More agroforestry … to support bird diversity!

• Bird species richness (the number of different bird species) in agroforestry systems was more than twice as high as in open agriculture, and similar to the diversity found in forests and orchards. This may be explained by the higher habitat heterogeneity of agroforestry systems, forests and orchards compared to open agricultural land. Trees are highly valuable habitat for birds; for nesting, finding shelter, and feeding.

• Bird community composition differed between habitat types and between European regions. Temperate agroforestry systems hosted fewer bird species than Mediterranean agroforestry (but still more than the open field in both areas), mainly generalist and woody-habitat species. The higher agricultural intensity in north-western Europe, leading to a sharper decline in bird diversity, could explain why we recorded fewer bird species here. For example, in England (Wakelyns), no birds were recorded at all in the open fields, while 7 different bird species were recorded across the three sampled agroforestry fields (Common whitethroat Curruca communis, European robin Erithacus rubecula, Great tit Parus major, Common pheasant Phasianus colchicus, Willow warbler Phylloscopus trochilus, Eurasian magpie Pica pica and Eurasian wren Troglodytes troglodytes). In the Mediterranean, where agricultural systems are less intensive than in temperate regions, bird communities in agroforestry systems were composed of species from both open and woody habitats, and thus these systems represent an important habitat for birds relying on semi-open conditions.

In summary, we show that agroforestry systems both in temperate regions and in the Mediterranean represent highly valuable habitats for birds. Their wider implementation across Europe could thus play an important role in halting and reversing the decline of bird diversity in European farmland.

In a nutshell: If you are motivated to implement agroforestry on your land, it is likely to have a positive effect on bird diversity since trees and other woody elements are important for bird diversity, especially in ecosystems where they have become scarce – such as in our modern agricultural landscapes. Agroforestry systems, which reintroduce farmland heterogeneity, can provide a compromise between production demands and nature conservation needs. They should certainly be considered as an option to combat the global biodiversity crisis! And finally, if we take a step, or a flight, back we should not forget that landscape diversity is the key for more biodiversity!