Calyptomena viridis, Raffles, 1822

Gulson-Castillo, Eric R., Pegan, Teresa M., Greig, Emma I., Hite, Justin M., Hruska, Jack P., Kapoor, Julian A., Orzechowski, Sophia C., Shipley, J. Ryan & Winkler, David W., 2019, Notes on nesting, territoriality and behaviour of broadbills (Eurylaimidae, Calyptomenidae) and pitas (Pitidae) in Tawau Hills Park, Sabah, Malaysian Borneo, Bulletin of the British Ornithologists’ Club 139 (1), pp. 8-27 : 10-11

GREEN BROADBILL Calyptomena viridis

Encountered infrequently in the lowlands of Tawau Hills in 2012 and 2013 (despite regular visits to fruiting trees), but it was more common in the highlands in 2013. We observed the species ten times between 24 June and 26 July 2012, and twice in 2013, the latter during four visits to a strangler fig tree from 27 February to 4 March, and on a single visit to a fig tree 350 m away on the other side of a ridge on 7 April. Green Broadbills responded once to playback in 2012 (see below), but never in 2013. They were usually solitary, but we saw them in pairs several times, including on 27 February 2013, when a pair visited the understorey and made complex soft vocalisations while just out of sight. During a three-day excursion to Gunung Lucia in 2013, we heard c.6 individuals at 850–940 m.

The species’ scarcity in the primary forest lowlands of Tawau Hills during our visits (including July 2012) contrasts with the abundant breeding activity (and responsiveness to playback) in a degraded lowland forest in July 2014 ( Pegan et al. 2018). Others have suggested that Green Broadbills are nomadic, as evidenced by broad and sporadic elevational records, and apparent rarity when fruit is scarce ( Medway & Wells 1970, Fogden 1972; but see Lambert 1989). That the species tended to appear suddenly at Tawau Hills in places that they had not been before, and then disappear again, is consistent with this hypothesis.

On 24 June 2012, JAK observed a Green Broadbill respond to an imitation of its calls with a wing-raising display. JAK imitated the soft vocalisations of a lone male calling in the midstorey, whereupon the bird immediately flew directly and repeatedly overhead (c. 5 m above ground). Each time the bird perched, it raised both wings so that their dorsal surfaces either touched or almost did so. Other displays in which Green Broadbills use their wings in various ways were summarised by Lambert & Woodcock (1996) and Wells (2007), although none was in response to vocal imitations or playback.