THIS is the time of year when birdwatchers will be clutching their binoculars with added fervour.
They will be looking to the skies or scouring the surface of every water body in anticipation of seeing something out of the ordinary.
The reason for this activity is that birds will begin arriving from the south in large numbers as the summer migration gets under way bringing everything from swallows to cuckoos to our shores.
Literally millions of birds will cross the English Channel and take up their summer residence here in the UK.
Some will only stay in the south, others will journey to the far north.
Wherever they go, these birds seem to arrive out of nowhere.
Just as the winter migrants prepare to migrate back to where they came from - bewick’s swan, purple sandpiper, fieldfare and brambling - they are set to be replaced by the summer alternatives.
The summer migrants are coming here to breed, of course, and to feast on the plethora of insects and other summer food available here.
It is a fine annual extravaganza for nature lovers and we can all enjoy the presence of these warm weather visitors in our lives.
There will be chiffchaffs and willow warblers in our woodlands, house martins and swallows around our fields and waterways, swifts screeching over our houses.
You might even be lucky enough to hear a nightingale or see a nightjar flutter around at dusk or dawn.
The interest in summer migrant birds from ornithologists means that long-term records of their arrival dates have been amassed.
Local bird reports and national data from organisations such as the British Trust for Ornithology show that the various species don’t all arrive at once but that from March onwards there is wave after wave of feathered invaders.
In recent years, there have been records ofmigrants arriving earlier.
Climate change is real and is having an effect.
Species such as blackcap have been overwintering in Britain in ever increasing numbers for decades but this year there has been a record of a swallow staying through the cold months.
The reason being that it hasn’t been that cold overall.
But ofcourse insect eaters like that are vulnerable if the weather should change for the worse.
The records show that one of the earliest arrivals at the beginning of March is the sand martin.
This is a browner version of the more well-known house martin which nests in holes next to water.
They usually start to be seen in the first half of March, as do the wading bird the little ringed plover and the wheatear.
As March progresses, more species usually arrive, such as the elegant osprey, swallow, house martin, yellow wagtail, willow warbler and the chiffchaff.
But it is in April that the big influx usually begins, weather willing. Bad rain or strong winds can delay this immigration in a big way.
Early in April, the UK can expect the likes of the garganey (a duck), hobby, common and arctic tern, cuckoo, tree pipit, ring ouzel (like a blackbird but with a light breast), grasshopper warbler, sedge warbler, and whitethroat.
From mid-April, there will be black tern, nightingale, lesser whitethroat, garden warbler and pied flycatcher.
The are some species which come a little later in May such as wood sandpiper, nightjar and spotted flycatcher.
Of course, don’t hold these dates as sacrosanct.
Nature has its own calendar and birds can arrive earlier or later than these dates.
There is some overlap with the birds which have wintered here, especially in March and April.
Bewick’s swan and whooper swan usually fly off in mid-March, closely followed by whitefronted goose towards the end of the month.
Other waterfowl like scaup, long-tailed duck and velvet scoter could hang around until May.
The better-known fieldfare and redwing - two thrush species from Scandinavia which come over here to feast on our berries - will tend to leave in April, though there are occasional records of them breeding here.
There are always cases at this time of year of unusual species turning up.
They may have been blown off course by winds or just got lost.
Some, however, turn up in small numbers each year. Examples include the hoopoe, beeeater, golden oriole, white stork and corncrake.
Some breed here in small numbers on a regular basis and with the change in climate may well set up annual breeding populations, which would be quite exciting to all those twitchers out there.
Birds can turn up anywhere but if you want to increase your chances of seeing something unusual, you could check out well-known rarity spotting sites such as Gibralter Point or Spurn Point on the East Coast. Birds pass through these as they travel north.
All you need to spot birds is a pair of binoculars, a notebook (to write down what you see and make notes on species you can’t initially identify) and perhaps a field guide of all the birds likely to be seen in this country. There are a great many of these, some better than others.
So, spring and summer are great times to be a birdwatcher and it is far nicer wandering around looking for species when it’s warm than it is in the bleak midwinter.
Even for non-birdwatchers, the influx of species can be a joy. Perhaps you are lucky enough to have house martins nesting under the eaves of your home (alas less likely these days) or swallows using your farm outbuildings?
You may seen swallows, house martins or sand martins fluttering over areas of water or along rivers.
I have seen sand martins along the River Don in the middle of Rotherham.
Some migrants are less common than they used to be. It is now getting rarer and rarer to hear a cuckoo, and a nightingale is a definite rarity.
You certainly won’t hear one in Berkeley Square!
Look to the skies to see the new birds flying about and open up your ears to hear the new songs as our feathered friends swap Africa, Asia and the continent for the good life of Britain.
They are certainly welcome visitors.