The drastic decline of the turtle dove may have hit the headlines in recent weeks – but these photos show there are isolated pockets of Norfolk where this once-common bird still thrives.
Last month, the UK Breeding Bird Survey, undertaken by the RSPB, the Joint Nature Conservation Committee (JNCC) and the Thetford-based British Trust for Ornithology, showed a 93pc drop in turtle dove numbers between 1995 and 2014 – the largest decline of all species monitored.
Conservationists are working to arrest that decline by finding ways to encourage the right habitat and food sources for the birds.
But in a domestic garden near Dereham their numbers have risen from five to an estimated 14 birds in the last three years, which one wildlife campaigner says offers an insight into how the availability of food could be a key factor in the species' fortunes.
Wildlife photographer Chris Knights snapped these images from a hide – one capturing three pairs of the rare birds in the same frame, and another showing a juvenile turtle dove, an important record of one of this year's brood.
His friend and fellow conservation enthusiast Bill Makins, who founded the nature reserve at Pensthorpe in the 1980s, said the birds have all left the garden since these photos were taken last week, as the start of the harvest has given them a new food source before their migration in the autumn.
But he said it proves the value of supplementary feeding on a wider scale, and that turtle doves will return to food sources if it is made available in the sparsely-vegetated bare ground which they prefer to feed on.
'This is a back-yard garden, but the owner has been feeding these birds with sunflower hearts, wheat and millet since April,' he said. 'We know there are 14 birds, and that is all through supplementary feeding.
'I went to see the RSPB in Suffolk (near Walberswick) last year, and I realised that a lot of the strips that farmers are being advised to sow for turtle doves were not much good, because they were too tall. They are not flying into a tall crop. They like scrubby bare ground somewhere on the edge of a field.
'The type of feeding habitat they require is very difficult to create. But, clearly, if you feed them they don't need a very big area of ground at all.'
Rupert Masefield, communications officer for the RSPB in Eastern England, said the Operation Turtle Dove partnership is undertaking some scientific trials in Suffolk to assess the effectiveness – and safety – of supplementary feeding.
'One of the problems for turtle doves is disease and particularly this parasite called Trichomonas gallinae,' he said. 'Bird-feeding situations have been identified as breeding grounds for this parasite, which could facilitate the spread through the population. So there is a risk associated with supplementary feeding for turtle doves, and that is another issue the trial is trying to answer.
'The issue of seed plots that farmers put in as part of their stewardship agreements is something that has already been recognised. There was a PhD study that tested different management methods for these turtle dove food plants, and found that scarifying those plots to reduce the density of plants growing in them provides the open bare ground that turtle doves need to access the fallen food from these plants.
'This scarification method is now being recommended, within a mix of fumitory, black medick, red and white clover and vetch.
'It is a constant process of science to test the way of doing things, and see if it can be improved.'
Mr Masefield said people feeding seed to birds in their garden should ensure there is no excess seed on damp ground, and that feeders are kept clean and dry to reduce the risk of Trichomonas infections, which thrive in damp conditions.
To report a turtle dove sighting in a garden or farm, click here.
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