A song thrush celebrates the ending of the afternoon rain with repeated trills, scales and whistles. In the trees either side of the footpath, other birds join in the wall of bird song – warbling dunnocks, tinkling goldfinches and stuttering chaffinches. Greenfinches add their harsh falling notes. Groups of midges hover above the woodland track. It’s the first time I’ve seen the flies in these numbers; another sign that plentiful food is emerging in time for the birds’ breeding season.

I reach the Hanger viewpoint overlooking the brooks that line the River Arun. Wigeon quietly whistle and wander among the pools in the fading light. Excitable lapwing flap and loop above them, calling “pee-woot”, but even they are settling down now as evening approaches.

A bright pink spot flashes above the brambles in the gloom. A handsome male bullfinch, with a velvet black cap and bright pink chest and underparts, is plucking hungrily at the remains of berries. There’s a soft mush of chewed food gathering along the edge of his beak as he eats. Below him, a duller black, brown and soft pink female is also feeding hurriedly.

It’s remarkable to see these thick-set finches, so conspicuous now, and think that this is a relatively rare treat, especially in spring and summer. Occasionally, while driving along the lanes, you may see a black and white tail disappear into the roadside hedge, but they’re nervous birds that prefer to remain hidden in dense vegetation, only giving away their presence with a soft, plaintive whistle. Although common in Sussex – their population here is static – bullfinches have been declining in south-east England, possibly from a loss of the dense, mixed vegetation they prefer.

The low sun emerges briefly from the cloud, and the bullfinches’ moist black beaks glisten.

I hear splashing in the brooks below, and look down to watch a small herd of dark brown fallow deer run out across the flooded grass. They upset a pair of shoveler ducks, which fly up and in turn disturb two irritated lapwing. It’s only then that I notice the young peregrine falcon, perched in a tall tree, also watching.

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