The effects of predator control on breeding moorland birds

Key points

  • Lapwing, golden plover, curlew, red grouse and meadow pipit bred on average three times more successfully when predator control was performed.
  • As a result, the populations increased in subsequent years.
  • In the absence of predator control, the populations declined.

Background

Lapwing callingControl of generalist predators such as foxes and crows is commonly performed to protect livestock and game birds, but its potential to contribute to conservation of other wildlife is not well understood. Birds that nest on the ground such as curlew, lapwing and golden plover are particularly vulnerable to predation, and long-term fox and crow populations increases in recent decades may have increased predation pressure.

What they did

Fletcher and colleagues ran an experiment for eight years to look at the effects of controlling predators on five species of ground-nesting birds that breed on moorland. They included four different moorland sites, in two pairs. In one pair, one site received predator control for the whole experiment and the other did not. In the other pair, one site received predator control for four years and one did not, then the sites were swapped for the remaining four years of the experiment. On all four sites the numbers of breeding birds and estimates of breeding success were made.

This approach allowed them to compare how the birds did on the same piece of moorland when predator control was or was not happening. They could also compare between the two areas that did and did not receive predator control on the same year.

What they found

Predator control techniques reduced the abundance of foxes by 43% and crows by 78%, but no change was detected in already low stoat and weasel abundance.

Birds were monitored to see how many breeding pairs fledged young each year – this means that the pair successfully reared at least one of their chicks until it was able to fly.

For lapwing, golden plover and curlew, more than three times as many pairs fledged young when predators were controlled than when they were not. For meadow pipits, twice as many pairs fledged young.

Bird species   Birds fledging young when
predators were not controlled
  Birds fledging young when
predators were controlled
Lapwing   19%   57%
Golden plover   18%   75%
Curlew   15%   51%
Meadow pipit   28%   52%

 

During the period of predator control, there was an increase in breeding success that led to a significant increase in numbers of lapwing and golden plover the following year. As curlew take longer to mature to breeding age, a three-year lag period was allowed, and after this a similar positive response to predator control was detected. When predators were not controlled, the abundance of these species dropped – there were fewer birds each year than there had been the year before. The table below shows the size of these changes. They did not detect any effect of predator control on meadow pipit, skylark or snipe.

    Change per year
Bird species   Population trend when
predators not controlled
  Population trend when
predators controlled
Lapwing   36% decline   66% increase
Golden plover   29% decline   36% increase
Curlew   17% decline   14% increase

 

What does this mean?

In summary, when predators were controlled, lapwing, golden plover, curlew, meadow pipit and red grouse all bred better than on the same moorland when predators were not controlled. For lapwing, golden plover, curlew and red grouse this led to more birds breeding on the moor in subsequent years. Where habitat is favourable, the application of predator control may be important for conserving some ground-nesting bird species.

Read the original abstract

Fletcher, K.L., Aebischer, N.J., Baines, D., Foster, R., & Hoodless, A.N. (2010). Changes in breeding success and abundance of ground-nesting moorland birds in relation to the experimental deployment of legal predator control. Journal of Applied Ecology, 47: 263-272.

Will you help us stop curlew retreating?


CurlewWe don’t want the curlew to go the way of many of our much-loved birds, like the corncrake and the nightjar. They shouldn’t be consigned to a few remote places. That is why we are asking you to support this urgent appeal for funds.

Donate to the Curlew Appeal >

It is estimated that there are just 300 pairs south of Birmingham, and these could disappear in just eight years. However, this isn’t just a problem facing the south. Breeding curlew have declined by 46% across the UK in just 25 years. The picture would be more widespread if curlew were not thriving on driven grouse moors. 

Farmland conservation schemes have largely stabilised adult curlew numbers by halting further habitat loss.

The problem now is chick survival. The fate of the curlew is literally in the hands of farmers and gamekeepers - we need to get the right advice out there fast.

How you can help

£25 could help us to get our practical guidelines in the hands of those on the ground who can bring about curlew recovery

£100 could help us to highlight how current conservation policy is failing to give curlew the best chance of recovery by briefing journalists and politicians

£250 helps us to get advisors out to curlew sites and assess what can be done to aid their recovery on the ground this year

Donate to the Curlew Appeal >

Cookie Policy

Our website uses cookies to provide you with a better online experience. If you continue to use our site without changing your browser settings, we'll assume you are happy to receive cookies. Please read our cookie policy for more information.

Do not show this message again