The last month has been pretty busy for me out visiting farmers to give advice on various farmland bird matters including preparation of nesting areas for lapwings. We are lucky in Wiltshire that we still have widespread breeding lapwing.Through the Entry Level (ELS) and Higher Level Stewardship (HLS) Schemes, many farmers have chosen to provide fallow plots - areas of 1-2.5ha (2.5-5.5 acres) that they keep relatively clear of crops and vegetation throughout the breeding season. Birds will nest in maize and other spring sown crops but once the plants grow above their eye height and become dense the adults desert the area. The fallow plots allow the birds to make repeated attempts to breed which is denied to them in normal arable situations. It was thought that the plots would be able to able to provide the bird's food requirements also; they feed on bare ground or short vegetation foraging for surface and sub-surface invertebrates including earthworms, leather jackets and beetles.
Despite the numbers of these plots across the country, lapwing numbers are still in decline and a study of plots in Wiltshire last year showed a worrying lack of success for breeding birds. The scientific evidence suggest that a breeding pair only needs to produce 0.8 of a chick for numbers to remain constant so losses are expected and normal. The downward trend would suggest that birds aren't even managing this. So what is the problem? Researchers last year found birds nesting on fallow plots wandering some considerable distance away with their chicks and one explanation was they were looking for food. Following the observation of many birds on numerous plots it was suggested that the chicks were starving in addition to having to contend with predators. Last year's exceptionally dry weather would have exacerbated the problem.
Whilst pondering this I came across an excellent article by Henry Edmunds (HE) entitled "Lapwings on a Downland Farm" in February's British Wildlife magazine. He talks about lapwing on the family farm on the edge of Salisbury Plain from the 1920's to now and how their fortunes have changed as the farming system has modernised. The mixed farming system meant that birds nesting on spring barley fields (with tractors carefully driving around them) could "...take their newly hatched chicks to a neighbouring grass field, where they would be seen investigating cattle droppings or heaps of manure..." The most popular nesting areas were fallow fields which had either just had a stubble turnip crop (for livestock) or were to be cultivated over the coming months. HE recounts how one 32 acre field had 18 nests in 1972. The benefit of so many birds nesting in a relatively small area was strength in numbers; more birds can successfully defend themselves and their young against predators whilst a pair of lapwings is incredibly vulnerable.
In the mid 1970s farming systems were changing; grassland management became more intensive with increasing use of nitrogen over farmyard manure and mixed farming became less common as farmers specialised. Winter cropping increased, along with pesticide use and fallow became popular. It was no coincidence that farmland birds started declining in the late seventies. HE also talked about predators. In Victorian times foxes were so scarce on his farm that artificial earths were made and foxes introduced for the purpose of hunting. Fox numbers increased and around 20 a year were shot by the 3 gamekeepers employed on the farm until the late 60's, when numbers stared to escalate. At the same time gamekeeper numbers continued their decline which began at the turn of the century. Fast forward to 2007 when 120 lambs were killed by foxes on Henry Edmund's farm despite 150 foxes being shot that year. Crows and rooks are also a problem taking eggs and chicks.
Fallow plots were first introduced under Countryside Stewardship primarily for the rare stone curlew. The stone curlews' requirement for bare ground to nest on and its diet of soil-borne insects, both similar to lapwing, on paper anyway, suggested that these plots would be suitable for both species. The plots are now regularly recommended on farms where lapwing are seen as well as areas known to be favoured by stone curlew. Whilst the stone curlew have done very well in Wiltshire using these areas, lapwing are continuing to struggle. I have even heard reports of stone curlew adults eating lapwing chicks which was very unsettling (and hopefully pretty unusual).
HE has his own thoughts about plots and their suitability for lapwing...."in my experience lapwings are not generally successful upon them. The birds seem to feel insecure and will move their chicks away very soon after hatching, if they are not preyed on before. I have seen one lapwing move her family of four chicks three quarters of a mile over two days to get them from a stone curlew plot to a field of young kale."
One scientist with the Game and Wildlife Conservation Trust suggested that by creating these bare areas for lapwing to nest on are we inadvertently creating 'sinks' for them, areas where we encourage them to nest even though they might not be totally suitable (as the only available sparsely vegetated area on a farm) only to be targeted by predators? The size of the plots also limits the numbers of pairs that can use each plot; regulations now stipulate a maximum plot size of 2.5ha. This reduces the bird's ability to repel predators. Ideally plots are located adjacent to some semi-natural grassland so there is a good food source nearby but sadly on most farms this is not possible leaving the birds marooned in the middle of an arable desert. Do these plots provide sufficient food for the lapwing? Stone curlew seem to thrive on them so maybe food availability is not the issue and it is simply that the birds are too exposed and vulnerable to predation.
Is predator control the answer? Certainly farms with shoots and gamekeepers with zero tolerance for corvids and foxes seem to have better success with lapwing than those that don't. Electric fencing of plots during the incubation period also helps as this can deter badgers who are partial to newly laid lapwing and stone curlew eggs.
As with all ecological quandries there are many factors at play in the successful breeding of lapwing and many boxes need to be ticked in order for the birds to flourish. The research being carried out to assess what can be done to aid their breeding success will help inform our work with farmers and hopefully secure the future of such an iconic and beautiful bird.
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