Consumption of pawpaw 'Carica papaya' foliage by Christmas Island Imperial-Pigeons 'Ducula whartoni': Health or hunger?

The ecology of the endemic Imperial-Pigeon occurring on Christmas Island, Ducula whartoni, is poorly known. Here, I report repeated episodes of consumption of leaves of the introduced Pawpaw Carica papaya in observations across the period July 2012 to June 2013. Folivory is unusual in the predominantly frugivorous Ducula fruit-pigeons. There may be three reasons for such regular folivory: (1) leaves were taken when fruit was unavailable or severely limited, (2) fruit was available but provided inadequate nutrition, or (3) fruit was available and adequately nutritious, but Pawpaw leaves were consumed because of their therapeutic value. This study did not provide sufficient critical evidence to test these alternatives.