Are farmsteads over-looked biodiversity hotspots in intensive agricultural ecosystems?

Abstract

Farmland biodiversity continues to decline because changes in modern agriculture have led to the degradation and loss of key habitats. One farmland habitat that has received little attention during development of conservation measures is farmsteads. We use bird count data from a survey conducted at over 600 sites in 3725km2 agricultural landscapes in southern Sweden to investigate the importance of farmsteads as potential sources of biodiversity in simplified landscapes. We found that farmsteads, on average, had more bird species and individuals than semi-natural pastures and infield infield non-crop islands, probably due to a larger area of non-field habitats at farmstead sites. Presence of farm animals was an important predictor of bird diversity and numbers at farmsteads while variables associated with arable land-use intensification had limited effect. Old farmsteads with no current active farming, on average, had low bird numbers. We found no effect of agricultural intensification at the landscape level on alpha diversity at farmstead sites. Rather, species richness and abundance of birds tended to increase as landscapes became characterized by more intensive agriculture with larger fields. Farmsteads are widespread in simplified agricultural landscapes and may provide habitat to a range of farmland species. Applying conservation measures to farmsteads and local surroundings that increase the availability of safe nest-sites and good foraging grounds for birds could be implemented through publicity driven schemes. This combined with other agri-environment schemes in the surrounding landscape could enhance the amount of critical resources for farmland birds.