Mammals of Papua

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Dedicated to biological, distributional, historical and taxonomic aspects of mammals throughout the Papuan region

Grizzled Tree-kangaroo Dendrolagus inustus Müller, 1840

- Müller, S. (1840): Type locality: Mt. Lamantsjieri, Fakfak Div., Lobo district, near Triton Bay, West Papua (= Irian Jaya), Indonesia (Husson, 1955; Groves, 1982, 2005).

  • Other common names: Finsch's Tree-kangaroo (D. i. finschi). French: Dendrolague Gris. Spanish: Canguro Arborícola Gris.
  • Local names: Wakera (Lobo Bay area, Papua Province), Yonqui (Sandaun Province, PNG).
  • Synonyms: Dendrolagus maximus (Rothschild and Rothschild, 1898), Dendrolagus keiensis (Matschie, 1916b), Dendrolagus schoedei (Matschie, 1916b), Dendrolagus sorongensis (Matschie, 1916b).
  • Etymology: Genus - ? Species - dusky, or imprint, crimp or curl (L.) a reference to the pelage (Flannery, 1995b).
  • Holotype: D. i. inustus: sub-adult female (RMNH 13483. Skin and skull) collected by ?; D. i. finschi: unsexed adult (ZMB45, tail) collected by ? (Groves, 1982).

Type locality: D. i. finschi (Matschie, 1916): Tami River, 5km east of the border between Papua Province and PNG, North Coastal Range, Sandaun (West Sepik Province), PNG (Matschie, 1916; Groves, 1982).

- Taxonomic history: This species was described by Müller (1840) based on a sub-adult female (RMNH 13483) collected at Mt. Lamantsjieri in “German New Guinea” (Western New Guinea); being only the second Dendrolagus species to be scientifically described. The Genus Dendrolagus was described by Schlegel and Müller (1841), with D. ursinus and D. inustus being ascribed to it. Müller & Macklot (1828) and Jentink (1879) cited the type locality for D. i. inustus as the Lobo Bay (West Papua, Indonesia) but it was later corrected to Mt. Lamantsjieri, near Lobo, Triton Bay by Husson (1955). The Museum für Naturkunde (ZMB; Berlin, Germany) received a exceptionally large collection of Dendrolagus specimens in the late 19th and early 20th based on which Paul Matschie (curator of mammals at ZMB by the time) described D. keiensis, schoedei and sorongensis (Matschie, 1916b) all of which are now treated as synonyms of D. inustus; also described D. finschi as a distinct species, based on an unsexed tail skin (

The Genus was reviewed by Rothschild & Dollman (1936) who concluded that finschi is best treated as a subspecies of Dendrolagus inustus, an taxonomic position which since has been widely followed (Groves, 1982; Flannery, 1990a; 1995ab, 1996; Groves, 2005; Martin, 2005; Helgen, 2007ab; Leary in litt 2008).  

Tate (1948) concluded that the holotype of D. keiensis did not originate from Kai Besar (= Great Kai Island) but that it was obtained from a dealer on the Vogelkop Peninsula. 

The Genus was revised again by Tate (1948) who chose to place D. inustus in what he called the "D. ursinus-group", this revision seems to have been based on very few actual specimens and he went on to strongly argue that D. ursinus and D. inustus was actually colour phases of the same species, both having been collected from the same type locality (Groves, 1982). Unfortunately the revision by Tate (1948) seems to have been given priority over Rothschild and Dollman (1936) by some later authors, including Lidicker and Ziegler (1968) which treated D. inustus as a synonym of D. ursinus. Kirsch and Calaby (1978) chose to follow Rothschild and Dollman (1936). Groves (1982) comprehensively reviewed the Genus and which clearly showed that D. ursinus and D. inustus should be treated as two separate species.

- Characteristics and identification: The Dendrolagus inustus can be distinguished from all other New Guinea Dendrolagus. by its longer hind-foot (140-160 versus 90-135mm), this species belong to a primitive group (together with D. lumholtzi and D. bennettianus), being less arboreal adapted in hind-limb morphology; the grizzled coloration with a distinct black ear on a grey head and large callosity at the base of tail on the dorsal side. Full-grown individuals of D. i. inustus reach a very large size, and males are almost twice as large as females; with one captive male held in the Gladys Porter Zoo (USA) weighed 23,18kg, by far the heaviest tree-kangaroo ever recorded, with the possibility that this specific individual was obese. Bones of wild caught specimens suggest that D. i. inustus sometimes reach an enormous size; D. i. finschi is the second largest Dendrolagus, with adult males reaching 17 kilograms in the wild (heaviest Dendrolagus ever recorded in the wild) but males average 15.5 kilograms, while females average 11.4 kilograms (Flannery, 1995ab, 1996). Compared with most other New Guinea tree-kangaroos, the Grizzled Tree-kangaroo is a rather rangy animal, with long limbs and a small head. In this regard it somewhat resembles in shape the terrestrial kangaroos. The males, in particular, show massive development of the forearms. From a distance, its overall colour appears to be grey, although some individuals have a rusty tinge.

The tail is very long, grey and often thickly furred. Occasionally, bands of lighter and darker grey can be discerned, giving it a ringed appearance. It has very large ears for a tree-kangaroo, and when it is sitting in a tree, they characteristically point sideways from the head rather that upwards as in most kangaroos. This doubtless tends to focus the animal's hearing towards the forest below, the direction from which danger is most likely to come. Most tree-kangaroos tend to do this, but because the ears are so large it is particularly noticeable in this species (Flannery, 1995ab, 1996).

(D. i. finschi. Keroom District, Papua Province)

Distinctiveness of the two subspecies recognized rests on rather slim grounds, as museum specimens are few and little detailed study has been done on this species and they are indeed very similar. Probably more closely similar than any other Dendrolagus species; D. i. inustus: the most important difference discerned so far concerns the colour of the face; the forehead is grey or brownish in the nominate subspecies, the colour of the limbs and tail is similar to that of the body (more contrasting in D. i. finschi); D. d. finschi: the darker forehead is probably the most reliable distinguishing feature (Flannery, 1995ab, 1996). The few specimens from Yapen Island has been described by Groves (1982) as being different from individuals elsewhere in throughout the distribution, he mention them as having a red-brown cast, though not as much as is usual in D. i. finschi, and that this tone extends to the cheeks and underparts unlike other specimens of either race.

- Geographic Range: Endemic to the Papuan region this species is widespread throughout western and northern mainland New Guinea, with two distinctive subspecies currently recognized (Rothschild & Dollman, 1936; Groves, 1982, 2005; Flannery 1990, 1995ab, 1996; Martin, 2005; Helgen, 2007ab; Leary in litt. 2008). It remains unknown whatever the distributions of the two races are in contact, but present evidence indicates not (Groves, 1982).

1.) D. inustus inustus (Müller, 1840).

Identification:

Distribution: NE Vogelkop Peninsula eastwards throughout the Bird's Head region (including the Fakfak and Kumawa Mts, Fakfak Peninsula), extending as far eastward as the western shores of Etna Bay, Papua Province, Indonesia; Mt Eiori, Yapen Island (Cenderawasih Bay, Papua Province). Very few specimens has been collected from Yapen and the taxonomic position of this population remains unknown, Groves (1982) provisionally included this population in the nominate race, a position we choose to follow after consulting relevant literature. Flannery (1995a) mentioned the probable occurrence of this species on northern Salawati I. in the Raja Ampat Archipelago off the Birds Head (formerly Vogelkop) Peninsula where he, based in interviews with local people obtained descriptions of a mammal matching this species, but as yet no specimens has been obtained. Groves (1982) examined a specimen purportedly collected from Waigeo (Raja Ampat, West Papua), a locality that he considered to be dubious. It has been erroneously reported from Kai Besar (= Great Kai Island) in the Kai Islands (Matschie, 1916b; Rothschild & Dollman, 1936; Tate, 1948; Flannery, 1995b) as well as the Aru Islands (Rothschild and Dollman, 1936; Groves, 1982; Flannery, 1995b). T. Leary in litt. (2008) included Misool and possibly Batanta (Raja Ampat, West Papua) in the range description of the species, the  basis of this remains unknown to us. 

  • 2.) D. inustus finschi (Matschie, 1916b): restricted to the North Coastal Ranges, with documented records from the Bodem River (south of Siduari Mts, Mamberamo Basin) eastwards throughout the lower reaches of the Van Rees, Foja, Cyclops, Bewani and Torricelli Mts, extending eastward to Wewak in the East Sepik Province (Groves, 1982; Flannery, 1995a, 1996; D. Spiggs pers. comm). It is restricted to the northern slopes of the North Coastal Ranges, except adjacent to the Papua Province border, where it extends inland as far as Amanab (Sandaun Province, PNG). The absence from many apparently suitable areas on the southern slopes of the North Coast Ranges remains unexplained (Flannery, 1996).

- Natural History, Habitat and Ecology: The diet of D. inustus still remain poorly known but due to studies being undertaken on D. i. finschi in the Torricelli Mts (West Sepik Province, PNG) the knowledge concerning the diet of this species has greatly improved, and largely consist of Schuurmansia sp. (young leaves), Ficus sp. (leaves and fruits), Gnetum sp. (leaves), Tetracera sp. (leaves), Elatostema sp. (leaves) and Araceae sp. (leaves); Ganslosser (1981) mention that the diet of a captive individual largely consisted of meal-worms and boiled eggs.Another aspect that needs further studies is data relating to reproduction; females do not reach sexual maturity until they are about 10 kilograms in weight. Populations in the Torricelli Mts appears to be reproducing throughout the year; with a young being recorded in March weighing 200g, young recorded in March weighing 400-500g and young recorded in December weighing 600-700g. With one female captured in June had a newborn young in the pouch and was accompanied by a young at foot weighing 5kg. Twins has been recorded once in D. i. finschi and the twins weighed 400 grams each and were healthy when examined (Flannery, 1995a, 1996). Might have a higher metabolic rate -- and thus more rapid growth and higher reproductive rate than other New Guinea Dendrolagus species.

Table 1. The history of Grizzled Tree-kangaroo D. inustus in captivity

Tree-kangaroos have been kept in captivity by Europeans since the mid-nineteenth century. Some species are hardy and have survived for years in small cages, fed on such unusual diets as boiled rice, biscuits and sardines. London Zoo was the first zoological garden to exhibit a living tree-kangaroo. An female Grizzled Tree-kangaroo (Dendrolagus inustus inustus) was acquired on 8 October 1848, and died on 13 October 1852. It has been brought to London by Lieutenant-Colonel Butterworth C. B., governor of Singapore, although exactly how he acquired it remains unknown. This unfortunate animal had most of its tail amputated (Flannery et al. 1996). London Zoo acquired another individual on 4 November 1865 (Sclater, 1865), and yet another on 19 November 1877. Both were still alive in 1882 (Sclater, 1883). In 1890 the Adelaide Zoo acquired two individuals directly from New Guinea, they proved short-lived at Adelaide, one individual died in 1891 while the second individual died in 1894 (Rix, 1978).

Beginning in the 1950s up until the early 1980s the Grizzled Tree-kangaroo (D. inustus) was the most common tree-kangaroo species in captivity, with 105 wild-caught individuals taken into captivity in the years 1954-1984 according to the International Zoo Yearbook vols. 1-26 (Smith, 1988). Of these 52 went to North American collections, 21 of them reproduced but 6 out of 27 wild-caught females died within one year (Steenberg, ?). Beginning in the 1980s the captive population of Grizzled Tree-kangaroo in European and North American institutions experienced a steady decline in numbers.

According to the 1994 International Studbook for Tree-kangaroos no Grizzled Tree-kangaroos remained in European institutions, meanwhile the captive population in North America stood at to 1.6 individuals held at three institutions (Collins, 1995). But by this time the captive population in North America consisted of aging animals (the male was 11 years old and the females average age was 12.8 years) so Collins (1995) concluded that unless there would be additional recruitment of animals from the wild then the captive population in North American institutions would cease to exist.

  • Surabaya Zoo (Java, Indonesia): they kept several adult individuals in July 2006 (S. Hogberg visit July). On a more recent visit in December 2008 only a single adult was observed (I. Khunko visit December 2008).  The animals kept are in good condition and with decent climbing possibilities in their enclosure, which however is a bit on the small side. Some online sources incorrectly suggests that the tree-kangaroos kept at Surabaya (Zoo) is Ursine Tree-kangaroo D. ursinus (I. Khunko pers. comm). Subspecies: inustus
  • Taman Safari (Java, Indonesia): this species has been kept here since 1994. In 1994 an individual kept as a pet was donated by local people, which was followed by a pair (1.1) confiscated by Indonesian authorities in 1995. It was successfully bred for the first time in 1999, and then again in 2006. The female of the pair received in 1995 died in 2008. Some online sources incorrectly suggests that the tree-kangaroos kept at Surabaya (Zoo) is Ursine Tree-kangaroo D. ursinus (I. Khunko pers. comm). Subspecies: inustus
  • Bandung Zoo (Java, Indonesia): some online sources suggests that they keep an Lumholtz's tree-kangaroo D. lumholtzi at the side of the elephant house. Given the extreme rarity of this species even Australian zoos this seems highly unlikely. In reality the species kept is probably Grizzled tree-kangaroo which can appear similar, it is also not uncommon for animals to be mislabeled in Indonesian zoos (I. Khunko pers. comm).
  • Tenkile Conservation Alliance (Papua New Guinea): in mid-2008 they kept at least four individuals (2.2) at their base located at Lumi in the Torricelli Mts, the founding 1.2 confiscated from hunters. It has been successfully bred with a single male born in 2009. Subspecies: finschi
  • Adventure Park (Port Moresby, National Capital District, Papua New Guinea): they keep a decent-sized group of 7-8 adult individuals, including females with pouch young (Nick Hobgood pers. comm March 2013). Subspecies: finschi
  • Los Angeles Zoo (California, USA): 2.3 (1976); 1.1 (1979-1981). Subspecies: inustus
  • Santa Barbara Zoo (California, USA): 1.1 (?); 0.1 (1979). Subspecies: inustus
  • Albuquerque Biological Park (New Mexico, USA): 0.2 (1979). Subspecies: inustus
  • Phoenix Zoo (Arizona, USA) Subspecies: inustus
  • National Zoo (Washington, USA): 193? to 195? (D. i. inustus); 1939 to 1945 (D. i. finschi); but it was never bred. On 1 December 1936 they received an hybrid male (D. ursinus x D. inustus inustus) born at Philadelphia (Zoo), it died here on 13 July 1943 at an age of 7 years and 6 months (Weigl, 2005). The skin and skull of this male is now in the collections of the Smithsonian Institute (USNM 271183) (Flannery et al. 1996). Grizzled Tree-kangaroo (D. i. inustus): two individuals (0.0.2) held in June 1938-June 1939; three individuals (0.0.3) held in June 1941; two individuals (0.0.2) held in June 1944-June 1947; one individual (0.0.1) held in June 1948-June 1957. Finsch's Tree-kangaroo (Dendrolagus i. finschi): on 15 August 1939 they received three individuals (0.0.3); three individuals (0.0.3) held in June 1941-June 1945. One of the individuals received on 15 August 1939 died on 7 December 1945 at the age of 6 years and 3 months. This is reported as Longevity record for this subspecies in captivity (Weigl, 2005). Subspecies: inustus and finschi
  • Philadelphia Zoo (Pennsylvania, USA): 0.1 (1965-1966). The only tree-kangaroo hybrid (D. ursinus x D. inustus) ever recorded was born here. This male was born at Philadelphia (Zoo) on 23 December 1935, during an era in which zoo keepers tended to keep similar species in the same enclosure. One parent was a Grizzled Tree-kangaroo (D. inustus inustus) whilst the other was an Ursine Tree-kangaroo (D. ursinus) (Flannery et a. 1996). This hybrid was transferred to the National Zoo, Washington on 1 December 1936 (Weigl, 2005). Subspecies: inustus
  • Gladys Porter Zoo (Texas, USA): ? to 1997?; 0.1 (1994-1997). Female "Grinch" (studbook number 89) arrived from Oklahoma City Zoo on June 17th 1991 (born at San Antonio on 1st April 1978), still kept at Gladys Porter in late 1997 so presumably kept here up until her death. At one point they kept an adult male weighing 23,18kg, which is by far the heaviest Dendrolagus ever recorded (Flannery et al., 1996). Subspecies: inustus
  • Baton Rouge Zoo (Louisiana, USA): 0.2 (1981). Subspecies: inustus 
  • Jackson Zoological Park (Mississippi, USA): 0.2 (1981). Subspecies: inustus
  • North Carolina Zoo (North Carolina, USA): 2.1 (1979); 0.1 (1981). Subspecies: inustus
  • Oklahoma City Zoo (Oklahoma, USA): February 1974 to 17 June 1991, it was successfully bred multiple times; 5.13 (1976); 2.11 (1979); 1.5 (1981); 3.3 (1984-1985); 1.2 (1990); 0.1 (1991). In 1977 they kept a total of 15 individuals in three breeding groups, situated in two different parts of the zoo; females in all three breeding groups successfully bred with the dominant male in each group. The female "Mama Roo" which arrived at Oklahoma (City Zoo) in February 1974 (kept with 1 adult male, another adult female and a sub-adult female) gave birth to a joey on 7 February 1975, which was found dead on the floor in the enclosure. Another female "Lill Roo" gave birth to a joey in April 1975, the same female gave birth to a second joey on 6 July 1976 (Turner, 1977). Subspecies: inustus
  • The Female "Grinch" (studbook number 89) arrived from San Antonio Zoological Park (where it was born on 1st April 1978) on 26st February 1986 and left for Gladys Porter (Zoo) on 17th June 1991. 
  • San Antonio Zoological Garden (Texas, USA): 1.2.1 (1976); 1.3 (1979-1981); 2.8 (1985); 2.3 (1990); 0.2 (1994-1995); 0.1 (1996-1997); the Female "Grinch" (Studbook number 89) was born on 1st April 1978 to female (Studbook number 72) and male (Studbook number 82); transferred to Oklahoma City Zoo on 26st February 1986. Another female "Kate" (Studbook number 116) was born on 28th July 1983 to female (Studbook number 48) and male (Studbook number 82), and she was still kept at San Antonio as of December 1994. Received female "Peg" (Studbook number 98) from Winnipeg (where it was born) on 17th September 1987 and where it still remained as of December 1994. On 13th May 1992 they received the females "Georgina" & "Jaqueline" (Studbook number 97 & 113) born at Krefeld Zoo (Germany) on 1st October 1979, respectively 1st August 1982. Both were transferred to Jacksonville Zoo on 14th May 1993.  Some of the individuals kept at this institution were on breeding loan from New Orleans. This was the last institution in North America to keep this species, the last Grizzled Tree-kangaroo at San Antonio died in May 2006, at 17 years old (Steenberg ?). Subspecies: inustus 
  • New Orleans Zoo (Louisiana, USA): ? to 1992; 3.4 (1976); 1.4 (1979); 0.1 (1990); Female "Becky (studbook number 131) was born on 2nd July 1986 to female (studbook number 48) and male (studbook number 82); she was transferred to Jacksonville Zoo on 9th March 1992.  Subspecies: inustus
  • Jacksonville Zoo (Florida, USA): 1.2 (1976); 1.1 (1981); 1.4 (1985); 1.1 (1990); 1.3 (1994-1996); 1.2 (1997); Male "Newton" (studbook number 115) was born on 18th June 1983 to female (studbook number 62) and male (studbook number 91) and still remained at Jacksonville as of December 1994. On 9th March 1992 they received an female "Becky" (studbook number 131); born at New Orleans (Zoo) on 2th July 1986.  On 14th May 1992 they received 0,2 "Georgina & Jaqueline" (studbook number 97 & 113), born at Krefeld Zoo (Germany), from San Antonio where they still remained as of December 1994. Georgina & Jaqueline" (studbook number 97 & 113) were on breeding loan from San Antonio. Subspecies: inustus
  • Toronto Zoo (Ontario, Canada): 0.2 (1976); 0.3 (1979); 0.2 (1981); 1.1 (1985). Subspecies: inustus
  • Winnipeg Zoo (Manitoba, Canada): 197? to 1987; 1.2 (1976); 1.1 (1979); 1.2 (1980-1981); 0.2 (1985); 0.1 (1987). Female "Peg" (studbook number 98) was born on 10th October 1979 to female (unknown studbook number) and male (studbook number 63) kept at Winnipeg. The female born in October 1979 was the last individual kept in this institution; transferred to San Antonio (Zoo) on 17th September 1987. Subspecies: inustus 
  • Tierpark Berlin (Germany): 1975 to 1989; 0.1 (1970); 1.1 (1976); 2.1 (1979); 3.1 (1981); 1.1 (1985); 0.1 (1986). It was successful bred for the first time in 1977 (Petzold, 1978; Blaszkiewitz, 1988; Kern, 2010).
  • Berlin Zoological Garden (Germany): 1985 to 1990. 1.1 (1976); 1.2 (1979-1981); 0.1 (1985). It was successful bred for the first time in 1977 (Klös, 1969; Klös & Klös, 1994).
  • Duisberg Zoo (Germany): 1974 to 198?; 1.2 (1976); 1.0 (1981); successfully breed in 1976, which was the first successful breeding in a German zoo. As they arrived at Duisberg (Zoo) they were erroneously designated as D. ursinus, but they were later correctly identified as D. inustus.  
  • Krefeld Zoo (Germany): 1975 to May 1992; 1.1 (1976); 1.3 (1979); 1.4 (1981); 2.2 (1985); regularly breed. The female "Georgina (studbook number 97) was born on 1st October 1979 to female (studbook number 56) and male (83) while the female "Jaqueline" (studbook number 97 & 113) was born on 1st August 1982 to female (studbook number 97) and male (studbook number unknown); both these females were transferred to San Antonio (Zoo) in May 1992. They were the last remaining D. inustus kept in Europe and were moved to the USA to be paired with males remaining there (?). Subspecies: inustus. 
  • Darmstadt Zoo (Germany): 0.1 (1976).
  • Bremerhaven Zoo (Germany): 1.1 (1979).
  • Frankfurt Zoo (Germany): 1962 to 1963, they never bred (Scherpner, 2011).
  • Hannover Zoo (Germany): 1973 to 1975, they never bred. They were apparently labeled as D. ursinus while kept at the zoo; however, the true identity of the Dendrolagus species kept here remains unknown. The taxonomy of Dendrolagus kangaroos kept in Europe at this time remains rather confusing and there is good examples of other Dendrolagus being labeled as D. ursinus around the same time, which later turned out to later correctly identified as D. inustus only later (see under Duisberg Zoo).
  • Köln Zoo (Germany): 1965 to 197?; 1.0 (1965-1970); never bred (Pagel, 2011).
  • Neuwied Zoo (Germany): kept in 1976/77.
  • Osnabrück Zoo (Germany): 1.1 (1979); never bred.
  • Amsterdam Zoo (The Netherlands): 0.3 (1960); 0.2 (1965); 1.1 (1976); 2.1 (1979); 1.1 (1981).
  • Rotterdam Zoo (The Netherlands): 0.1 (1965-1966); 1.1 (1976-1979).
  • London Zoo (England, UK): 1848 to 1852; 1865 to ?; 0.1 (1970); never bred. A female Grizzled Tree-kangaroo (Dendrolagus inustus inustus) was acquired on 8 October 1848, and died on 13 October 1852. It has been brought to London by Lieutenant-Colonel Butterworth C. B., governor of Singapore, although how he esquired it remains unknown. The unfortunate animal had most of its tail amputated (Flannery et al. 1996). On 4 November 1865 they received an individual in exchange, while on 19 November 1877 they purchased a second individual (Sclater, 1883). Both were still alive in 1882 (Sclater, 1883).
  • Bristol Zoo (England, UK): 1.1 (1979); 0.1 (1981).
  • Dublin Zoo (Ireland): 1.0 (1960-1961).
  • Napoli Zoo (Italy): 0.2 (1976); 0.1 (1981).
  • Asahiyama Zoo (Japan): 1.1 (1976); 0.1 (1979).
  • Singapore Zoo (Singapore): 3.3.1 (1979); 4.3 (1981); 3.2 (1985); 2.1 (1990).
  • Ragunan Zoo (Indonesia): 1.2 (1979).
  • The Rainforest habitat (Papua New Guinea): 1.1 (199?-2007).
  • Baiyer River Sanctuary (Papua New Guinea): 1.1 (1976).
  • Taronga Zoo (Australia): specimens kept here has been donated to the Australian Museum (Sydney, New South Wales). Presumably donated to the zoo by Edward Hallstrom.
  • Adelaide Zoo (Australia): 1890 to 1894, but it was never bred. Two specimens were obtained from New Guinea in 1890, and both specimens were in the 1891 animal inventory. The 1892 animal inventory contained only one specimen, this was shown again in the inventory for 1893 and 1894, but in 1895 it too was missing (Rix, 1978).
  • Melbourne Zoo (Australia): 1.0 (1966-1970).

- Conservation Status: Vulnerable (2008 IUCN Red List). This species is being over-exploited throughout much of its distribution due to growing human population pressure, it still remains common in remote and sparsely populated areas but the number do continue to decline in most areas where it still survives (Flannery, 1995ab, 1996). Individuals caught in the heavily hunted Mount Somoro (Torricelli Mts) are smaller than those from less densely populated areas and it is probable that hunting is so intense in the Mount Somoro area that the wide majority of animals are killed before they reach maximum size. In the Torricelli Mts this species is usually hunted with dogs, but occasionally hunters is able to catch animals resting in the canopies in trees unaided. Males are often reported to live solitary and they only rarely associate with females in order to avoid capture, hence they sometimes grows to large sizes (Flannery, 1995ab, 1996). It might occur at higher densities in the absence of humans and the population in the northern coastal range of New Guinea is considerably more threatened than other populations and this species is not only threatened by hunting but also due to habitat loss and degradation through conversion of forest to small-scale agricultural use, and large-scale oil palm plantations (Leary et. al 2008). This species was listed as Vulnerable by Flannery (1995a), as Data Deficient by Baillie and Groombridge (1996) while Leary in litt (2008) chose to list it as as Vulnerable.

Jentink (1879) summarized the known specimens of D. i. inustus held at RMNH (Leiden, The Netherlands) which is as follows: specimens was secured by van Rosenberg at Andai (Vogelkop), by Hoedt at Dorei (Vogelkop), by Diard from the Arfak Mts (Vogelkop), by Wallace from north-west New Guinea (Vogelkop) meanwhile Beccari and Albertis secured specimens from Sorong respectively Dorei (Vogelkop).