What is this bird similar to a seagull but with a forked swift-like tail? I observed these birds in Saint Petersburg, Russia this June, mainly in the evening when the sun was setting. They are similar to seagulls and often fly (presumably hunting) at the same location as the seagulls. Easily noticeable differences from seagulls are: 1. Forked tail, like swifts have 2. Narrower wings, which seem longer 3. Higher-pitched short tweets, which never turn into "laughter". A sample (with car noise in background) can be heard here. Here are some photos I could took. They are blurred and chromatically aberrated because it's hard to focus with a telephoto lens and such fast motion towards and away from me. I exposure-compensated them to make the colors visible, so the photos are a bit noisy. I hope they are useful for identification anyway. ![]( ![]( ![]( ![](

This is one of the numerous species of tern. They are common birds of the seashore and rivers world-wide. The characteristic forked tail and the black cap on the head is what gives it away.

It is hard to say for sure given the chromatic aberration altering the colours, but this is likely to be either from the genus _Sterna_ (particularly the Arctic tern or the common tern), or possibly the little tern ( _Sternula hirundo_ ).