Sand Martin (Riparia riparia)
This once common bird in Europe has declined in recent years due to drought in it’s wintering ground of Africa. It is one of the earliest arrivals to the UK, sometimes arriving in early March. It feeds on insects which it often catches in flight over water. It nests in burrows which it digs in sandy banks. It lays 4 -
They fly very fast so you will need a solid tripod with a fast Gimbal type head. We used the Manfrotto 393 Gimbal head with a 500mm prime lens and switched between the 1.4 and 1.7 teleconverter. They were only static for a very very brief number of seconds so the speed of the auto focus is very important. Hence the mix of tele converters. The bird is very small so the 1.7 was better for fine detail although the auto focus was slower.