Conservation gains cost £4.80/ha a year – GCT
By Louise Impey
CONSERVATION practices introduced to support gamebird shoots have wide-ranging benefits for other wildlife, according to 10 years of research by the Game Conservancy Trust.
But those benefits come at a cost, which growers need help with if they are to achieve biodiversity goals, says senior GCT ecologist Dr Chris Stoate.
Techniques used on the GCT Allerton Projects 330ha Loddington Estate demo-farm in Leicestershire have boosted numbers of songbirds, small mammals, butterflies and insects, with songbird numbers showing the greatest rise, reaching 1970s levels in just three years, says Dr Stoate.
But the methods used (see panel) have a cost. "Conservation management needs financial support. If farmers are to deliver biodiversity, then there will have to be more financial incentives for environmental management," he says.
Over the 10-year period conservation costs totalled £15,884 or £48/ha, notes Allerton project manager, Alastair Leake. And conflicts have arisen. "Permanent set-aside strips breaking up fields mean you create two new headlands, with their associated yield loss."
Establishing crops by the Loddington "green method" costs £177/ha, compared with just £15/ha with a "scorched earth" approach, he adds. "And there is a loss of work efficiency with small fields and a very diverse cropping pattern."
Now research at Loddington is to focus on in-crop issues. "There has been a lot of greening the edges. Now we want to take things further," says Mr Leake. "Things like row widths can be very important to wildlife habitats and may allow in-crop hoeing." *
Research lessons from Loddington
• Big wildlife benefits, but cost £4.80/ha a year.
• Field margins – 2m strips of tussocky perennial grasses such as cocksfoot, timothy and fescue; 6m strips of finer grasses for more open sward and easier cutting. Flowers encouraged for nectar production to support insect populations.
• Set-aside strips (20m) through middle of fields, each with a beetle bank, kale-based mixes providing winter bird food, cereal-based mixes supporting invertebrates and aiding weed control. Sunflowers only attract greenfinches and deplete very quickly. Triticale holds grain longer.
• Beetle banks established by ploughing and planted with tussocky grasses boost aphid control up to 80m into crop. Huge increase in harvest mice – 50 nests/km compared with five nests/km in set-aside.