Nyon Lakeside, on a cold and windy day.
It's always very hard to approach birds, especially when you've got a big lens that makes you look very strange. I usually walk very slowly to the area that they are in, and just crouch down and wait for them to come back after a few minutes they'll get used to your presence.
Canon EOS 500, Sigma 70-200 f/2.8 EX HSM, Fujichrome Sensia 100 ISO