White-breasted Mesite Mesitornis variegatus Scientific name definitions

31 cm; 103–111 g, female may be smaller and lighter, but not apparent in field. Pale creamy to white supercilium and throat; breast also pale cream, sometimes tinged rufous; black crescents on sides of breast and upper belly; back rufous-brown. Development of rufous breastband linking moustachial stripes is highly variable in extent and tone in northernmost population; birds of southernmost population have thick, bright bands. Some birds have noticeably grey nape. Bare skin round eye grey to bright blue. Such variability might be related to age or sex, or both, but nothing known. Bill intermediate in length between those of M. unicolor (with which present species has recently been found in sympatry at one site in E rainforest) (1 Thompson, P. M., and M. I. Evans (1992) The threatened birds of Ambatovaky Special Reserve, Madagascar. Bird Conservation International 2: 221-237. Close ) and Monias benschi, and much less curved than that of latter; paler underparts than M. unicolor. No seasonal variation, nor significant changes due to feather wear. Juvenile up to 1–2 months old similar to adult, but throat and supercilium yellow-buff with smudgy blackish longitudinal marks; thenceforth probably indistinguishable from adults.

Madagascar. Known only to occur in three widely separated small areas in W & N, between 12°44’ S (Analamera) and 20° S (Menabe forests); however, single anomalous record from E (Ambatovaky).

Primarily found in dry western deciduous forests, at altitudes below 150 m. Single recent anomalous record from lowland rainforest at 350 m.

No evidence to suggest that species is anything other than sedentary; groups maintain same territory year-round, at least in some sites.

Mainly feeds on small adult and larval invertebrates, but also takes some plant matter. Food items recorded as being taken, in order of frequency: unidentified seeds, 3–5 mm in diameter; crickets, 5–10 mm; cockroaches, 5–10 mm; spiders, 5–15 mm; beetles, adults and larvae, latter up to 20 mm long; centipedes; mantids; and moths and flies. Seeds made up 17% of items in number, rest invertebrates. Other items recorded include dwarf terrestrial chamaeleon (Brookesia) and crystallized exudate of homopteran bug nymphs of family Flattidae. Species inhabits seasonal environment and diet accordingly varies: small invertebrate prey commoner in dry season, larger prey more frequent in wet season. Forages on forest floor , gathering food mainly from leaf litter, but also from low vegetation. Main foraging techniques include gleaning from surface of leaf litter, low vegetation or spiders' webs, leaf-turning and leaf-lifting; also leaf-thrashing and sometimes a short chase of flushed invertebrates; occasionally probes into soil, mainly in dry season. See Family Text .

Considered to be highly vocal, with song  usually given as a series of loud whistles in duet : "weeeeee titititi ... weee titititi ... titit wee titit weee ....... weee tititititi, which typically accelerates, has a slightly electrical quality  and appears to become more excited, before falling away at the end (3 Morris, P., and F. Hawkins (1998). Birds of Madagascar: a photographic guide. Pica Press, Robertsbridge, UK, and Yale University Press, New Haven, CT, USA. Close ). Gives a low "cluck" (1 Thompson, P. M., and M. I. Evans (1992) The threatened birds of Ambatovaky Special Reserve, Madagascar. Bird Conservation International 2: 221-237. Close ) or "shik" (3 Morris, P., and F. Hawkins (1998). Birds of Madagascar: a photographic guide. Pica Press, Robertsbridge, UK, and Yale University Press, New Haven, CT, USA. Close ) in alarm; a slightly growling "whaark" may be uttered in similar contexts  .

Active nests found Oct–Apr, with egg-laying peaking Nov–Jan. Apparently monogamous, with long-lasting pair-bond. Nest is loose flat platform of 20–30 sticks; placed 1–3 m up in shrub layer, in clump of dead vegetation or live bush. Clutch 2 eggs (average 1·92, n = 39); up to three cluches per breeding season; females incubate during daylight only, and males from early afternoon to next morning; incubation period 25 days; both sexes provide food to nestlings, at similar rates (4 Gamero, A., Székely, T. and Kappeler, P.M. (2014). Delayed juvenile dispersal and monogamy, but no cooperative breeding in white-breasted mesites (Mesitornis variegata). Behavioral Ecology and Sociobiology. 68: 73–83. Close ). Chick uniform red-brown (not black as previously suggested) (5 Appert, O. (1995). Zum Dunenkleid der Nakas (Mesitornithiformes) von Madagaskar [The down plumage of Mesitornithiformes chicks.]. Der Ornithologische Beobachter. 92: 455–458. In German with English summary. Close ). Post-fledging care probably long; birds live as family groups of breeding pair and most recent young, but there is no evidence of cooperative breeding (4 Gamero, A., Székely, T. and Kappeler, P.M. (2014). Delayed juvenile dispersal and monogamy, but no cooperative breeding in white-breasted mesites (Mesitornis variegata). Behavioral Ecology and Sociobiology. 68: 73–83. Close ).

VULNERABLE. Population thought to be in rapid decline. Does not occur in at least some seemingly suitable forests between known centres; this may be due to past forest clearance and subsequent regeneration. Combined population at two main centres (Ampijoroa and Menabe) originally estimated at 7000–38,000 breeding adults, but number of mature individuals now thought to be as few as 5300 within overall range of 6100 km². Group density, group size and site fidelity highest in selectively logged forest near rivers in Menabe area, and in undisturbed plateau forest at Ampijoroa. Populations at northern sites (Ankarana and Analamera) probably much smaller. Numbers at Ambatovaky and other eastern sites, if any, unknown, and probably all populations away from two main centres are relictual. Major threats stem from habitat loss, caused, in order of importance, by subsistence agriculture, bush fires and intensive commercial exploitation. Birds hunted, and even taken when incubating. Selective logging may not itself threaten species, but increased hunting pressure, as result of improved access, may reduce habitat quality in logged areas, and the species appears incapable of recolonizing areas of regenerating forest. Ankarana, Analamera, Ambatovaky, Ankarafantsika, and Andranomena (part of Menabe) are all officially protected and listed as Important Bird Areas; other parts of Menabe subject to intensive commercial exploitation, as is much of Ankarafantsika. All three forests in W are subjects of current open-ended conservation management initiatives, with varying degrees of success.