Greetings from Lisa Arensen. I do not have a beautiful photograph like Jeff--kudos to you, Jeff!
However, on April 13th, I saw a pair of white-winged ducks while with Ben Davis of ADRA, in a prospective ecotourism site in central Prea Vihear. To be precise, we were walking along Stung Bak Make, several miles from Ta Bos village in Sadou commune, Sangkhum Tmei district. The commune chief claims there are three pairs of white-winged ducks that roost along this quiet wooded river, but we can only confirm the one pair we saw. The area is dry deciduous forest with some evergreen patches, and we had hiked cross-country around five kilometres from the oxcart trail where we left the trail before we saw the ducks (at around noon). There is no trail that runs consistently along the stung/river, although there are resin tappers' and hunters' paths that wind in and out, so we had been coming down to the riverside intermittently as the terrain permitted. It had been a long hot morning, and we had actually given up on finding the ducks and were inspecting burned resin trees when we accidentally flushed a pair--they were quite close to us and we both got good looks at them as they flew away. We did not get a photograph, and neither of us has seen them before, but I feel confident that they were white-winged ducks, not simply because of habitat but also because of their large size, their white heads with dark spots, and their large white wing patches. Area villagers had reported that the tia brai roost on this river and that hunters hear them calling at night. Sadly, six of these rare ducks were reported as killed and eaten last year (this is an unverified number reported by the commune chief), and the commune chief remarked that ducklings are rarely seen. Local villagers hunt with dogs, so Ben suspects that this may be the fate of any ducklings, which I gather is also a threat to other white-winged ducks in Cambodia?