Habitat Creation and Measurement
The Rawcliffe Bridge biodiversity initiatives introduced have been practical and have already proved valuable to fellow farmers during numerous farm walks and training days held by the farmer James Hinchliffe in partnership with BASF.
Independent annual counts of birds (conducted to RSPB and British Trust for Ornithology standards), bats, moths and butterflies have also been undertaken to gauge the effectiveness of the measures.
These counts have been very valuable in planning what needs to be done next to encourage the species that you want on the farm.
The focus has been on enhancing the wildlife features on the farm using simple techniques, farm labour and standard farm equipment. BASF have worked with James Hinchliffe to establish year-round food supplies for birds as well as roosting/nesting sites James has planted and encouraged plant species which have in turn attracted amphibians and insects, particularly those species fed to fledglings during the nesting season.
Pollinators also benefit from the managed approach to creating habitats. Butterflies and bees respond to an increase in pollen and nectar in the landscape which attracts pollinators and helps increase populations.
The mixture of flowering species within the habitats created using “biodiversity by design” are situated ideally within the farm to encourage foraging. Pollen and nectar are produced from early spring to late autumn by planning sowing dates and bee nest sites are found in the field ditch sides and woodland. Similarly, butterflies benefit from the tall grassy habitat enhanced with a variety of wild flowers which, together with nearby woodland, deliver areas for hibernation and egg laying.
Simple approaches implemented from the early years include:
- The feeding of ‘tail corn’ or screenings harvested from the headlands in the yard and on farm tracks over the winter;
- Putting up 30 nest boxes in 2003 for hole-nesting birds like tits and tree sparrows. By 2011, a total of just over 100 nesting boxes significantly boosted blue tit, great tit and especially tree sparrow numbers, the latter have established a new colony in farm woodland;
- Putting up barn owl nesting boxes at the edge of established woodland and along hunting flight lines;
- Supplementary feeding is routine during winter: feeders are placed adjacent to woodland;
- No use of summer insecticides for aphid control in winter wheat for the past 12 years;
- Direct cutting of oilseed rape instead of swathing which delays disturbing the field for 10-14 days giving the resident reed buntings time to fledge their last brood of young;
- Ditch and dyke management to encourage water voles to recolonise.
Nearly every field has a ditch around two sides, which provide good wildlife corridors and the annual dredging and cutting is delayed until October on a rotational rather than annual basis to encourage the tussocky grasses favoured by voles. Mr Hinchliffe has also planted 7 acres of native broad-leaved trees and berry-bearing shrubs with Corsican pine, alongside a 100-year-old oak wood. To extend the wildlife corridors further grassy margins have been planted.
Wild bird mixes and cover crops
Planting a mix of plant species in field margins is the best way of providing a good range of wild bird food and cover throughout the seasons, but to take our understanding further, BASF started working with Limagrain UK (then Advanta Seeds) to better understand what bird species fed on which wild bird cover crops and when.
Seasonal drilling sequences have been undertaken since 2005 at Rawcliffe Bridge testing over 30 individual wild bird food crops. This work has been extended to The Grange since autumn 2008 to test performance in a different soil type.
The trials are extremely practical; it’s about looking at what food can be provided in the different seasons and then looking at the seed rates, drilling dates and the establishment of different wild bird food crops. They also include herbicide interaction trials to determine which herbicides could be used to help control the pernicious arable weeds which often out-compete wild bird and cover crops during the first season of establishment.
Crop structure is also investigated in the trials.
The results show some marked differences in the lifespan of individual plant species, an important consideration given the costs associated with establishing field margins and cover crops.
The aim is to have some feed and cover value from crops over the different seasons and then to add in some flowering species to encourage insects on which the birds can then feed. Then it’s about putting mixes together that attract the birds you want to encourage.
The work conducted allowed Limagrain to develop a mixture of vetch, triticale, Phacelia, fodder radish and linseed which can be sown in the autumn.
The species combination has compatible plant structure which doesn’t compete with itself, but most importantly, provides food for birds at different times of the year.
The benefit of sowing a mix in the autumn is that it gets established in better soil conditions in October and then when spring comes, which is when the breeding cycle for birds is starting; there is already an established habitat with flowers to encourage insects for feeding fledglings and to provide a very useful area to attract and encourage bees.
Biodiversity statistics at Rawcliffe Bridge
Rawcliffe Bridge is a 350-acre intensive arable farm near Goole in East Yorkshire.
Since the biodiversity work was started by farmer James Hinchliffe in conjunction with BASF in 2002, the practices have achieved the following:
- 110 bird species, above average for a lowland farm and including 64 species on the list for conservation concern;
- 25 skylark territories, which is nearly 2 times the UK average lowland density;
- Tree sparrow numbers increased from 6 to 59 pairs between 2003-2010 following the introduction of ‘bed and breakfast’ nest boxes and feeding stations;
- Corn bunting numbers are 3 times the UK lowland average;
- Grey partridge numbers are 6 times the UK lowland average;
- Meadow pipit territories around the field boundaries are over 2.5 times the UK lowland average;
- Yellow wagtail territories are 47 times the UK lowland average;
- Successful breeding between 2004-2010 for kestrels, tawny owls and little owls;
- 154 plant species on field boundaries;
- 165 species of moths, 22 species of butterflies, 8 species of dragonflies and 2 species of bats identified to date;
- 56 species of water plants surveyed, including 5 rare species;
- Good water quality evidenced by common stonewort, dragonflies, damselflies and sticklebacks.