The Thick-billed Green Pigeon (Treron curvirostra) is a common bird of Borneo's lowland rainforest and can be found up to an elevation of 1500m above sea level. This species has a wide distribution in around South East Asia stretching all the way to Hong Kong, Bangladesh and also to India. According to the IUCN Red List this species is evaluated as Least Concerned due to thier large range and population.
This species comes from the family of Columbidae, a big family of Pigeons and Doves. They are all mainly frugivorous birds and eat a wide variety of fruits, berries and also seeds. According to Smythies - The Birds of Borneo (1999), two subfamilies are represented in Borneo - The primarily arboreal and frugivorous Treroninae family represented by the green pigeons, fruit doves and imperial pigeons and the remainder in the predominantly terrestrial seed eating family Columbinae.
Sexes of this species differ greatly in where the back, mantle and upper inner wing coverts are maroon in the male but dark green in the female. Both though have a grey crown and a distinctive heavy bill with a red base.
This Thick-billed Green Pigeon "couple" photo is taken in the Sepilok Forest Reserve.
All photos taken with a Nikon D 300 + 70-300mm VR at ISO 400 f5.6