After a glorious summer of baking sunshine and a plentiful supply of insects to keep their bellies full, many of the Heart of England Forest’s summer visiting seasonal bird species are beginning to move on to warmer climes.
Fair weather visitors
Summer visitors to the UK, including swallows and martins, warblers, flycatchers, wheatears, redstarts, nightingales, yellow wagtails, tree pipits, swifts, nightjars and turtle doves arrive in spring to find breeding grounds that provide the insects to sustain them, along with suitable nesting sites.
A short-term visitor is the cuckoo. It is estimated that cuckoo numbers have declined by as much as 65% in recent decades, meaning that the chance of seeing or hearing these iconic birds is slim. Arriving in April or May, adult birds curtail their short visits to our shores in July, with their fully-fledged young following on soon afterwards.
While the warmer spring and summer seasons provide species such a swallows and swifts with the perfect environment to nest and rear their young, as the weather begins to cool and food supplies dwindle, so they are drawn to sunnier southern continents. Throughout September birdwatchers will see large gatherings of swifts and swallows beginning to congregate in readiness to make the long journey south, often punctuating their gruelling trip with stopovers in Southern Europe before continuing on to countries in Africa south of the forbidding Sahara desert. Amazingly, though, not all need a pit stop – the common swift holds the record for the longest continuous flight time of any bird, sometimes spending up to ten unbroken months in the air!
A question of timing
Birds of the same species do not always migrate together and a combination of the onset of shorter days, cooler weather and a reduction in food availability tell each bird when the time is right to leave. When their time has come, their behaviour starts to become more frantic, sometimes resulting in species flocking together pre-migration before some strike out alone while others prefer to travel en masse. If birds leave too early, they may run out of energy before finishing their journey. If they leave too late, they risk running into bad weather along the way.
Each species has its own schedule. House martins may hang around until October as they have to wait until their second – or even their third – brood has fledged, before the whole family heads south together. With many wading birds, the females set off first, leaving the males to stay behind and raise the chicks. The males leave as soon as the chicks can feed themselves, although many do not travel too far, preferring to spend the winter on the UK coast
Help us track those preparing to make tracks!
Although creatures of habit that often return to the same breeding grounds each year, occasionally species return later than anticipated. For example, observation by the BBC’s recent Springwatch programme estimated that some of Britain’s summertime swallow intake arrived between 30 and 60 days later this year than in previous years. Here at the Heart of England Forest we would love to hear from anyone who is out and about in the woodland and spots any would be migrant birds preparing to leave or even prolonging their stay deep into autumn – email us news of any sightings or photos on firstname.lastname@example.org and help us build up a picture of how long our summer visitors remain.