The main migration period in Britain takes place between mid-April and mid-May. This is the time when migration peaks for many of the birds that come here to breed during the summer months, and when those birds that breed at more northerly latitudes head off north. At this time lots of birds just use Britain as a refuelling stop, whilst some also arrive here by mistake, having been blown off course by south-easterly winds.
So, whilst the main event is slowing, the golden hour is upon us.
Late May/early June is the time when some of the most exciting birds can and often do turn up here. The last couple of days saw the winds that most birdwatchers dream of in late spring - those magical south-easterlies - and they didn’t disappoint. Red-footed falcons began to arrive, with four individuals being seen at Spurn Point, East Yorkshire, on Sunday alone, and a handful of others at other sites too. Right now Red-footed falcons are making their way from east Africa to the asian grasslands and bogs a long way from the British east coast, so these birds are being ‘drifted’ east by those intoxicating winds.
Of course these aren’t the only eastern migrants to get caught-up in this weather pattern. Several marsh warblers that are heading to north-eastern and eastern Europe have been found too, along with a couple of black kites and at least one black stork. But it’s not just about drift migrants. For a few species, late May and early June is the time that they migrate, and right now we are seeing the arrival of quails and nightjars in Britain. Both are amongst the last of our summer visitors to arrive here.
Whilst most of our swallows and swifts, warblers and flycatchers will have already arrived and will be settled in their chosen breeding territories, getting on with the arduous task of raising a family, some will still be on the move and on a visit to the coast you will almost certainly see some of these still migrating. These might just be tardy individuals but are more likely those that breed much further north, in Iceland, or around the Arctic Circle.
It makes sense for these birds to migrate late, as getting there too early could result in disaster; their breeding areas may well still be covered in snow, with insects thin on the ground or non-existent. So, what weather conditions are we looking for? Ideally south-easterly airflow and a bit of rainfall during the hours of darkness – many of our migrant birds move at night and rainfall brings them down to land. Warm southerly winds from the Sahara will also bring birds with them.