Columba torringtoni SRI LANKA WOOD-PIGEON. Critical Endangered Vulnerable B1+2a,b,c,d,e; C1

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1 SRI LANKA WOOD-PIGEON Critical Endangered Vulnerable B1+2a,b,c,d,e; C1 This pigeon has a small, declining population and range, which is also severely fragmented, as a result of the destruction of hill and montane forest. It therefore qualifies as Vulnerable. DISTRIBUTION The Sri Lanka Wood-pigeon is endemic to Sri Lanka, where it is mainly confined to the montane forests (above c.1,000 m) of the hill zone in the mountains of the centre of the island, although it regularly moves to lower altitudes. Its forest habitat is now fragmented within its small range (see Threats). Records (arranged approximately from north to south) are as follows: SRI LANKA Gammaduwa, 900 m, one, August 1938 (Whistler 1944); Corbett s Gap, Knuckles range, two, (IUCN/WCMC 1997), two, February 1996 (Ceylon Bird Club News February 1996); Midlands Estate, 1,200 m, pair, March 1997 (Ceylon Bird Club News March 1997); Mahiyangana, undated (Ceylon Bird Club News November 1975); forest above Kandy, before 1876 (specimen in BMNH), pair heard, February 1989 (Ceylon Bird Club News February 1989), one, December 1990 (Ceylon Bird Club News December 1990), heard regularly and a pair seen at Sancta Maria-Kandy (Ceylon Bird Club News October 1988), at Gannoruwa, December 1996 (Ceylon Bird Club News December 1996), at Rosnith hill, undated (Ceylon Bird Club News September 1993) and November 1997 (Ceylon Bird Club News November 1997); Udawattakele sanctuary, undated (Ceylon Bird Club News May 1976); Peradeniya botanical gardens, September 1993 (Ceylon Bird Club News September 1993); Gampola, undated (Legge 1880); Loolecondera Estate, Deltota, October 1980 (Ceylon Bird Club News 1980); Cocoawatte estate, Lunugala, c.1895 (Butler 1896, female in BMNH); Kitulgala, undated (Ceylon Bird Club News January 1988); Uda Pussellawa, nesting, November 1894 (Butler 1896); Uva basin, frequently recorded, December 1992 (Ceylon Bird Club News December 1992); Galways Land Sanctuary, September 1973 (Ceylon Bird Club News September 1973), four, January February 1977 (R. L. Fleming Jr. 1977), regularly seen (Ceylon Bird Club News 1981), one, March 1985 (Denholm and Denholm 1985), April 1986 (Ceylon Bird Club News April 1986); Nuwara Eliya, 1871 (specimen in AMNH), many records until at least 1998 (Ceylon Bird Club News, many observers in litt.); Moon plains, May 1918 (female in NMGC); Kandapola Sitaeliya Forest Reserve, undated (Ceylon Bird Club News September 1981, March 1982), two, (IUCN/WCMC 1997); Nanuoya, pair shot in heavy forest on fruit tree, June 1961 (two specimens in FMNH); Namunukula, three, (IUCN/WCMC 1997); Hakgala, April 1923 (several specimens in BNHS, NMGC), many records until at least January 1998 (Ceylon Bird Club News, many observers in litt.), and in the Botanical Gardens, undated (Ceylon Bird Club News December 1983, December 1986), one, February 1993 (T. Carlberg in litt. 1999); Meepilimana, one, (IUCN/WCMC 1997); Conical hill, one, (IUCN/ WCMC 1997); Bomuraella Oya-Parawella Falls, undated (Ceylon Bird Club News April 1991); Welimada (Wallalode), 450 m, October 1923 (Ripley 1946, two specimens in BMNH), February 1987 (Ceylon Bird Club News February 1987), undated (Ceylon Bird Club News December 1992), February 1993 (Ceylon Bird Club News February 1993), at Benhead Estate, undated (Ceylon Bird Club News February 1987), at Surrey Tea Estate, four in January February 1977 (Fleming 1977), two in January 1988 (Ceylon Bird Club News January 1988) and undated (Ceylon Bird Club News October 1981, December 1984, December 1986, February 1993), at 1531

2 Threatened birds of Asia SRI LANKA I N D I A N O C E A N 1532

3 50 Acre Estate, Surrey, undated (Ceylon Bird Club News January 1988), and 1 2 regularly down to the present (D. Warakagoda verbally 2000); Dickoya, undated (Ceylon Bird Club News January 1974); Hapugastenna, five, January February 1977 (Fleming 1977), December 1992 (Ceylon Bird Club News December 1992); Fitzroy Park-Ambewela farm, February 1983 (Ceylon Bird Club News February 1983); Mirahawatta, undated (Ceylon Bird Club News February 1987); Pattipola, two at the reservoir, December 1997 (Green and Dunbar 1997), two at Pattipole-Ambawala, (IUCN/WCMC 1997); Bandarawela, nesting in a wooded garden, April 1988 (Ceylon Bird Club News April 1988); Aniyakanda Estate, Kabillawela South, undated (Ceylon Bird Club News October 1987), nesting pair, 1988 (Ceylon Bird Club News April 1988); Thotupolakanda (Totupalakande), undated (Ceylon Bird Club News August 1987); Adams Peak, undated (Legge 1880); Ohiya, 1,750 m, November 1936 (Whistler 1944, juvenile male in BMNH), one, (IUCN/WCMC 1997); Horton Plains, undated (Legge 1880), two, (IUCN/WCMC 1997), many records until at least 1997 (Ranawana and Bambaradeniya 1998); Agra Bopats, two, (IUCN/WCMC 1997), undated (Ceylon Bird Club News September 1997); Bogawantalawa, undated (Ceylon Bird Club News September 1997); Carney-Adams Peak, undated (Ceylon Bird Club News January 1981); Haputale Rally Farm, Idalgashinna, undated (Ceylon Bird Club News December 1992); Palabaddala, August 1876 (male in BMNH); Tangamalai Sanctuary, Haputale, January 1981 (Ceylon Bird Club News January 1981), February 1990 (Ceylon Bird Club News February 1990), February 1992 (Ceylon Bird Club News February 1992), April 1992 (Ceylon Bird Club News April 1992), four, February 1993 (Ceylon Bird Club News February 1993), three, (IUCN/WCMC 1997); Haldummulla, undated (Ceylon Bird Club News November 1975); Peak Wilderness Sanctuary, one, (IUCN/WCMC 1997), May October 1997 (Ranawana and Bambaradeniya 1998); Mungastenna-Samanalawewa, including Samanalawewa hydroelectric project area, October November 1988 (Ceylon Bird Club News November 1988); Ratnapura, March 1874 (two specimens in BMNH), July 1895 (male in AMNH); Balangoda, October 1923 (male in NMGC); Morapitiya, recently (Ceylon Bird Club News June 2000); Delwala forest, m, several birds, July September 1997 (Jones et al. 1998), frequently seen, (K. Weerakoon in litt. 2000); Kudumiriya forest, m, six sightings, July September 1997 (Jones et al. 1998); Walankanda Forest Reserve, 400 1,100 m, nine sightings, July September 1997 (Jones et al. 1998); Yagirala, Kalutara district, four at Hawana University Forest Reserve, November 1990 (Ceylon Bird Club News November 1990), one, (IUCN/WCMC 1997); Timbulketiya, March 1934 (male in NMGC); Sinharaja Forest Reserve, undated (IUCN 1990), many records until at least January 1995 (R. Skeen in litt. 1999); Dellawa, one, (IUCN/WCMC 1997); Pitarathmale (untraced), February 1987 (Ceylon Bird Club News February 1987); Malhaygama (Merthaygama) (untraced), December 1866 (two specimens in BMNH). POPULATION It is difficult to estimate the population size and trends of this species, because it undertakes movements in search of fruiting trees, and its apparent abundance at particular The distribution of Sri Lanka Wood-pigeon (map opposite): (1) Gammaduwa; (2) Knuckles; (3) Midlands Estate; (4) Mahiyangana; (5) Kandy; (6) Udawattakele; (7) Peradeniya; (8) Gampola; (9) Deltota; (10) Cocoawatte; (11) Kitulgala; (12) Uda Pussellawa; (13) Uva basin; (14) Galways Land Sanctuary; (15) Nuwara Eliya; (16) Moon Plains; (17) Kandapola Sitaeliya Forest Reserve; (18) Nanuoya; (19) Namunukula; (20) Hakgala; (21) Meepilimana; (22) Conical Hill; (23) Bomuraella Oya; (24) Welimada; (25) Dickoya; (26) Hapugastenna; (27) Ambewela; (28) Mirahawatta; (29) Pattipola; (30) Bandarawela; (31) Kabillewela; (32) Thotupolakanda; (33) Adams Peak; (34) Ohiya; (35) Horton Plains; (36) Agra-Bopats; (37) Bogawantalawa; (38) Carney; (39) Haputale; (40) Palabaddala; (41) Tangamalai Sanctuary; (42) Haldummulla; (43) Peak Wilderness Sanctuary; (44) Mungastenna; (45) Ratnapura; (46) Balangoda; (47) Morapitiya; (48) Delwala; (49) Kudumiriya; (50) Walankanda Forest Reserve; (51) Yagirala; (52) Timbulketiya; (53) Sinharaja Forest Reserve; (54) Dellawa. Historical (pre-1950) Fairly recent ( ) Recent (1980 present) Undated 1533

4 Threatened birds of Asia sites can rapidly change (see Jones et al. 1998). In the late nineteenth century it was described as numerous above 900 m and plentiful at Horton Plains, the Peak Forests and Nuwara Eliya plateau forests, but below about 900 m it was not numerous (Legge 1880). It was still considered plentiful in the highland forests in the mid-twentieth century (Phillips 1978), but then to have declined because of habitat loss (Hoffmann 1984, see Threats). It was recently described as rare (Kotagama and Fernando 1994), and uncommon even within its stronghold in the central mountains (D. Warakagoda in litt. 1999). During a major survey of over 200 forest sites in Sri Lanka in , this species was recorded in only 13 of them (IUCN/WCMC 1997). Given its small range and the reduction in the area of its forest habitat, it is unlikely that it currently numbers more than a few thousand individuals. ECOLOGY Habitat This species is mainly found in montane forest above c.900 m, where it can usually be seen in lofty trees in the primeval forests of the mountains (Legge 1880), but it sometimes descends as low as 300 m in the lowland forests of the wet zone (Henry 1955, Phillips 1978). It is strictly arboreal, and is usually found in pairs in the canopy of tall trees or at the forest edge, although it will gather in small flocks when food is abundant (Henry 1955, Fleming 1977). It feeds in fruiting trees in the forest; for example its numbers increased at Delwara forest when bombu Symplocos cochinchinensis trees came into fruit (Jones et al. 1998). It has been observed feeding on fruiting trees such as jak in village gardens (Henry 1955), and it is regularly seen in upland tea estates (G. de Silva Wijeyeratne in litt. 2000) and in well-wooded homegardens in the Welimada, Bandarawela and Haldummulla areas, where it may occasionally breed (D. Warakagoda verbally 1999). It visits lowland forests to feed on certain fruiting trees (Kotagama and Fernando 1994), but a bird was recently found sitting on a nest at an altitude of c.520 m, showing that the species sometimes also nests in the lowlands (Jones et al. 1998). Food It is thought to be to be entirely frugivorous, feeding on a variety of small jungle fruits and berries (Wait 1931, Henry 1955), for example wild cinnamon (Legge 1880) and Symplocos cochinchinensis (Jones et al. 1998). It also occasionally visits village gardens to feed on jak fruit (Henry 1955) presumably Artocarpus heterophyllus. Breeding Clutches of eggs have been found in February and March and again in August, September, October and November (Whistler 1944), which continues to fit fairly closely with the observation of nests in both spring and autumn as late as October (Legge 1880). The species lays a single egg (Henry 1955). Jones et al. (1998) observed a recent fledgling in late August and an incubating bird in early September, on a nest that was considered very similar in design to that of the Common Wood-pigeon Columba palumbus, with a disorganised arrangement of twigs balanced on thin supporting branches. Migration The species makes seasonal movements, presumably following the availability of fruiting trees (Legge 1880, Wait 1931, Henry 1955), and in the past it was reported that migratory movement takes place just previous to the bursting of each monsoon (Legge 1880). During a recent survey at Delwala proposed reserve, it was not encountered for the first two weeks of the survey, but then it was seen daily, after apparently moving into the area to feed in fruiting bombu trees (Jones et al. 1998). Lewis (1898) noted that it became not uncommon in the dry zone when certain laurels are in fruit. THREATS The Sri Lanka Wood-pigeon is one of (now) seven threatened members of the suite of 23 bird species that are entirely restricted to the Sri Lanka Endemic Bird Area, threats and conservation measures in which are profiled by Stattersfield et al. (1998). Habitat loss The main threat to this species is the clearance and degradation of its forest habitat, and the reduction of its food supply (i.e. fruiting trees) as natural forests are replaced by monoculture plantations (Hoffmann 1984); a general survey of forest loss in Sri Lanka is made in the equivalent section under Red-faced Malkoha Phaenicophaeus pyrrhocephalus. 1534

5 Another concern is that forest die-back in the submontane and montane region is affecting the habitat of this species (Kotagama 1994), of which only some 719 km 2 were estimated to survive in the early 1990s (Legg and Jewell 1995). Preliminary and sporadic studies indicate that air pollution, causing acid clouds, rain and mist, mainly during the south-west monsoon, could be responsible (Hoffmann 1997). MEASURES TAKEN Legislation, habitat protection, research A brief review is made in the equivalent section under Red-faced Malkoha. Protected areas This species occurs in several national parks and forest reserves, most notably Sinharaja National Heritage Wilderness Area, a World Heritage Site which is actively protected under the jurisdiction of the Forest Department (IUCN/WCMC 1997), and Peak Wilderness and Udawattakele Sanctuaries (see Distribution). MEASURES PROPOSED Habitat protection, protected areas A brief review is made in the equivalent section under Red-faced Malkoha. Research A study relating the feeding ecology of this frugivore to forest phenology has been recommended, to help understand how it uses and depends on the remaining forest (Jones et al. 1998). Despite the wealth of data generated by the National Conservation Review in , much more detailed and wide-ranging surveys will be required to plan and monitor the management of individual conservation forests once they are established (IUCN/ WCMC 1997). 1535