(1818) Pernis ptilorhynchus ptilorhynchus.
THE JAVAN CRESTED HONEY-BUZZARD.
Falco ptilorhynchus Temm., Pl. Col., pl. 44,1823 (Java). Pernis cristatus. Blanf. & Oates, iii; p. 406 (part.).
Vernacular names. None recorded.
Description. The plumage of the adults is more variable than in any other of our Indian Raptores and might almost be described as polymorphic. Adults may, -however, be always recognized by the tail, which is narrowly tipped pale with a broad subterminal band of black; this is followed, by a slightly broader band of mottled white, grey and brown and this by another broad band of black; between this black band and the brown base is a narrow band of mottled pale brown and white or grey.
In one phase the head is very dark brown, changing to black on the nuchal crest; the face, sides of the head and neck grey, chin and throat grey, the white bases showing everywhere, changing to blackish on the fore-neck and with mesial and lateral black bands; primaries edged with silver-grey and tipped blackish and all quills with white internal bases, barred with blackish ; lower parts brown with white bars; in some cases these are concealed, in others show plainly everywhere; in a few specimens the lower parts appear to be boldly barred black and white from the breast to the vent, this being the form described as tweedalei.
Another phase has. the breast pale brown, with broad central streaks, the chin and throat almost white with black shafts and some black patches on the fore-neck; the remainder of the lower parts white with broad bars of pale fulvous brown, generally with narrow black shaft-stripes throughout; between this and the last phase there is every intermediate stage.
Yet another phase has the whole lower plumage rufous except for the mesial and lateral black throat-stripes.
Colours of soft parts. Iris golden-yellow to orange-red; browner in young birds; bill blackish" or slaty-black, the base plumbeous ; cere bluish-slaty; legs and feet yellow, claws black.
Measurements. Wing 398 to 455 mm.: tail 241 to 263 mm.: tarsus 44 to 49 mm.; culmen 30 to 36 mm.; a female from Mindanao has a tail of 298 mm. and tarsus of 59 mm.
Young birds have the upper plumage brown, each feather edged and tipped paler or white, very broadly so on the scapulars, wing-coverts and inner secondaries; the head and neck is often more white than brown, the feathers of the crown being brown with white bases and tips and black central streaks; the lores and a line through the eye black; the underparts are white or fulvous-white, with a few fine streaks on the breast and flanks and the latter also with a few pale brown bars.
A pair of nestlings of the next race brought to me in down moulted but into this stage but without any bars or striations ; in the following spring they assumed a brown upper plumage with hardly any pale edgings but the under plumage became pale brown or fulvous, with streaks of dark brown plentiful on the breast and much white barring on the lower breast, flanks and abdomen; the tail remained as in' the first stage,' dark brown with a white tip and numerous 'pale brown bars becoming white on the inner webs.
The third year they became more uniformly dark and the tail became almost as definitely and broadly banded as in the adult but the basal half was much,broken and barred.
The fourth spring one bird moulted into the all brown phase and the other into the third phase described above.
Distribution. Java, Sumatra, Borneo, Philippines, through Malay States to Tenasserim. I cannot separate celebensis from this form and it should be noted that the characters relied on by Sharpe to diagnose the species of Pernis are all individual and not specific or even subspecific characters.
Nidification. Nothing recorded.
Habits. Apparently very much the same as those of the next race but is found far more frequently in forest. Like its Indian cousin, in addition to honey, it eats small reptiles, birds and mammals.
* See Robinson and Kloss, Journ. Nat. Hist. Soc. Siam, v, p. 94, 1923.