Hi Mike & Nikolas, I’ve looked through my photos and I took 2 sets of shots, one from 10.40:39 – 10.41:27 and the second from 10.44:07 – 10.44:50, seen at the link below. http://www.pbase.com/rob_hynson/eaglehawk_neck_pelagics In the first set of photos I see the neck smudge/irregularity Nikolas refers to when viewing the bird from the right and the mandibular unguis does not look that dark. The second set of photos (which are much closer) shows a much darker mandibular unguis, of the photos posted from the second set, only one is in flight viewing the bird from the right, I think the neck smudge is there but its not a great angle for comparison. Also from the second set of photos, the bird on the water looks like it has the same mark although not an ideal comparison. I also think the bill colouration does change with different angles, in some views the bill looks yellow/dusky yellow where at other angles especially with closer views, the dark mandibular unguis is quite obvious. I still think we are dealing with one bird and a combination of asymitry in bill colouration and a trick of the light may be at play but given the short time between my two sets of photos and not being able to confirm the neck smudge when viewing the bird from the right I can’t rule out the possibility of two birds. Does anyone know if the mandibular unguis is in plane with the rest of the bill? Im just wondering if it is tilted in or tilted out would this lead to the mandibular unguis looking dark at some angles and concolourous with the rest of the bill at other angles? cheers, Rob