THE WILSON BULLETIN A QUARTERLY JOURNAL OF ORNITHOLOGY Published by the Wilson Ornithological Society VOL. 111, NO. 4 DECEMBER 1999 PAGES 457-630 Wilson Bull., 11 l(4), 1999, pp. 457-464 A NEW SPECIES OF HAWK-OWL NINOX FROM NORTH SULAWESI, INDONESIA PAMELA C. RASMUSSEN ’ ABSTRACT-A distinctive new species of hawk-owl, Ninox ios, is described from a specimen collected in 1985 in forest at 1120 m in Bogani Nani Wartabone (then Dumoga-Bone) National Park, North Sulawesi, Indonesia. It was previously identified as a rufous morph of the Or&e-bellied Hawk-Owl, N. ochracea. Ninox ios is small, predominantly bright chestnut, and lacks facial patterning; it has pink orbital skin, yellow irides, triangular whitish scapular spots, a finely banded and relatively long tail, unusually short, slender tarsi that are feathered for most of their length, and weak claws. Its relationships within the genus Ninox are unclear; it differs in several morphological characters from all other species. Because Ninox ios is only known from one specimen, its distribution and conservation status are unknown; nothing is known of its ecology, but it probably occurs primarily at higher elevations than N. ochracea. Received 14 Dec. 1998, accepted 5 May 1999. For many years two endemic species of the daal netted an almost entirely bright rufous genus Ninox were thought to occur on the cen- Ninox (Frontispiece) in Bogani Nani Warta- tral Indonesian island of Sulawesi. Of these, bone (then Dumoga-Bone) National Park, the Speckled Hawk-Owl (Ninox punctuZutu) North Sulawesi, Indonesia (Fig. 1). He con- primarily inhabits disturbed lowland habitats cluded that this individual represented “a pre- throughout the island (White and Bruce 1986), viously undescribed rufous phase” of N. and is morphologically quite different from ochruceu (Rozendaal and Dekker 1989), and other endemic Indonesian Ninox. The poorly this treatment was followed by Coates and known O&e-bellied Hawk-Owl [N. ochrucea Bishop (1997). (= perversu)] of the lowland rainforests in While working on small owls at the Na- North and Central Sulawesi (White and Bruce tional Museum of Natural History/Naturalis, 1986) is a small, fairly typical member of its Leiden (NNM, formerly Rijksmuseum van genus (Frontispiece). Because there had been Natuurlijke Historie, RMNH) in June and Oc- no indication that a third species might occur, tober 1998, I chanced to see the rufous Sula- it was a surprise when in 1985 E G. Rozen- wesi specimen, which had been registered as RMNH 84701 but had not yet been incorpo- rated into the main collection following its 1NHB 336 MRC 114, Smithsonian Institution, Washington, DC 20560, and Michigan State University purchase by NNM. On the second occasion I Museum, East Lansing, MI 48824.0590; noted that it differed in several morphological E-mail: [email protected] features from Ninox ochruceu, in addition to t FRONTISPIECE. Cinnabar Hawk-Owl (Ninox ios, upper two) compared with Ochre-bellied Hawk-Owl (N. ochracea, lower left), and Buru race of Moluccan Hawk-Owl (N. squamipila hantu, lower right). Original watercolor painting by Ian Lewington. 457 458 THE WILSON BULLETIN l Vol. III, No. 4, December 1999 Borneo 4- natalis novaeseelandiaessp. .* ’ 118% FIG. 1. Map of Wallacea showing collection locality of the holotype of the Cinnabar Hawk-Owl (Ninox ios), other locations mentioned in the text, and approximate ranges within the region of other species of Ninox and subspecies of W. scutulutu, which occurs throughout the region. the obvious color differences. Subsequent CINNABAR HAWK-OWL Ninox ios sp. nov. mensural analyses of series of all species of Ninox have confirmed the distinctness of the HoZotype.-RMNH 84701, adult male rufous Sulawesi specimen (an adult in good (Frontispiece), according to the label collected condition) in many characters. Although sev- in a forested valley at 1120 m at Clarks’ camp eral Ninox species from other areas are typi- (Hill 1440), east-central Bogani Nani Warta- cally rufous, morphism (and thus true rufous bone National Park, North Sulawesi, Indone- morphs) appears to be unknown for any Ni- sia (ca 0“ 40 ’ N, 123” 0 ’ E) by E G. and C. nox, and in any case most of the differences M. Rozendaal the night of 5-6 April 1985 (the are structural and thus would not be related to label date of 7 April presumably indicates date morph. Despite the fact that only one rufous of death). Label data: “Completely ossified specimen is known thus far from Sulawesi, skull”, “weight 78 g”. there is no reason to believe that any of its Diagnosis.-A small, lightly built, nearly several novel character states are aberrant, and uniformly rich chestnut hawk-owl with a rel- there can be no reasonable doubt that it rep- atively long tail and narrow pointed wings, lax resents a new species. feathering, no facial pattern, mostly feathered Rasmussen l A NEW SPECIES OF HAWK-OWL 459 short slender tarsi, and rufous, narrowly dark- the patterning of its breast feathers, which barred wings and tail. have a light rufous (vs dark brown) area sur- Compared with all flying states of Ninox rounding the whitish shafts. ochrucea [n = 20 (three of which are fully The Philippine Hawk-Owl (Ninox philip- grown juveniles); 6 males, 4 females, 10 un- pensis) superspecies (sensu Dickinson et al. sexed], N. ios is much smaller in most dimen- 1991, but see Collar and Rasmussen 1998) is sions (Table 1, Fig. 2), but has a relatively composed of several dark brown to brown- longer tail and rictal bristles. Its wing, while and-ocher forms that are either barred or shorter than that of N. ochracea, is narrower streaked below. None of the taxa included in and more pointed (Fig. 3). Ninox ios has a N. philippensis can be described as warmer- much shorter, shallower bill and smaller nares toned than rufescent brown. All have much than N. ochrucea. It has short, slender tarsi heavier claws and relatively shorter tails (Fig. that are mostly feathered on both surfaces, 2A) than N. ios, from which they also differ whereas N. ochrucea has longer, stout tarsi in wing shape (Fig. 3). One form, N. [philip- that are largely unfeathered on the anterior pensis] mindorensis (see Frontispiece), is (acrotarsal) side and are virtually unfeathered somewhat similar in overall size and tarsal on the posterior (plantar) side, with numerous feathering to N. ios than is any other taxon, stiff bristles over the unfeathered areas. The including N. ochrucea (Fig. 2C), but not in new species has relatively sparse, fine rufous plumage or the above-mentioned shape char- bristles on the extreme lower tarsi and on its acters. slender toes (although the bristles are heavier All taxa of the paraphyletic Moluccan and longer on the hallux), while N. ochrucea Hawk-Owl (Ninox squamipilu; split provi- has more profuse, heavier, mostly pale bristles sionally into at least three species by Norman (which are usually longer but sometimes worn et al. 1998) are considerably larger and heavi- down to stubs) on the tops and sides of its er-legged than N. ios, and all differ from it stouter toes. Ninox ios has much smaller, more additionally in having whitish-barred under- slender claws that are dark for most of their parts and scapulars. Despite the above differ- length (vs large and mostly pale in N. ochru- ences, Ninox s. huntu (Frontispiece) of Bunt tea). The holotype of N. ios had pink orbital superficially resembles the much smaller N. skin (vs blackish in N. ochruceu) and yellow ios because of its overall rufescence and re- eyes, as does N. ochrucea according to Strese- duced barring below, as well as its obscure mann (1940), who based this statement on G. facial pattern and finely barred tail. The Sum- Heir&hs’ specimens [although Meyer and ba Hawk-Owl (N. rudolji) is large and strik- Wiglesworth (1898) mentioned a brown-eyed ingly different, with a heavily spotted crown, N. ochrucea]. The base of the bill and the cere barred underparts, and broadly banded and of N. ios appear entirely pale (vs the basal speckled upperparts. The widespread and var- two-thirds conspicuously dark in specimens of iable Brown Hawk-Owl (Ninox scutulutu) is N. ochracea). also a much larger species, with a broadly In plumage, N. ios differs conspicuously banded tail and large, heavily feathered tarsi. from both adults and juveniles of N. ochruceu It is dark brown above with the underparts in its overall bright rufous coloration (vs dark heavily streaked, or nearly solid dark brown brown and yellow-ocher). Unlike all flying in N. s. obscura of the Andamans. The nom- stages of N. ochruceu, it lacks facial pattem- inate race of the Andaman Hawk-Owl (N. a. ing, including the whitish supercilia typical of ufJinis> is smaller than N. scutulutu, to which most of its relatives, and also lacks white it is otherwise quite similar, while the larger markings in the wing coverts and flight feath- Nicobar race (N. a. isolutu) is even more like ers. Less obvious distinctions from N. ochru- some races of N. scutulata. ceu include its more triangular (vs squarer The highly varied subspecies (including a tipped) whitish scapular spots, its mainly ru- new one described from Roti Island, south- fescent rictal bristles (vs blackish with white west of Timor, Lesser Sundas; Johnstone and bases), its more narrowly barred rectrices, its Dame11 1997) usually grouped in the Southern vaguely dark-scalloped lower underparts (vs Boobook (Ninox novaeseelundiue) as well as plain ocher or somewhat brown-streaked), and the Manus Hawk-Owl (N. meeki) are also Rasmussen l A NEW SPECIES OF HAWK-OWL 461 120 - .:: “squamipila” ( 19) ,.:/ ’ . ’ ,/ -110- /.... ’ aa 2100 - zil 3 90 ‘ 9 k 80- 70- (70) I I &hen from sLU (mm) 10 *uricZar length3~mm) ,,,,..,......-: ,,......“ ”‘ 1 :f,,..,.....