Great Slaty Woodpecker Mulleripicus pulverulentus Scientific name definitions

The Great Slaty Woodpecker of southeast Asia is among the largest woodpeckers in the world, surpassed in sheer size only by the likely-extinct Imperial Woodpecker (Campephilus imperialis) of Mexico. It combines this large size with a long bill, long neck, and long tail, and a slate-gray plumage with a peach-colored throat, for a truly unique appearance. This is a bird of lowland forests of varying types, but largely dependent on older forests with large trees. It is noisy and conspicuous, often occurring in pairs or small groups, but it is uncommon and local through most of its range. Its reliance on lowland forests subject to heavy deforestation, a low tolerance for forests modified by selective logging or agriculture, and large home ranges leaves this species' population vulnerable and declining.

Great Slaty Woodpecker is a very distinctive large woodpecker with a long bill, long neck, and long tail. The overall plumage is slate-gray with a variable number of small whitish feather tips (small pale spots often most prominent on ear coverts and hindneck) and a creamy buff chin and throat. The male has a red malar that the female lacks.

Few birds are unmistakeable, but Great Slaty Woodpecker is close. No other woodpecker combines the large bill, long neck and tail, overall plain dark gray plumage, and buff throat. Its congeners, Northern Sooty-Woodpecker (Mulleripicus funebris), Southern Sooty-Woodpecker (Mulleripicus fuliginosus), and Ashy Woodpecker (Mulleripicus fulvus), are most similar in overall appearance but do not overlap in range with Great Slaty Woodpecker or with each other.

Northern Sooty-Woodpecker is blue-glossed black. The female has the entire head blackish with fine white spots. The male has a dark red forehead and forecrown, lores, cheeks, malar region and front of ear coverts, usually some black feather bases showing, sometimes red not extending far on to crown. Spots are sometimes few or absent in both sexes. Southern Sooty-Woodpecker is much darker gray and has a pale yellow iris.

Woodpeckers have 10 functional primaries (numbered distally, from innermost p1 to outermost p10 and with the p10 reduced in length), 10 secondaries (numbered proximally, from innermost s1 to outermost s10 and including 3 tertials, numbered s8–s10 proximally or t1–t3 distally), and 12 rectrices (numbered distally on each side of the tail, from innermost r1 to outermost r6, and with the r6's vestigial or reduced in length). Geographic variation in plumages is slight (see Systematics); the following applies to all subspecies and is based on the descriptions of Short (1 Short, L. L. (1982). Woodpeckers of the World. Monograph Series 4, Delaware Museum of Natural History, Greenville, DE, USA. Close ), Winkler et al. (2 Winkler, H., D. A. Christie, and D. Nurney (1995). Woodpeckers: A Guide to the Woodpeckers, Piculets and Wrynecks of the World. Pica Press, Robertsbridge, UK. Close ), and Winkler and Christie (3 Winkler, H., and D. A. Christie (2002). Family Picidae (woodpeckers). In Handbook of the Birds of the World, Volume 7 (J. del Hoyo, A. Elliott and J. Sargatal, Editors), Lynx Edicions, Barcelona, Spain. pp. 296–555. Close ), as revised through examination of Macaulay Library images; see Pyle (4 Pyle, P. (2022). Identification Guide to North American Birds. Part I, Second Edition. Slate Creek Press, Forest Knolls, CA, USA. Close ) for age-related criteria in woodpeckers. Sequences of plumages are little studied in this species but appear to follow those of other woodpeckers. See the Molts section below for molt and plumage terminology. Appearance of sexes differs in all plumages (crown pattern only); definitive appearance typically assumed at Third Basic Plumage but possibly Fourth Basic Plumage in some individuals. Timing of plumages and plumage wear (generally more worn during breeding periods and fresher during non-breeding periods) relates to timing of molts, which in Great Slaty Woodpecker appear to be most frequent during fall (August-November) in the northern parts of the range but could occur year-round elsewhere (see Breeding: Phenology).

Natal Down

Woodpecker hatchlings are altricial and naked; no down develops (5 Short, L.L. (1982). Woodpeckers of the World. Monograph Series 4. Delaware Museum of Natural History, Greenville, Delaware, USA. Close ).

Juvenile (First Basic) Plumage

Juvenile Plumage (see image below) is duller and browner, particularly above and on the lower underparts, and the chin and throat are paler yellow than in later plumages. The crown and neck lack furrowed white-tipped feathers. Juvenile lower underparts feathering is filamentous due to lower barb densities, and juvenile flight feathers, especially rectrices, are narrower than basic feathers. Juvenile males show a red malar stripe that is larger than in later plumages, and sometimes shows some red in the crown (cf. ML377270031 ); these regions are gray in juvenile females.

The innermost juvenile primaries, p1 and sometimes p2, are usually replaced before chicks fledge from nest cavities. These are reported to be abbreviated (ca. 5–20 mm in length) in woodpeckers (6 Chapin, J. P. (1921). The abbreviated inner primaries of nestling woodpeckers. Auk 38(4):531–552. Close , 7 Sibley, C. G. (1957). The abbreviated inner primaries of nestling woodpeckers. Auk 74(1):102–103. Close , 8 Koenig, W. D., M. T. Stanback, and J. Haydock (2006). Abbreviated inner primaries: a sex-linked dimorphism in the Acorn Woodpecker. Journal of Field Ornithology 77(2):157–162. Close ), but it is possible that these feathers are not inherently short but are shed during the Preformative Molt before being fully grown, thus being at various lengths when replaced (4 Pyle, P. (2022). Identification Guide to North American Birds. Part I, Second Edition. Slate Creek Press, Forest Knolls, CA, USA. Close ).

Formative Plumage

Formative Plumage in woodpeckers is separated from later plumages by the retention of juvenile primary coverts, secondaries, and usually some outer secondary coverts (9 Pyle, P., and S. N. G. Howell (1995). Flight-feather molt patterns and age in North American woodpeckers. Journal of Field Ornithology 66(4):564–581. Close ,10 Pyle, P. (1997). Identification Guide to North American Birds. Part I. Slate Creek Press, Bolinas, CA, USA. Close ). In Great Slaty Woodpecker, female and male are similar to each sex in Definitive Basic Plumage except some juvenile secondary coverts, including some to all distal greater coverts, are usually or always retained, washed brown, contrasting with replaced, brighter gray, formative median and inner greater coverts. Outer primary coverts are uniformly juvenile and brownish, and juvenile outer secondaries are relatively worn by the end of the first cycle, as in other woodpeckers (9 Pyle, P., and S. N. G. Howell (1995). Flight-feather molt patterns and age in North American woodpeckers. Journal of Field Ornithology 66(4):564–581. Close , 4 Pyle, P. (2022). Identification Guide to North American Birds. Part I, Second Edition. Slate Creek Press, Forest Knolls, CA, USA. Close ). Tertials (if retained) can become very worn and abraded or might sometimes be replaced and contrast with more worn outer secondaries.

Second Basic Plumage

Second Basic Plumage (and possibly sometimes Third Basic Plumage) appear to be identifiable in Great Slaty Woodpecker, as in other woodpeckers (9 Pyle, P., and S. N. G. Howell (1995). Flight-feather molt patterns and age in North American woodpeckers. Journal of Field Ornithology 66(4):564–581. Close , 11 Siegel, R. B., M. W. Tingley, R. L. Wilkerson, C. A. Howell, M. Johnson, and P. Pyle (2016). Age structure of Black-backed Woodpecker populations in burned forests. Auk 133(1):69–78. Close , 4 Pyle, P. (2022). Identification Guide to North American Birds. Part I, Second Edition. Slate Creek Press, Forest Knolls, CA, USA. Close ). In both females and males, Second Basic Plumage can be separated from Definitive Basic Plumage by having some central juvenile primary coverts and probably sometimes juvenile secondaries retained and contrasting with replaced second basic feathers. Retained primary coverts may include 5–8 consecutive medial or outer feathers (among those corresponding to p3–p10), abraded and washed brown, contrasting with 1–3 consecutive replaced distal feathers (among those corresponding to p8–p10) which are fresher and grayer. Retained juvenile secondaries, when present, occur in a block of 1–6 consecutive feathers among s1–s6 (with s3 or s4 the last replaced); these are noticeably narrower, more faded brown, and abraded than replaced secondaries. From Formative Plumage further by uppewing secondary coverts uniformly basic, without molt limits.

In some woodpeckers, Third Basic Plumage can be identified by having 1-2 adjacent juvenile primary coverts retained, among those corresponding to p5-p7 (with that of p6 replaced last), along with two generations of basic coverts found proximal and distal to these feathers (12 Siegel, R. B., M. W. Tingley, R. L. Wilkerson, C. A. Howell, M. Johnson, and P. Pyle (2016). Age structure of Black-backed Woodpecker populations in burned forests. Auk 133(1):69–78. Close ; see also Figure 5F in 9 Pyle, P., and S. N. G. Howell (1995). Flight-feather molt patterns and age in North American woodpeckers. Journal of Field Ornithology 66(4):564–581. Close and Figure 119D in 4 Pyle, P. (2022). Identification Guide to North American Birds. Part I, Second Edition. Slate Creek Press, Forest Knolls, CA, USA. Close ). However, this may occur only in northern species that replace fewer feathers per year and might not occur or may occur only rarely in Great Slaty Woodpecker; study is needed.

Definitive Basic Plumage

Female

Dafinitive Basic Plumage overall primarily and uniformly gray. The feathers of the center crown, nape, and sides of the neck are furrowed and darker gray with white tips, forming a slightly corrugated or scaled appearance. The sides of the head (including the malar region) and remainder of upperparts, from back to uppertail coverts, are uniformly gray. The upperwing coverts are edged with slightly darker gray, more plumbeous in color. The rectrices, remiges, and primary are dusky with gray edging, overall appearing slightly darker than the upperparts. The chin and throat to the base of the neck is pale yellow, forming a distinct border with the lower sides of the head below the malar region. The remainder of the underparts are gray, with the furrowed darker and white-tipped feathers of the sides of the neck often reaching the sides and sometimes extending across the breast; the feathers of the ventral region and undertail coverts are sometimes fringed buff. The underwing coverts are gray (cf. ML203041201 ).

Definitive Basic Plumage is typically characterized by uniformly basic primary coverts and secondaries (without molt limits), or with mixed generations of basic feathers in these tracts, the older feathers not contrasting as strongly with replaced feathers as in Second Basic Plumage, the feathers usually not occurring in blocks, and often occurring asymmetrically between wings, as in other woodpeckers (9 Pyle, P., and S. N. G. Howell (1995). Flight-feather molt patterns and age in North American woodpeckers. Journal of Field Ornithology 66(4):564–581. Close , 10 Pyle, P. (1997). Identification Guide to North American Birds. Part I. Slate Creek Press, Bolinas, CA, USA. Close , 11 Siegel, R. B., M. W. Tingley, R. L. Wilkerson, C. A. Howell, M. Johnson, and P. Pyle (2016). Age structure of Black-backed Woodpecker populations in burned forests. Auk 133(1):69–78. Close ). Mixed replaced and retained basic secondaries and/or primary coverts indicates a bird in at least Fourth Basic Plumage.

Male

Similar to Definitive Basic Plumage in female except the malar region shows a distinct, ovate, pinkish-red to red patch, surrounded by gray feathering, and the feathers of the chin and throat average a deeper or brighter yellow.

Molt and plumage terminology follows Humphrey and Parkes (13 Humphrey, P. S., and K. C. Parkes (1959). An approach to the study of molts and plumages. Auk 76(1):1–31. Close ) as modified by Howell et al. (14 Howell, S. N. G., C. Corben, P. Pyle, and D. I. Rogers (2003). The first basic problem: a review of molt and plumage homologies. Condor 105:635–653. Close ). Under this nomenclature, terminology is based on evolution of molts along ancestral lineages of birds from ecdysis (molts) of reptiles, rather than on molts relative to breeding season, location, or time of the year, the latter generally referred to as “life-cycle” molt terminology (15 Jenni, L., and R. Winkler (2020). Moult and Ageing of European Passerines. Second edition. Bloomsbury, London, UK. Close , 16 Pyle, P. (2022). Defining moults in migratory birds: a sequence-based approach. Journal of Avian Biology 2022(5):e02958. Close ). Molts in Great Slaty Woodpecker are little studied but examination of Macaulay Library images indicates molting patterns consistent with most other woodpeckers ( 9 Pyle, P., and S. N. G. Howell (1995). Flight-feather molt patterns and age in North American woodpeckers. Journal of Field Ornithology 66(4):564–581. Close , 11 Siegel, R. B., M. W. Tingley, R. L. Wilkerson, C. A. Howell, M. Johnson, and P. Pyle (2016). Age structure of Black-backed Woodpecker populations in burned forests. Auk 133(1):69–78. Close , 4 Pyle, P. (2022). Identification Guide to North American Birds. Part I, Second Edition. Slate Creek Press, Forest Knolls, CA, USA. Close ), exhibiting the Complex Basic Strategy (cf. 14 Howell, S. N. G., C. Corben, P. Pyle, and D. I. Rogers (2003). The first basic problem: a review of molt and plumage homologies. Condor 105:635–653. Close , 17 Howell, S. N. G. (2010). Peterson Reference Guide to Molt in North American Birds. Houghton Mifflin Harcourt, Boston, Massachusetts, USA. Close ), including incomplete to complete prebasic molts and an incomplete preformative molt but no prealternate molts. Preformative and prebasic molts typically follow the breeding season in woodpeckers; in Great Slaty Woodpeckermolts appear to be most frequent during fall (August–November) in the northern parts of the range but could occur year-round elsewhere (see Breeding).

Prejuvenile Molt

Complete, in the nest cavity. Details of juvenile plumage development not known in Great Slaty Woodpecker.

Preformative Molt

As in other woodpeckers, the Preformative Molt may begin in the nest, before fledging, with replacement of the innermost 2 primaries (p1–p2; see Juvenile Plumage, above) and perhaps some other feathers (study needed). Following fledging, the molt includes all contour feathers, some to most or all inner upperwing lesser and median coverts, a variable number of greater coverts, and all primaries and rectrices, but no primary coverts or secondaries except sometimes to often 1–3 tertials, a replacement strategy unique to woodpeckers among avian preformative molts. Sequence of primary and rectrix replacement as described under Second Prebasic Molt.

Second Prebasic Molt

Incomplete. Includes all body feathers, upperwing secondary coverts, primaries, and rectrices, but not all primary coverts and, sometimes to often, not all secondaries. Primaries are replaced distally (p1 to p10) and rectrices are replaced from r2 distally to r6 on each side of the tail, followed by the central rectrices (r1), a sequence that enables the central rectrices, critical for stability on vertical tree trunks, to be replaced when other rectrices are fresher and stronger (18 Jones, A. W. (2010). Book review: Molt in North American birds. Condor 112(4):862–863. Close ). As in other woodpeckers (9 Pyle, P., and S. N. G. Howell (1995). Flight-feather molt patterns and age in North American woodpeckers. Journal of Field Ornithology 66(4):564–581. Close , 4 Pyle, P. (2022). Identification Guide to North American Birds. Part I, Second Edition. Slate Creek Press, Forest Knolls, CA, USA. Close ), 4 to 8 juvenile primary coverts can be retained in the center of the tract and 1–6 juvenile secondaries can also be retained, in a block among s1–s6, usually symmetrically in both wings (see image under Second Basic Plumage). Replacement of juvenile primary coverts and secondaries occurs in fixed sequence (P. Pyle unpublished data on genus Sphyrapicus): juvenile outer primary coverts are replaced convergently from both ends of the tract, terminating at the covert corresponding to p6 (differing from replacement sequence of primaries), and juvenile secondaries are replaced distally from s1 and proximally from the tertials (perhaps most often bilaterally from the second tertial, s9), terminating at s3 or s4.

In other woodpeckers, some individuals in Third Basic Plumage can continue to retain 1–3 juvenile primary coverts among the fourth to sixth coverts from the outside, corresponding to p5–p7 (11 Siegel, R. B., M. W. Tingley, R. L. Wilkerson, C. A. Howell, M. Johnson, and P. Pyle (2016). Age structure of Black-backed Woodpecker populations in burned forests. Auk 133(1):69–78. Close ; with that corresponding to p6 the last replaced), a pattern that should be looked for in a small proportion of Great Slaty Woodpeckers in Third Basic Plumage (see image under Third Basic Plumage).

Definitive Prebasic Molt

Incomplete to complete. All tracts are completely replaced except some primary coverts and/or secondaries in some individuals; 1–5 retained basic secondaries can occur among s1-s8 and a variable number of primary coverts can be retained at different positions along the tract (9 Pyle, P., and S. N. G. Howell (1995). Flight-feather molt patterns and age in North American woodpeckers. Journal of Field Ornithology 66(4):564–581. Close , 10 Pyle, P. (1997). Identification Guide to North American Birds. Part I. Slate Creek Press, Bolinas, CA, USA. Close , 11 Siegel, R. B., M. W. Tingley, R. L. Wilkerson, C. A. Howell, M. Johnson, and P. Pyle (2016). Age structure of Black-backed Woodpecker populations in burned forests. Auk 133(1):69–78. Close ). Sequence of flight-feather replacement as described under Second Prebasic Molt. Some basic primary coverts and secondaries are sometimes retained; these can occur throughout these tracts, may or may not occur in consecutive pairs or blocks as are retained juvenile feathers of earlier plumages, and are less often located symmetrically between the wings. Following incomplete molts, replacement within these tracts appears to occur in a Stafflemauser (stepwise)-like manner, whereby molt sequences continue where the previous prebasic molt arrested, while new sequences can commence (P. Pyle unpublished data on genus Sphyrapicus).

The following descriptions are based on those in the literature (1 Short, L. L. (1982). Woodpeckers of the World. Monograph Series 4, Delaware Museum of Natural History, Greenville, DE, USA. Close , 2 Winkler, H., D. A. Christie, and D. Nurney (1995). Woodpeckers: A Guide to the Woodpeckers, Piculets and Wrynecks of the World. Pica Press, Robertsbridge, UK. Close , 3 Winkler, H., and D. A. Christie (2002). Family Picidae (woodpeckers). In Handbook of the Birds of the World, Volume 7 (J. del Hoyo, A. Elliott and J. Sargatal, Editors), Lynx Edicions, Barcelona, Spain. pp. 296–555. Close ), along with examination of Macaulay Library images.

Bill and Gape

The bill is very strong, long, and chisel-tipped. In adults it is primarily grayish, often washed horn to yellowish on the lower mandible and base of the upper mandible, with a duskier culmen and a blackish tip. In juveniles the bill can be grayish with a yellowish tip. The gape appears to be pale and swollen in nestlings and this condition can persist but recedes in younger juveniles.

Iris and Facial Skin

At all ages the iris is brown. In other woodpeckers, juvenile iris color is duller and gray but deeper and tinged reddish in adults; slight differences such as this should be looked for in Great Slaty Woodpecker. The orbital skin is gray.

Tarsi and Toes

At all ages the legs and feet are grayish to blue-gray or greenish gray with dark gray claws.

Linear Measurements

Total length: 45–50 cm.

Measurements (in mm) from Winkler et al. (19 Winkler, H., D. A. Christie, and D. Nurney (1995). Woodpeckers: A Guide to the Woodpeckers of the World. Houghton Mifflin, Boston, MA, USA. Close ): wing 215–250, tail 134–162, bill 60–65, tarsus 36–41.

Mass

360–563 g (19 Winkler, H., D. A. Christie, and D. Nurney (1995). Woodpeckers: A Guide to the Woodpeckers of the World. Houghton Mifflin, Boston, MA, USA. Close ).

Geographical variation not well marked, and individual variation makes subspecies delimitation difficult; size varies only slightly and inconstantly throughout range. Northwestern populations (Himachal Pradesh to northern Assam) are sometimes separated as subspecies mohun on basis of darker coloration, but some individuals from Myanmar and Thailand appear identical (19 Winkler, H., D. A. Christie, and D. Nurney (1995). Woodpeckers: A Guide to the Woodpeckers of the World. Houghton Mifflin, Boston, MA, USA. Close ). Subspecies harterti and pulverulentus intergrade in peninsular Thailand, intermediates from which previously separated as subspecies celadinus.

Three subspecies recognized (20 Clements, J. F., P. C. Rasmussen, T. S. Schulenberg, M. J. Iliff, T. A. Fredericks, J. A. Gerbracht, D. Lepage, S. M. Billerman, B. L. Sullivan, and C. L. Wood (2023). The eBird/Clements checklist of Birds of the World: v2023. Cornell Laboratory of Ornithology, Ithaca, NY, USA. Close ).

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SUBSPECIES

Mulleripicus pulverulentus mohun Scientific name definitions

Systematics History

Mulleripicus pulverulentus mohun Ripley, 1950, Proceedings of the Biological Society of Washington 63 p. 103.―Jamu Ghat on the Bheri River, western Nepal (21 Ripley, S. D. (1950). New birds from Nepal and the Indian region. Proceedings of the Biological Society of Washington 63:101-108. Close ).

Distribution

Lowlands and foothills at the base of the Himalayas, from Uttarakhand, India, east through Nepal to Assam.

Identification Summary

Differs from subspecies harterti in being darker gray above and especially below, with a deeper crimson malar (21 Ripley, S. D. (1950). New birds from Nepal and the Indian region. Proceedings of the Biological Society of Washington 63:101-108. Close , 19 Winkler, H., D. A. Christie, and D. Nurney (1995). Woodpeckers: A Guide to the Woodpeckers of the World. Houghton Mifflin, Boston, MA, USA. Close ).

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SUBSPECIES

Mulleripicus pulverulentus harterti Scientific name definitions

Systematics History

Mulleripicus puiverulentus harterti Hesse, 1911, Ornithologische Monatsberichte 19 p. 182.―Assam, Burma to Tenasserim (22 Hesse, E. (1911). Neue Spechtformen. Ornithologische Monatsberichte 19:181–184. Close ).

Distribution

Himalayan foothills in northern Assam and in North Cachar Hills, east through northern Myanmar and southern China (southern Yunnan) and northwestern Vietnam, south to peninsular Thailand and southern Vietnam.

Identification Summary

Described under Plumages.

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SUBSPECIES

Mulleripicus pulverulentus pulverulentus Scientific name definitions

Systematics History

Picus pulverulentus Temminck, 1826, Nouveau recueil de planches coloriées d'oiseaux, pour servir de suite et de complément aux planches enluminées de Buffon livr. 66 pl. 389.―Java and Sumatra (23 Temminck, C. J. (1825). Nouveau Recueil de Planches Coloriées D'oiseaux, Pour Servir de Suite et de Complément aux Planches Enluminées de Buffon. F. G. Levrault, Libraire-Éditeur, Paris Close ).

Distribution

Peninsular Thailand south through Peninsular Malaysia, eastern Sumatra, western Java, Natuna Islands, Borneo, and Palawan.

Identification Summary

Similar to harterti but darker grayish-black overall (19 Winkler, H., D. A. Christie, and D. Nurney (1995). Woodpeckers: A Guide to the Woodpeckers of the World. Houghton Mifflin, Boston, MA, USA. Close ).

Within the genus Mulleripicus, Great Slaty Woodpecker is most closely related to Northern Sooty-Woodpecker (Mulleripicus funebris), and the genus overall is most closely related to Dyocopus (24 Shakya, S. B., J. Fuchs, J.-M. Pons, and F. H. Sheldon (2017). Tapping the woodpecker tree for evolutionary insight. Molecular Phylogenetics and Evolution 116:182–191. Close ).

Himalayan foothills from northwestern India (Uttarakhand) east through Nepal, northern Assam, and North Cachar Hills, extending further east through northern Myanmar and southern China (southern Yunnan) to northwestern Vietnam, then south down the Thai-Malay Peninsula and south to southern Vietnam, largely absent from lowlands of central Thailand. Range continues south on islands in the Greater Sundas (Sumatra, Java, Natuna Islands, Borneo) and east to Palawan.

Primary semi-open moist deciduous and tropical evergreen forests, adjacent secondary forest, clearings with scattered tall trees; also similar, almost park-like, woodland. Dipterocarp and teak forests preferred in some areas; mature sal (Shorea) forest, swamp-forest and tall mangroves. Generally shuns selectively logged forest (25 Lambert, F. R., and N. J. Collar (2002). The future for Sundaic lowland forest birds: long-term effects of commercial logging and fragmentation. Forktail 18:127–146. Close ) and is strongly dependent on forest with large-diameter trees (26 Lammertink, M., Prawiradilaga, D.M., Setiorini, U., Naing, T.Z., Duckworth, J.W. and Menken, S.B.J. (2009). Global population decline of the Great Slaty Woodpecker (Mulleripicus pulverulentus). Biological Conservation. 142(1): 166-179. Close ). Most frequent in lowlands and lower hills below 600 m, but also occurs in montane habitats up to 1100 m (foothills of Himalayas), occasionally to 2000 m.

Predominantly ants; also other insects, such as stingless bees, termites (27 Lammertink, M. (2004). Grouping and cooperative breeding in the Great Slaty Woodpecker. Condor. 106(2): 309-319. Close ) and larvae of wood-boring beetles. Small fruits possibly eaten at times. Usually in pairs, and regularly in noisy family parties of 3–6 birds, sometimes more (12), roaming through forest, but roost separately 200–800 m apart (27 Lammertink, M. (2004). Grouping and cooperative breeding in the Great Slaty Woodpecker. Condor. 106(2): 309-319. Close ); sometimes associates with other woodpeckers, such as White-bellied Woodpecker (Dryocopus javensis) and Greater Flameback (Chrysocolaptes guttacristatus) when foraging. Forages mainly in tall trees, including solitary ones in open areas; flies long distances to reach these (thus, home range very extensive); sometimes visits smaller trees and saplings at low levels, not infrequently close to ground. Climbs trunks and larger branches slowly, pausing frequently at crevices and other depressions and cracks in bark; may perch crosswise in crown, even on small branches. Gleaning is the most frequent technique, and the long neck and bill assist it in reaching a long way out. Other foraging techniques include probing, pecking, prying-off of bark; also hammering with powerful loud blows to excavate wood, and young birds observed attempting to catch flying insects (28 Thompson, P. M., and D. L. Johnson (2003). Further notable bird records from Bangladesh. Forktail 19:85–102. Close ). In foraging groups, females principally climb and search, males instead hammering, pecking and flaking, and grouping is speculated to be induced by cooperatively searching for and exploiting infrequent but highly profitable food sources (27 Lammertink, M. (2004). Grouping and cooperative breeding in the Great Slaty Woodpecker. Condor. 106(2): 309-319. Close ). Does not remain long at one spot to peck or hammer. Relatively nimble when foraging among branches, but climbs almost in “slow motion”.

Loud whinnying cackle of 2–5 (most commonly four) notes , “woikwoikwoikwoik”, initial note often slightly higher-pitched, final one distinctly lower, shorter version with consecutive notes dropping more in pitch, frequently in flight; single “dwot” calls, variable, perched or in flight; low soft mewing notes by partners at very close contacts; “ta-whit” or “dew-it” in more agonistic situations (with head-swinging). Drumming not certainly reported.

March–May in west, March–August in Southeast Asia; June–August (29 Mann, C. F. (2008). The Birds of Borneo: An Annotated Checklist. B.O.U. Checklist 23. British Ornithologists’ Union, and British Ornithologists’ Club, Peterborough. Close ) and December–February on Borneo (27 Lammertink, M. (2004). Grouping and cooperative breeding in the Great Slaty Woodpecker. Condor. 106(2): 309-319. Close ). Displays include strange-looking head-swinging, head appearing to lag behind body in its swinging movement; during chases, wings extended widely, tail also spread. Nest hole excavated by both sexes, although male does most of the work, very high up (range 9–45 m) in tree (e.g. Kompassia excelsa, Sonneratia, Lumnitzeria) (30 Wells, D. R. (1999). The Birds of the Thai-Malay Peninsula. Volume 1. Non-passerines. Academic Press, London, UK. Close ), in large trunk or branch, entrance hole ca. 10 cm across; old nest occasionally reused, probably only when new one usurped, and sometimes adopts or adapts cavity previously used by another hole-nester, e.g. Dollarbird (Eurystomus orientalis) or Brown Boobook (Ninox scutulata) (30 Wells, D. R. (1999). The Birds of the Thai-Malay Peninsula. Volume 1. Non-passerines. Academic Press, London, UK. Close ). Occasionally single helpers have been observed at nests (27 Lammertink, M. (2004). Grouping and cooperative breeding in the Great Slaty Woodpecker. Condor. 106(2): 309-319. Close ). Clutch 2–4 white (30 Wells, D. R. (1999). The Birds of the Thai-Malay Peninsula. Volume 1. Non-passerines. Academic Press, London, UK. Close ) eggs; both sexes incubate, and both or all three (27 Lammertink, M. (2004). Grouping and cooperative breeding in the Great Slaty Woodpecker. Condor. 106(2): 309-319. Close ) feed chicks together at rate of once every 93 ± 54 minutes; incubation and fledging periods not known; fledged young remain with parents for some time, probably until next breeding cycle commences.

VULNERABLE. Population estimated in 2005 at 26,000–550,000 individuals (subdivided into estimates of 259,205 of subspecies harterti and 144,113 of nominate) within overall range of ca. 2.5 million km², and it has been suggested that ca. 90% of the global population has been lost over the past 100 years, with only tiny numbers likely to remain in Bangladesh, Bhutan, China, Nepal and Singapore (26 Lammertink, M., Prawiradilaga, D.M., Setiorini, U., Naing, T.Z., Duckworth, J.W. and Menken, S.B.J. (2009). Global population decline of the Great Slaty Woodpecker (Mulleripicus pulverulentus). Biological Conservation. 142(1): 166-179. Close ). Uncommon in northern Indian Subcontinent, where largely restricted to natural sal forests and virtually absent from production forests (31 Kumar, R., Shahabuddin, G. and Kumar, A. (2011). How good are managed forests at conserving native woodpecker communities? A study in sub-Himalayan dipterocarp forests of northwest India. Biological Conservation. 144(6): 1876-1884. Close ); no records in Bangladesh between 1977 and 2003, when rediscovered in Dulahazara Safari Park (28 Thompson, P. M., and D. L. Johnson (2003). Further notable bird records from Bangladesh. Forktail 19:85–102. Close ); uncommon to fairly common, but often rather local, in Southeast Asia, practically extinct in Singapore; rare in southern China; exceedingly rare in Sumatra and Java, and not likely to survive, but somewhat more common in Borneo; uncommon and decreasing in Philippines. Known from total of 15 range states, but recently suggested that ca. 70% of global population occurs in just four countries—Myanmar, Indonesia, Cambodia and Malaysia—of which the three last-named have high annual rates of deforestation and loss of old-growth forest (26 Lammertink, M., Prawiradilaga, D.M., Setiorini, U., Naing, T.Z., Duckworth, J.W. and Menken, S.B.J. (2009). Global population decline of the Great Slaty Woodpecker (Mulleripicus pulverulentus). Biological Conservation. 142(1): 166-179. Close ). Although generally uncommon or rare throughout its range, and species is not usually found in forest fragments smaller than 1000 ha (25 Lambert, F. R., and N. J. Collar (2002). The future for Sundaic lowland forest birds: long-term effects of commercial logging and fragmentation. Forktail 18:127–146. Close ), but can be conspicuously noisy where present; not likely to be overlooked. Occurs in many protected areas, e.g. Corbett, Namdapha and Rajaji (32 Mohan, D. and Kumar, R. (2010). Breeding birds of Kothri valley, eastern Garhwal Hitnalayan foothills, India. Forktail. 26: 75-81. Close ) National Parks (India), Gunung Palung and Alaungdaw Kathapa National Parks (Myanmar) (26 Lammertink, M., Prawiradilaga, D.M., Setiorini, U., Naing, T.Z., Duckworth, J.W. and Menken, S.B.J. (2009). Global population decline of the Great Slaty Woodpecker (Mulleripicus pulverulentus). Biological Conservation. 142(1): 166-179. Close ), Khao Yai and Nam Nao National Parks (Thailand), Nam Bai Cat Tien National Park (Vietnam), Taman Negara National Park and Panti Forest Reserve (Peninsular Malaysia), Aas Purwo National Park (Java), Danum Valley Conservation Area, Gunung Mulu, Gunung Palung, Kutai, Similajau and Tanjung Puting National Parks (29 Mann, C. F. (2008). The Birds of Borneo: An Annotated Checklist. B.O.U. Checklist 23. British Ornithologists’ Union, and British Ornithologists’ Club, Peterborough. Close ) (Borneo) and St Paul’s Subterranean River National Park (Palawan, Philippines). Extensive habitat destruction seems likely to have led to the demise of this magnificent woodpecker in Sumatra (if indeed it ever occurred on the mainland) (26 Lammertink, M., Prawiradilaga, D.M., Setiorini, U., Naing, T.Z., Duckworth, J.W. and Menken, S.B.J. (2009). Global population decline of the Great Slaty Woodpecker (Mulleripicus pulverulentus). Biological Conservation. 142(1): 166-179. Close ), where probably now restricted to offshore islands (e.g. Riau Archipelago) (33 Holmes, D. A. (1996). Sumatra Bird Report. Kukila 8(1):9–56. Close ), and there seems little chance that it can fare much better in Java. Hunting is speculated to be one cause of decline in some parts of species’ range (26 Lammertink, M., Prawiradilaga, D.M., Setiorini, U., Naing, T.Z., Duckworth, J.W. and Menken, S.B.J. (2009). Global population decline of the Great Slaty Woodpecker (Mulleripicus pulverulentus). Biological Conservation. 142(1): 166-179. Close ). Densities are naturally low, since it lives in large home ranges; it should be secure in the mainland parts of its current range, provided reasonably large tracts of habitat remain intact.

Chuenchom Hansasuta received a Doctor of Dental Surgery from Chulalongkorn University. During her long and distinguished career in dentistry, she studied and practiced in places such as Thammasat University (Thailand), State University of New York at Buffalo (USA), and University of Connecticut Health Center (USA) and retired in 2020. Chuenchom always had an intense curiosity for birds that over time, evolved into an acute interest in plumages. She has long been active in education and volunteering, becoming chairwoman of The Flyway Foundation and actively engaging and educating the public in the study of birds and their plumages.