Back when I wrote this article during autumn, Turtle Doves were passing through nearby at La Janda, near Facinas. I saw scores of them drifting over sunflower fields only to hear the distant sound of gunshot and come to the sickening realisation that this species was the hunters’ quarry.
Some of these birds may well have been travelling from their breeding grounds in the UK, where their population has decreased by over 96% since the 1970s and continues to half every seven years.
Titan, the 2014-16 satellite-tagged Turtle Dove was a superstar; the first UK-breeding Turtle Dove that was followed on its entire migratory journey from his breeding grounds in Suffolk to Mali and back again – and back to Mali a second time.
One of his satellite-tagged brethren came into the news for a much more galling reason though, when it was legally shot in Spain and handed in to the authorities near Córdoba.
But this yearly slaughter is only one of the challenges this bird faces, and not even the one driving its precipitous decline.
Food shortages on breeding grounds
Research carried out in England shows that the loss of suitable habitat on the UK breeding grounds and the associated food shortages for Turtle Doves is the single most important factor driving the species declines.
Turtle Doves now produce less than half as many chicks as they did in the 1970s. Back then they would attempt up to three broods a year, whereas now they take so long to regain fitness after their migratory journey that there is barely time for one.
Unlike other dove and pigeon species in the UK, turtle doves are obligate granivores – their diet is formed exclusively of seeds. The lack of available summer seeds in the countryside is associated with this alarming reduction in nesting attempts. This one factor alone is sufficient to explain the current rates of decline.
Disease
An emerging potential additive cause of population decline is the disease Trichomoniasis, perhaps best known for its recent deleterious effects on Greenfinches. Recent research has highlighted a high prevalence of infection in Turtle Doves by the parasite that causes this disease.
Unsurprisingly, Turtle Doves that are under increasing food stress must be more susceptible to the disease, the symptoms of which are lesions in the mouth and throat which prevent the bird from feeding, and ultimately cause it to starve to death.
One potential disease vector is the Pheasant, 40 million of which are released every year in England alone with no environmental risk assessment. As food-stressed Turtle Doves share seed and water sources with these birds, the opportunities for infection become greater.
Unsustainable levels of hunting on migration
Of the estimated population of 3-6 million pairs of Turtle Dove breeding in Europe and Russia, the annual hunting bag total in EU member states alone was estimated at 2-3 million birds, although it is important to note that these figures are from the EU Turtle Dove Management Plan published in 2007.
If these figures are accurate estimates, hunting may constitute a significant factor driving population declines in an already stressed population. As brood production diminishes due to the factors identified (summer seed source) the species can no longer sustain hunting pressure to this level.
Habitat loss on wintering grounds
Africa’s farming landscape is changing. Important wetlands (a key feature for Turtle Doves) are being drained for irrigation of crops, and Sahelian scrub removed for intensive agricultural production of salad crops and other produce exported to Europe.
On the wintering grounds, Turtle Doves roost communally in Acacia thickets, seeking sites that are safe from predators and disturbance. As trees are being lost from the landscape, these safe roosting sites are become fewer. With birds gathering in large compressed numbers, hunting here will now also represent a more significant threat, particularly with an increasing number of European hunters visiting the region on “sporting trips”.
As well as direct mortality from gunshot, the resulting disturbance causes a functional loss of the habitat as a safe roosting site.
The future
The future for the species does indeed look bleak. Despite the efforts and passion of individual conservationists, the larger conservation organisations have shown little drive, direction or urgency, leading to a rather lethargic approach to the issue.
In important migration areas such as La Janda, the species should be afforded a degree of protection until the full impact of hunting can be ascertained or until numbers have recovered. The hunting community has not had a great track record with set regulation so the update to the EU Turtle Dove Management Plan should include measures to legally protect the species on migration.
Additionally – and perhaps most importantly – there needs to be a wholesale change in the way we view our countryside in Europe. Sustainable management needs to be put at the heart of farming polices, and market-led initiatives should be encouraged and incentivised to deliver landscape-scale habitats across networks for Turtle Doves and other species.
In doing so that will give you and I as consumers the opportunity to buy Nature-friendly produce that supports farmers and land managers doing the right things for nature!
Author: Simon Tonkin, Inglorious Bustards
Photos: Peter Jones
Note: The views expressed in articles are those of the authors, and are not necessarily those of the Society.