If only Adam had waited another day or two to write his blog.... This afternoon we've had a green winged teal on back Saltholme pool, and very visible from the Saltholme pools hide. This is a North American variant of the much more commonly seen Eurasian teal and the difference is subtle, so here's a link to the Sibley Guides website to guide you through the differences. http://www.sibleyguides.com/2011/03/distinguishing-green-winged-and-common-teal/ Happy birding!