http://www.birdguides.com/webzine/article.asp?a=2188
Important bit is: We are appealing to all sea-watchers to keep a close eye on any Manx Shearwaters they see, and report any sightings of colour-marked birds to SeaWatch SW (http://www.seawatch-sw.org/contact.html).
We are not releasing details of the colours used, or the extent of the marking, as we don't want to bias the results. However, we request that observers note the following details:
Date, time and location
General weather/viewing conditions
Direction of flight and distance from watchpoint
Number of Manx Shearwaters in group
Colour and extent of marking (be as accurate as possible)
Observer name and email/phone number
This Shearwater is actually a juvenile that has lost its fluffy feathers.