NIAB - National Institute of Agricultural Botany

Orson's Oracle

Reversing the decline

Posted on 28/12/2011 by Jim Orson

There was a very thoughtful reply to my blog on the impact of predators on the numbers of farmland birds including two key statements: ‘the predators have as much right to exist as their prey’; and ‘….controlling a species to benefit another is just wrong. It's manipulating nature, not conservation’.

I have sympathy with these statements, but there remains the need to reverse the slide in farmland bird numbers in order to meet one of Defra’s quality of life indicators.

Since the baseline year of 1970 there has been a fall of over 50% in farmland bird numbers. Over the same period populations of magpies and sparrowhawks nearly doubled.

Now, I’m not saying that this is by any means a cause and effect. However, the increase in predator numbers must have had some influence on farmland birds. Is it really fair to ask for a return to the numbers of farmland birds recorded in 1970 when there were significantly fewer predators?

The response referred to earlier also stated ‘the fact that they [predators] are still doing well is because actually there is plenty of prey out there on our farms for them to flourish’. I suppose the tongue-in-cheek response must be perhaps we should be using predator numbers as the indicator rather than the population of farmland birds?

There is no doubt that much of the decline in farmland birds has been due to changes in land use. The reduction in mixed cropping and the increase in winter crops at the expense of spring crops have been major factors. We’ve seen publically-funded schemes try to reverse these declines, but they don’t seem to have worked.

Research by the University of Reading has concluded that take-up of ELS options is very much out-of-line with the requirements of farmland birds. There needs to be more clarity on which options are required in order that declines can be reversed.

But this clarity will bring some unpalatable news to some farmers. There will be a need to devote land to wildbird seed mixes for winter food and for flowers for insects in the summer. These in-field options have not been popular, but really are the essence of trying to get a balance between biodiversity and food production.

The Government is examining future options under ELS and also has consulted on new quality of life indicators. Previous experience and research like the University of Reading’s hopefully mean that we not only get realistic and pragmatic indicators but also the means of achieving them.

I say pragmatic partly because I have to ask why we cannot currently use pesticides or fertilisers to optimise the biodiversity gain from the hopefully limited area we have to devote to this aim.

Reducing the area needed will have wide support from farmers. It’s not these inputs that have been directly responsible for the decline in biodiversity, but they could in the future make a significant contribution to reversing it.

blog comments powered by Disqus