When you see birds roost... do not disturb
BALMY summer days when the wild calls of Sandwich Terns jar against the simmering horizon off Ainsdale beach seem as distant as the terns themselves are now.
Writing this in December, with a chill draught seeping through the window seal and rain sluicing down the pane, it is easy to figure out why our summer visitors undertake perilous journeys to warmer wintering grounds.
Many of these spectacular birds, which spend July and August roosting on the sands at Ainsdale, will have made the journey south to Senegal and Gambia in western Africa by now, with some even flying as far away as Namibia for an easier life, and more abundant supplies of food.
The contrasts between the blinding sun of Africa and its high temperatures, and the Stygian blackness and buffeting winds of an Ainsdale evening in winter were obvious when I met with volunteers to discuss the results of our third annual survey of the terns recently.
Thanks to our dedicated team of volunteers, 26 counts were made of the roost in July and August, with the team concentrating on the periods over high tide.
They also recorded the types of disturbance the birds suffered, for unfortunately there are still folk who don’t see a problem with flushing these birds and the thousands of waders that seek refuge on our coastline during migration periods.
It is imperative that all human visitors give these birds a wide berth when they are trying to rest on a journey that most of us would struggle to complete, especially as their roost sites lie within the Sefton coast Site of Special Scientific Interest.
One of the reasons the Sefton coast enjoys the protection of international law is the large numbers of migrating birds that stop off here.
Many human visitors, unaware of the damage their actions can cause to these roosts, are mortified when they learn how the birds quickly become exhausted if forced into the air when they should be resting and conserving energy.
This year our counters recorded a total of 4,040 Sandwich Terns in the roost at Ainsdale, compared to 9,945 birds in 2017, but the number of scaly young birds was up from 102 in 2017 to 257 this year.
The maximum daily count this year was of 840 birds, well down on the peak of 1,500 the year before, which was also down on the summer of 2016, when 2,734 were counted on one volunteer visit.
Why do numbers appear to be falling?
Disturbance is certainly a factor, with dog walkers, horse riders, kite surfers, walkers and photographers all recorded disturbing the roosts this year, and the number of disturbance incidents were up on previous years.
Fluctuations in food supply offshore may also have an effect on the number of birds, as could weather conditions.
This year’s count is still much higher than records from as recently as 2012, when the Ainsdale roost amounted to just over 300 birds.
Hopefully next year’s counts will add a further piece to the tern jigsaw puzzle, but with the balmy summer days a way off yet, all that remains is to sincerely thanks all our volunteers who took part in this year’s survey.
We hope to see you (and the terns) all again next year…
Above, the terns rise from the Ainsdale roost against a stormy sky
Left, three Sandwich Terns – including a ringed bird on the leftBelow left, volunteers count the Sandwich Tern roost at Ainsdale