Unlike in Spring there is no sense of urgency and the birds can and often do remain for a few days, even longer sometimes, as the pressing urge to get to the Arctic for the short window of opportunity that will allow them to pair, nest and raise young is now forgotten until next year. The birds can enjoy, if that is the right word, a less frantic spell in their lives as the late summer days provide an opportunity to rest and replenish, restoring energy levels in preparation for the tougher winter months to come.
The first returning waders are usually adults, still in breeding plumage. A plumage that shows distinct signs of wear. It is the failed adult breeders that return first, followed by the females, for with waders it is generally the rule that the females leave the males to tend to the young on the breeding areas and a little later they too will follow the females south.
Today there were two adult Dunlin and an adult Turnstone pattering along the water's edge picking tiny morsels from the concrete.Like many waders here they showed little alarm at a human presence and one could virtually walk up to them.
Turnstones are regular passage migrants at the reservoir, being seen singly or less often in small groups. By the time they show up on their return migration at the reservoir they have already travelled a great distance, anywhere from Greenland, northeast Canada and Siberia, possibly other points nearer in Fennoscandia too. I have no idea where the Turnstones that visit here in late summer are bound for. It could be only as far as the south or east coasts of Britain, where a number spend the winter or maybe further to southern European shores, even the coasts of West Africa or down as far as South Africa but it is always nice to see them, especially in their rich tortoiseshell breeding colours. Soon enough they will moult into a drab brown the colours of the rocks and seaweed they haunt in winter.
The two Dunlin accompanied the Turnstone. Although still in breeding plumage their feathers had lost the immaculate perfection of pre-breeding and were frayed and worn, the upperpart feathers in particular, giving the two Dunlin a distinctly threadbare appearance. Like the Turnstone they will commence a moult into dull grey upperparts and white underparts that is the sum of their winter plumage.
Dunlins are comprised of up to eleven races but only three are likely to occur at Farmoor. The differences between these three races are subtle, involving size, bill length and tiny plumage variations and it is often impossible to differentiate any individual concerned, especially when in transit at the reservoir.
The two most likely races to occur are Calidris alpina alpina and C.a.schinzii.
C.a.alpina breeds in Fennoscandia and across western Siberia and individuals from as far east as the White Sea and the Yamal Peninsula in northwest Russia spend the winter in Britain and Ireland. This is the most likely to occur at Farmoor.
C.a.schinzii breeds mainly in Iceland and southeast Greenland with a small number even breeding in northern Britain, Ireland and southern Norway. They winter in West Africa. I can think of only one instance when I was almost certain I had seen one at Farmoor and this was only because I could see it was so much smaller (a characteristic of schinzii) than the other three Dunlin (presumably alpina) with which it was associating.
The third race that might occur at the reservoir but is unlikely is C.a. arctica which breeds in northeast Greenland and could arrive on passage as it makes its way to wintering areas in West Africa.
I am as guilty as anyone of falling into the trap of granting the Dunlins only a superficial glance due to their relatively regular presence on passage at Farmoor but stop and linger and look at them as their tiny forms scuttle along by the water, stopping to cock an enquiring head and look you in the eye before carrying on feeding. They too, like the less usual and more sought after wader species that can arrive at Farmoor, have travelled phenomenal distances, bringing with them to the prosaic surrounds of an unremarkable inland reservoir, the romance of far distant lands and the sheer wonder of bird migration.
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