12th April: Noah's Lake Terns

Two Terns spent most of this afternoon feeding on Noah's Lake, the first Terns of the year on the Avalon Marshes. They were either Common or Arctic Terns, these two are very similar and particularly difficult to separate, and are often referred to  as 'Commic Terns'. The birds today were typically tricky, as they were very distant at the back of the lake, and always into the sun. Identification is hampered in Spring as the dark 'wedge' on the upperwing of Common Tern which is usually such a useful identification feature is not apparent, as it is created when the fresh silvery grey edges to the feathers wear away over the course of the year to reveal darker feathers.

I managed a few very distant photos of the Noah's birds. I am fairly confident that they are Arctic Terns, but would be very happy to hear any other opinions (or similar opinions for that matter!).

The following features led me to think Arctic:

• Short bill, not the relatively droopy elongated bill of Common
• Fairly even translucency to the flight feathers. On Common Tern, the inner primaries are much more translucent than the outer primaries
• Long, thin, well-defined black trailing edge to primaries
• Long tail streamers
• Grey belly and breast contrasting with white cheek patch

Also nice to see was one of the colour-ringed Great White Egrets, the same bird that features in the header photo of this website.

If any sharp-eyed readers noticed, the reason that the rings are on opposite legs to the bird in the header photo is that I 'flipped' that photo to make it fit the title text.