Bioacoustics of Macropygia amboinensis

Range M. a. cinereiceps Biak, Supiori, Rani, Yapen; M. a. maforensis Numfor ; M. a. griseinucha Mios Num. Taxonomy Mayr (1941) placed the Biak population in M. a. kerstingi which Beehler & Pratt (2016) synonymised with M. a. cinereiceps . Ng et al . (2016) reviewed species limits among Indo-Pacific Macropygia using bio-acoustic data and placed the Biak population with maforensis (Beehler & Pratt 2016) . However, no sound-recordings from Biak were included; see below. Status Resident. Widespread and generally common; obtained by most collectors and recorded by most visitors, in primary, secondary and selectively logged forest. KDB saw it up to c . 335 m on Supiori in primary forest on limestone karst. 6 August 2015 : two on Rani ( N. Voaden , eBird checklist S24512191). Voice Recordings made on Biak (Xeno-canto: XC75908‒75909 [SvB], XC40677 [P. Aberg], XC582453 [K. Behrens]; and KDB [unpubl.]) are characterised by a series of identical, upslurred disyllabic ‘whoops’ repeated ad nauseum at a rate of c .5 notes over 3.5 seconds. Recordings of maforensis on Numfor (F. Lambert (XC167004‒167005) are a noticeably different, much more rapid series of single (i.e., non-disyllabic) notes, 11 in five seconds, on a very similar pitch. Recordings on Biak closely recall the disyllabic notes of birds from Yapen (KDB), the Mamberamo (SvB; XC140940) and Timika (SvB) areas, all in the range of ‘ kerstingi ’. Moreover, kerstingi -plumaged birds in the Eastern Highlands reportedly utter ‘double-noted hoots’ ( Diamond 1972 ), whilst birds with similar morphology from the Fly River ( cf . Rand 1942 , Woxvold & Bishop 2020 ) clearly differ from the monosyllabic notes of cinereiceps sensu stricto in far eastern New Guinea ( cf . Gregory 2017 , Woxvold & Bishop 2020 ). This suggests vocal differentiation, although there appears to be sufficient variation that further analysis is warranted. However, based on this preliminary assessment, we disagree with Ng et al. (2016) that the Biak population should be placed with maforensis but concur with Beehler & Pratt’s (2016) assignment of it to cinereiceps , albeit with the caveat that kerstingi may represent a valid subspecies.