Unfortunately, these pigeons, which were feeding at a fruiting tree, were not vocalizing which makes their identification somewhat problematic. They are either Ruddy Pigeon C. subvinacea or Plumbeous Pigeon C. plumbea.

I also asked for help from Bird Forum and you can follow the thread of the discussion at http://www.birdforum.net/showthread.php?t=24949.

The strongest evidence is from Rasmus Boegh in favour of Plumbeous Pigeon. He says:
"...there is no doubt that Plumbeous can have dark eyes. I saw a single individual with brown eyes (ID'ed via voice) in Venezuela - an area where all other Plumbeous I saw had pale eyes. All Plumbeous I have seen in Ecuador (both sides of the Andes), Peru, Bolivia & Brazil have also been pale-eyed. So, no doubt that they usually have pale eyes (at least in the localities I have been to). Having said that, I don't think anyone disputed that they can have darker eyes (as also mentioned in Birds of Venezuela and Birds of Peru). Therefore, I don't think this is a "direct ID". Rather, an ID via elimination. Personally, I have no doubt the birds are Plumbeous, quite simply because I have been unable to find any indications supporting that this strikingly pale eye-colour ever occur in Ruddy. Hence, I believe Ruddy can be eliminated as a possibility, leaving Plumbeous. This would have been much more complicated if the bird had been dark-eyed, but luckily it is not...".

So I am going with Rasmus's view. If you have anything further to add, please let me know at arthur@arthurgrosset.com or through the Bird Forum site.