the different forests. season (Gelis & Greeney 2007). It is impossi- In late August 2008, A. Whittaker (pers. com. ble to know the state and development of the 2008) found an Ornate Hawk-’s (Spizae- L. kuhli nest I observed, but December is tus ornatus) nest with a fully-grown young in already about two months into the wet season the same general area. The presence of this in central Amazonia, and there were regular, species, and the sympatric and larger White heavy and prolonged rain showers every day, Hawk, might have forced the L. kuhli to be usually in the early afternoon, during my stay more secretive than usual in choosing its nest at Tupana. The globally threatened Grey- site. I deliberately refrained from visiting the backed Hawk (L. occidentalis), of western vicinity of the nest again in order to minimize Ecuador and extreme northwest Peru, is also any disturbance, especially as there were no assumed to breed in the wet season, although other visitors at the lodge. there have been no published observations of a nest to date (Ferguson-Lees & Christie Comparison with previous data. Unlike those 2001), except in the grey literature (Vargas nests of L. albicollis reported from Costa Rica 1995). and Trinidad (Stiles and Skutch 1989, ffrench 1991), the nest of L. kuhli was not con- Plumage variation. Amaral et al. (2007) discussed structed on or close to any bromeliads or and clarified the immature plumage of L. other epiphytes, but it was nonetheless dis- kuhli, but my observations at Tupana of two tinctly inconspicuous, even after it had been suggest either more complex age-related located. Stiles & Skutch (1989) considered the or, previously unidentified, sex-related varia- same to be true of nests of L. albicollis. A. tion. The bird attending the nest had very Whittaker (pers. com. 2008) mentioned a nest bright bare-parts colorations, with the orange (stage unknown) found north of Manaus, cere and tarsi having an almost pinkish cast, Brazil, on 21 February 1987, sited c. 35 m up and a single centrally positioned white tail in an emergent tree’s fork, 5 m from the top, band, whilst the other bird had three paler, at the edge of a 100-ha reserve. At least one less bright white, and narrower tail bands, and nest of L. princeps had been ‘concealed’ by epi- much paler, plain yellow bare-parts colora- phytes (Stiles & Skutch 1989). Greeney & tion, as well as apparently overall browner, Nunnery (2006) observed an adult L. princeps but not white-spotted upperparts, unlike the repeatedly carrying food, at a site in north- immature specimens reported by Amaral et al. west Ecuador, but were unable to discover a (2007) and the presumed immature observed nest, despite searching, but subsequently by T. A. Parker and K. J. Zimmer at Alta Flo- Gelis & Greeney (2007) reported on a com- resta, Mato Grosso (Zimmer et al. 1997). Both plete breeding event for this species, and the birds displayed the chief identification charac- unpublished observations of others for L. ters associated with L. kuhli, namely the dark princeps, which (together with the data of crown and short white, but distinct, supercili- Muela & Valdez 2003 from Panama) suggest ary, as well as narrowly but distinctly dark-

149 KIRWAN streaked upper breast and neck sides, which Neotropical buteonine diversification. BMC features separate the species from the similar Evol. Biol. 6: 10. L. melanops. The latter species has recently Amaral, F. R. S., L. F. Silveira, & B. M. Whitney. been found to occur syntopically with L. kuhli 2007. New localities for the Black-faced Hawk (Barlow et al. 2002, Amaral et al. 2007, Wallace (Leucopternis melanops) south of the Amazon River and description of the immature plumage & Petermann 2007). Sexual dimorphism has of the White-browed Hawk (Leucopternis kuhli). not been reported in any species of Leucopter- Wilson J. Ornithol. 119: 450–454. nis (Ferguson-Lees & Christie 2001), making Barlow, J., T. Haugaasen, & C. A. Peres. 2002. Sym- it more likely that the variation I observed is patry of Black-faced Hawk Leucopternis melanops indicative of more complex plumage matura- and White-browed hawk L. kuhli along the tion than had been envisaged to date. Dra- lower rio Tapajós, Pará, Brazil. Cotinga 18: 77– heim & Aguirre (1992) reported an immature 79. apparently remaining in the ter- Bierregaard, R. O. 1994. Family ritory of its parents for at least ten months ( and ): Neotropical species beyond fledging. accounts. Pp. 106–205 in del Hoyo, J., A. The region in which Tupana Lodge is situ- Elliott, & J. Sargatal (eds.). Handbook of the birds of the world. Volume 2: New World vul- ated, between the lower Rio Purus and Rio tures to guineafowl. Lynx Edicions, Barcelona, Madeira, was identified as an area of extreme Spain. importance for birds in an overall survey of BirdLife International. 2008. Threatened birds of the biodiversity of Brazilian Amazonia (Oren the world 2008. BirdLife International, Cam- 2001). Tupana itself makes an excellent base bridge, UK. for further research into the avifauna of this Draheim, G. 1993. Breeding biology of the White poorly known area of Amazonia, especially Hawk in Guatemala. J. Raptor Res. 27: 68. given its relative proximity to the city of Draheim, G. S., & O. A. Aguirre B. 1992. Breeding Manaus. biology of the White Hawk. Pp. 153–162 in Whitacre, D. F., & R. K. Thorstrom (eds.). ACKNOWLEDGMENTS Maya Project: use of raptors and other fauna as environmental indicators for design, manage- ment, and monitoring of protected areas and Foremost, I thank A. Whittaker, for arranging for building local capacity for conservation in my visit to Tupana and sharing information Latin America. The Peregrine Fund, Boise, concerning its avifauna, and Hadoram Shiri- Idaho. hai, for organising and financing the field- Ferguson-Lees, J., & D. A. Christie. 2001. Raptors work. Whittaker and an anonymous referee, of the world. Christopher Helm, London, UK. as well as the editor, A. Weller, contributed to ffrench, R. 1991. A guide to the birds of Trinidad the final text. J. Ribamar and his staff made and Tobago. 2nd ed. Cornell Univ. Press, Ithaca, me a welcome guest at Tupana. D. Calderón New York. and T. Rosenberry kindly assisted with some Gelis, R. A., & H. F. Greeney. 2007. Nesting of literature. Barred Hawk (Leucopternis princeps) in northeast Ecuador. Ornitol. Neotrop. 18: 607–612. Greeney, H. F., & T. Nunnery. 2006. Notes on the REFERENCES breeding of north-west Ecuadorian birds. Bull. Br.. Ornithol. Club 126: 38–45. Amaral, F. R. S., M. J. Miller, L. F. Silveira, E. Ber- Muela, A., & U. Valdez. 2003. First report of the mingham, & A. Wajntal. 2006. Polyphyly of the nest of the Barred Hawk (Leucopternis princeps) hawk genera Leucopternis and (Aves, in Panama. Ornitol. Neotrop. 14: 267–268. Accipitridae): multiple habitat shifts during the Oren, D. C. 2001. Biogeografia e conservação de

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aves na região amazônica. Pp. 97–109, 456–465 birds of Costa Rica. Christopher Helm, in Capobianco, J. P. R., A. Veríssimo, A. Mor- London, UK. eira, D. Sawyer, I. Santos, & L. P. Pinto (eds.). Vargas, H. 1995. Food habits, breeding biology and Biodiversidade na Amazônia Brasileira: status of Gray-backed Hawk (Leucopternis occi- avaliação e ações prioritárias para a conser- dentalis). M.Sc. thesis, Boise State Univ., Boise, vação, uso sustentável e repartição de benefí- Idaho. cios. Instituto Socioambiental, São Paulo, Wallace, G., & P. Petermann. 2007. A photographic Brazil. record of Black-faced Hawk Leucopternis mela- Parker, T. A. III, D. F. Stotz, & J. W. Fitzpatrick. nops in southern Amazonia. Cotinga 27: 83–84. 1996. Ecological and distributional databases Zimmer, K. J., T. A. Parker III, M. L. Isler, & P. R. for Neotropical birds. Pp. 131–436 in Stotz, D. Isler. 1997. Survey of a southern Amazonian F., J. W. Fitzpatrick, T. A. Parker III, & D. K. avifauna: the Alta Floresta region, Mato Moskovits (eds.). Neotropical birds: ecology Grosso, Brazil. Ornithol. Monogr. 48887–918. and conservation. Univ. of Chicago Press, Chi- cago, Illinois. Stiles, F. G., & A. Skutch. 1989. A guide to the Accepted 23 January 2009.

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