Rich riverside growth and thickets, flowering banks and blossom attracting a diversity of insects welcome the exhausted migrants, providing warmth, shelter and plentiful food after a cold and hazardous journey.
The previous post showed how the wildflowers on the riverside all appeared at once, this post will be describing how the migrant birds reached our riverside at last.
Sunday 12th May was sunny with a breezy start - Listen!
Blackbirds were singing in their usual trees together with a song thrush. Many starlings were about, to and fro, clearly busy raising young somewhere. Robins were singing still or collecting food for young. An unusual song came from deep inside the blossom-faded Blackthorn - and Hawthorn, this now dense with new leaves. What was singing? It was still singing over an hour later - a warbler, almost certainly a reed warbler perhaps attracted by the new pond created alongside the river over the past year.
Looking up, small clouds were scudding past on a south west wind and with them, a fine hobby - zig-zagging in a typical hunting flight over the river until it was out of sight.
Where were the swifts?. The insects attracting the hobby were heralding rain - the cloud thickened and , in the last of the sun, the swifts appeared at last quite high over the river, the first seen here this year! Above them, even higher soared a buzzard. House martins have only been seen in ones and twos, also very late. Perhaps this is just as well as had these migrants, the swifts, swallows and martins arrived earlier they would have found no insects to feed on. There have been reports of migrant birds arriving on our shores in a weak and starving state, finding insufficient food en route.
Monday 6th May was clear, sunny, a very slight breeze in places with abundant wild flowers now clothing the once bare river banks. Trees were coming into leaf, leaves replacing blossom on the Blackthorn in some places but in others the blossom still dominated. Signs of blossom were appearing amongst the fresh green Hawthorn leaves. Nature has arranged the perfect timing of the two 'companion' trees, Blackthorn providing the earliest blossom for early bees then, when that is blown away, Hawthorn takes over, providing a continuous foraging source.
THE DAWN CHORUS! A slight diversion here, back to the early hours:
Waking at 4.30 am most mornings as it started to become light - with most of Sussex sleeping, opening the window, a sound so unworldly wafts along the river, waves of voices, some near and some far all combining to form the river dawn chorus.
The sound is more like an infinite choir with each bird singing its own song but, being birdsong, the combined song is full of harmonies, with no notes clashing or out of tune, it is sound in landscape, now soft, now loud, not static in space. Nearby blackbirds, robins and song thrushes can be singled out but the more distant the voices, the more strange it becomes, a blanket of song with thousands of voices, like mist along the valley, disappearing too in wisps like mist at sunrise.
MIGRANT WARBLERS and others
At 09.15 on 6th May many birds were singing all along the river, the dawn chorus long since ended, each bird was busy - too busy to maintain continuous song. It was a clear sunny morning with no wind just a slight breeze.
In shady patches, Bluebells and Lesser Celandine were still flowering with signs of Hawthorn Blossom appearing amongst the fresh green leaves. Oaks and Ash were also coming into leaf at last and the wheat crop in the fields was growing fast.
Buttercup (Ranunculas)
attracts insects to the damp meadow grass
A good number of Warblers were now active in the river bank willows and blossoming Hawthorn, with singing willow warblers (3) and chiffchaffs (11) in various stages of nest preparation, making the most of the fine calm weather. Blackcaps (8) were catching up with nesting, all having arrived on the riverside in a 'fall' of migrant birds. Some males singing loudly, one right at the top of a tree, pausing now and again to fly out and catch an insect then back to perch and resume its variable and beautiful song, another was singing a soft subsong whilst others uttering a 'chink' deep in the undergrowth were certainly nesting. One or two had been bathing down on the river and were drying their feathers in the sun.
From three adjacent riverbank willows came songs from three warblers and a wren. This time the warblers were garden warblers (3), inconspicuous birds which confusingly are not usually seen in gardens but prefer habitat such as this with dense low cover from where they sing a fast musical
and long-lasting song. Further along the river in an area of long grasses near the edge of one of the new ponds came the mixed song of fast chattering and musical notes of a sedge warbler (2), which also prefers dense tangled vegetation - and damp nettlebeds and ditches - hence it's name. Another bird was heard on the other bank of the pond. Good news as the new ponds and their vegetation should increase the diversity of habitats in the area.
Common Whitethroats (by no means common!) (10) were enjoying the drier areas on the river bank, singing their scratchy song and searching out nest sites. Here again these warblers prefer scrambled scrub, nettles, bramble patches and tangled riverside undergrowth in which to hide and today some were singing from the dense and leafy Blackthorn thickets and flying across to survey other areas, singing at each perch. More birds were joining in the song, no longer just a trio or quartet but more of a large choir, two from the willows, three from a bramble patch and more from the Blackthorn.
Local birds, the wrens have been singing for a long while now and have well established territories low on the banks but they have to continue to advertise their presence by first singing form low down, then moving upwards so that their loud song can be heard all along the river. Today they were easy to count, 16 at least, each guarding their own patch.
Other Resident birds ('sedentary' doesn't do them justice) - were very active too, with blue tits (27) and great tits (15) calling and foraging in their own territories, blackbirds (23) were present in good numbers, some foraging on the muddy river edges and others singing loudly from prominent perches.
It was good to hear song thrushes (4) out-singing the blackbirds although far less numerous.
Robins (13) too were singing, giving sudden loud bursts of song very close by. Dunnock (4) were much less conspicuous, one flew across into a blossom filled tree, another was lurking under the nettle stems on the bank and two were busy foraging low down under tree roots. Up higher in a tree, making its way along a horizontal oak branch over the river was a treecreeper, with another glimpsed nearby, possibly a pair, foraging.
House sparrows (36) were busy in the Brambles, Blackthorn thickets and blossoming Hawthorn, hard to see but their chattering gave them away. More were bathing in the river and flying up to dry off, leaving a female mallard dabbling close to where they established a nest last year.
Goldfinches (5), some singing in the undergrowth were seen in small numbers, the winter flocks having split up now, whilst chaffinches (6) were all visible and singing with greenfinches (6) calling from high perches in nearby trees, the males showing off their brilliant spring green plumage....
and the Hawthorn blossom has suddenly appeared, attracting bees,
as the Blackthorn blossom has blown away.
The sun had brought out the butterflies, with a fine Peacock butterfly seen basking on the river bank on dry warm nettle stalks then flying off and returning to the same spot to resume basking. The value of last years nettle stalks cannot be underestimated! They form a platform which quickly dries out and warms up for freshly emerged butterflies - and form cover for small mammals, nesting places, nest materials for birds and hiding places for unfledged juveniles. Other butterflies seen were a Comma, basking on river bank nettles, a Green-veined White on the long grasses, a Small Tortoiseshell butterfly flying low over the river bank grasses and nettles, a Holly Blue butterfly around an ivy clump, two Speckled Wood butterflies over a shady bank - and - by far the most numerous, Orange Tip butterflies chasing over the wild flowers on the meadow grass and Cuckooflower along the river bank (at least 20 males with the characteristic orange wing tips and less easily identified white females). Bumblebees (white-tailed and red-tailed) and many smaller flying insects ranged the riverside flowers and blossom.
A sudden loud warning yaffle from a green woodpecker in an old tree meant there was danger overhead. The anxious cry came from a nesting green woodpecker - but what was the cause of the alarm? Looking up, there, skimming the treetops, circling around and returning, was a kestrel, its head down, focusing on the trees and river under its flight path.
The kestrel disappeared, leaving the sky to herring gulls (23) gliding on the warm thermals, a single magpie, several small groups of starlings (31), and 2 buzzards, probably a pair, and lastly a fine song in the sky, high up, came from a skylark, hardly visible.
