The conservationists’ dilemma

One of the more contested parts of the RSPB’s work revolves around predation and particularly those native predators that eat birds.

It is, however, a fact of life that all bird species are subject to predation.  Predators have lived alongside most of their current natural bird prey for thousands of years without eliminating them. However, bird populations can decline or their numbers can be held low where levels of predation on them are high.

The reality is that predators are loathed by some and loved by others.  Our view is simple – native predators are part of the rich variety of life as worthy of conservation as any other species.  I would go further: a key test of whether we are living sustainably is whether we are able to coexist with predators.

Emotions spill over in debates about fish-eating birds such as cormorants and goosander or when birds of prey are perceived to conflict with commercial shooting interests (such as buzzards on pheasants or hen harrier on grouse).

The conservationists’ dilemma comes when science shows that predation is a contributory factor to the decline of already threatened species. 

In 2007, we compiled a review of the impacts of predators on wild birds.  We looked at the peer-reviewed published literature and drew some conclusions. 

“The review concludes that generalist ground predators, such as foxes, can sometimes reduce the population levels of their prey, and that this is a growing worry if we are to conserve populations of threatened ground-nesting birds, for example lapwings. This conclusion accords with the RSPB’s considerable practical experience as a land manager of over 130,000 hectares in the UK. The review also concludes that the evidence to implicate predators such as sparrowhawks in the declines of songbirds is very weak.”

We have recently undertaken a follow up review which we shall publish in due course.  But I can reveal that the results of this review (looking at the scientific literature since 2007) broadly reinforce these conclusions. The review also raises some interesting questions around the ultimate drivers of “predation problems”. In many cases, it appears there are other factors which if addressed, could remove or greatly reduce the predation effect. But more to come on this later in the year...

Where evidence suggests that predation is causing a problem for species of conservation concern, the RSPB’s strong preference remains to concentrate on habitat measures that favour the prey species and make life more difficult for the predator. For example, where lapwing productivity and numbers on our nature reserves are poor, we concentrate first on improving the habitat for lapwings (usually supported by agri-environment schemes) and on creating physical barriers such as electric fences to limit fox access. Sometimes the stakes are so high for ground nesting birds that there is no alternative to predator control – it is always a last resort.

Twenty-first century conservation requires us to look at both proximate and ultimate causes of decline. That is why we reject any strategy that fixates on control of native predators as the silver bullet.  For some species (such as songbirds) it will be a red-herring, for others it might need to be part of the solution, but on its own it will never be enough.  In many ways, the impact of predation is a symptom of a broken environment, tackling the symptom doesn’t cure the disease but it does buy vital time.

Tomorrow I shall report on new research on lapwings which will give pointers to how policy and research should evolve to help address the conservationists’ dilemma.  

What do you think about our position on predators?

It would be great to hear your views.