Pygathrix nemaeus, (Linnaeus 1771) (Linnaeus, 1771)

Brandon-Jones, Douglas, 2024, The scientific discovery and subsequent history of the douc monkey Pygathrix nemaeus (Linnaeus, 1771) near Da Nang, Vietnam, Mammalia (Warsaw, Poland) 88 (4), pp. 353-361 : 357-358

5 Douc specimens collected near Da Nang

I. Geoffroy Saint-Hilaire (1851: 12) recorded that in 1837, near Tourane on the Bonite expedition, Eydoux and Souleyet collected a male foetus with the triangular patch at its tail base already evident. Eydoux and Souleyet (1841: xiv) were at Tourane from 25 January to 4 February 1837, but said nothing of the douc. Perhaps this was the youngster collected on the Favorite expedition. Probably similarly confused, Anderson (1879: 41) claimed, without corroboration, that: “ The naturalists of the ‘Bonite’ encountered it in numerous troops near Tourane ”.

I. Geoffroy Saint-Hilaire (1851: 12) also recorded an immature female from “ Cochinchine ”, collected on the Danaïde expedition and donated to the Muséum National d ’ Histoire Naturelle, Paris, in 1843 by (Naval Officer, Lieutenant Jean-Louis-Charles) Jaurès (1808 – 1870). Regrettably, this important expedition is largely unpublished.

Between 5 and 12 June 1897 on the (Son-Cha = Son Tra, see below) peninsula where sighting doucs was easy, Barthélemy (1901: 342) obtained two live ones. They were gentle and shy. He believed the species, thought endemic to Tourane bay, too delicate for previous live transport to France. Barthélemy ’ s (1898: 9) died in July 1897 after a fortnight at the Jardin des Plantes, Paris. Captive ones settlers kept in Tourane soon died, generally by selfstarvation, self-strangulation or, as Barthélemy ’ s (1898) magnificent large male did in its cage, by stunning themselves. (A possible cause is mineral deficiency decalcifying the cranial bones, making the brain more vulnerable to impact, see Brandon-Jones and Goudsmit [2022: 338 – 342].) Barthélemy ’ s (1901) consolation was that (Alphonse) Milne-Edwards subjected them to interesting studies. Their natural diet was lentisk berries and other mountain plants; they liked bananas, and for much of the voyage Barthélemy (1898) accustomed them to bread. Their copious water consumption led him to blame thirst for their melancholy, which otherwise implied reasoning capacity. Captivity seemed to affect their temperament, however, and next year he hoped to observe them in the wild.

Jean Delacour and Willoughby P. Lowe collected an adult female douc ZD.1926.10.4.5 (“ Iris brown. Face pale terra-cotta. Cheeks white. Hands black. Thighs black. Between thighs white. ”) on 20 November 1925, and an adult male ZD.1926.10.4.4 (“ Iris light brown. Face pale reddish. Chin cream. Hands black. Sexular [sic] region white. ”) on 3 February 1926 at Col des Nuages, 1200 ft (400 m) ( Napier 1985: 86; Thomas 1927: 43), the more recent name for Taysons pass (now Deo Hai Van, 16°12 ′ N 108°08 ′ E). On 7 February 1926 they also collected there ZD.1926.10.4.7, an adult female M. arctoides ( Fooden 1996: 878) . Thomas (1927: 42) misled Kirkpatrick (1998: 340) into duplicating this locality, creating a doppelgänger in Laos. A juvenile female USNM.269800 collected in January 1940 at Col des Nuages by J(oseph) F. Rock was the last douc recorded there until about 70 were discovered in about 3300 ha of forest on 10 November 2016. The opening of a road tunnel under the pass in 2005 may have alleviated the impact of road traffic ( Anon 2016). Lowe (1947: 28) described the locality thus:

The road was steep and wound round sharp curves as we ascended the mountain. At times we caught a glimpse of the breakers dashing against the rocks beneath.The further we went the thicker the forest became. We presently arrived at a small bungalow, at 1,200 ft., which we decided to make our headquarters for several days … It was a very wet locality, as its name implies. Rain and fog are of daily occurrence. Here was a favoured spot for rare and beautiful birds. Many occurred that had never been seen in the wild state by a white man; such as the Imperial Pheasant which lives in the densely-forested and leech-infested mountains … Then again there is a large shy and elusive Cuckoo [(Footnote) Carpococcyx renauldi ] living in the thickets and vine-covered retreats, where it is impossible to follow, much less to see it … We were especially anxious to find the handsome yellow-handed [(Footnote) Callosciurus flavimanus ] species, first mentioned in 1832 and since then unknown … we secured a series of [this squirrel] for the British and Paris Museums …

As with macaques, Van Peenen et al. (1971: 134) infrequently saw roadside doucs on Mt. Sontra (16°07 ′ N 108°18 ′ E), the mountain complex on the peninsula forming the eastern rim of Tourane Bay, but from 1965 to 1967 they were often seen in the lower branches of roadside trees at elevations from 200 m to the top of Peak 647 (the peaks were denoted by their altitudes in metres). From a tree about 60 m away, a troop of three doucs quietly watched traps being set in a rubbish dump near Peak 647 in September 1967, and in the late afternoon individuals were commonly seen eating leaves or grooming themselves. When disturbed, large males sometimes demonstratively brachiated to and fro. Doucs were observed in all forested parts of the peninsula, including rainforest, but were seen on the ground only momentarily when fleeing. As an endangered species, none were collected, but Van Peenen et al. (1971: 135) skinned seven confiscated from poachers or inadvertently shot by sentries. Relatively undisturbed rainforest occurred on the northern slopes between 300 and 650 m, with trees of 40 m and above, and a second canopy of young trees. Climbing vines and epiphytes were common, but the sparse undergrowth made the forest accessible, often with 10 m visibility. Where felling had occurred, most trees, neither predominantly deciduous nor broadleaf evergreen, attained 15 m, with occasional taller ones and deep, dense, impenetrable undergrowth of vines, shrubs, thorny palms and bamboo-like clusters. Dry forest was extensive at lower elevations, especially on the south side, primarily of woody vines and dense, low shrubs, but short, often gnarled and twisted trees were common ( Van Peenen et al. 1971: 130).

The seven douc specimens are an adult male USNM.356576 and a juvenile female USNM.356575 J. T. Lowery collected on 12 February 1966 ; an adult male USNM.356577 and an adult female USNM.356574 T. J. McIntyre and P. F. Ryan, respectively, collected on 13 February 1966 ; an adult male USNM.357628 D. Van Peenen collected on 12 March 1969; and two males USNM.357766-7 without skulls, but adult body size, R. H. Light collected on 29 April 1969 . Only the first four specimens have field measurements, and the locality of USNM.357628 is given as “ 2 km E & 8 km. N of Mt. Sontra Peak ”; that of USNM.357766 “ 3. 5 km E & 1. 5 km. N of Mt. Sontra ”. The National Museum of Natural History, Smithsonian Institution, Washington, D.C., also has two specimens with locality: “ Presequ ’ ile [sic] de Tien Sha , Danang ”. The first is an adult male USNM.358107 D. H. Manley collected in spring 1967; the second a subadult female USNM.356854 G. S. Jones collected in July 1967 . Tien Sha (now Tien Sa) is an earlier name for the Son Tra Peninsula. Its short (about 10 km) distance from Da Nang makes it the best candidate as type locality for P. nemaeus , should further restriction be desirable. Fooden (1996: 889) added an adult female skull FCXM 002 collected on 21 May 1984 , and a female unnumbered skin collected in November 1989, both preserved at the Forestry College of Vietnam, Xuan Mai. The dark grey shank of the skin ( Fooden 1996: 865) accords with Pygathrix cinerea Nadler, 1997 , indicating mistaken provenance.