Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2017

Erindi/veggspjald / Talk/poster E11

Agriculture and breeding waders in lowland Iceland

Höfundar / Authors: Lilja Jóhannesdóttir (1), Jennifer A. Gill (2), José A. Alves (1,3), Sigmundur H. Brink (4), Ólafur Arnalds (4) & Tómas Grétar Gunnarsson (1)

Starfsvettvangur / Affiliations: 1. University of Iceland, 2. University of East Anglia, UK , 3. University of Aveiro, Portugal, 4. The Agricultural University of Iceland

Kynnir / Presenter: Lilja Jóhannesdóttir

The capacity of different landscapes to sustain viable populations depends on the spatial and temporal availability of key population-specific resources within those landscapes. Heterogeneous landscapes generally sustain higher levels of biodiversity than homogenous ones as those provide a wider range of resources. Agricultural expansion has resulted in large-scale homogenisation of landscapes with associated declines in many taxa. However, during the early stages of agricultural development, increased landscape heterogeneity and changes in local productivity through fertilizer inputs can potentially increase resource availability for some species. Agriculture in Iceland is not yet highly intensive or extensive, and primarily occurs as hayfields embedded within a mosaic of semi-natural wetlands and heaths. These landscapes also support internationally important breeding populations of several wader species but the role of agricultural land in promoting or constraining breeding waders densities is currently unknown. Understanding the effect of agriculture land on these wader populations is important as the area of cultivated land is likely to expand in Iceland during the coming years, in big part through conversion of the remaining wetlands. Here we quantify the relationships between breeding wader densities in lowland Iceland and the amount of cultivated land in the surrounding landscape, in order to assess the extent to which cultivated land affects wader populations in these landscapes, and the potential implications on wader density of future expansion of cultivated land at the expense of wetlands. Densities of waders on transects through wetlands were greater in landscapes with larger amounts of wetland, indicating the importance of more wetland availability for these species. The amount of cultivated land in the surrounding landscape interacts with altitude, as wader numbers decline with increasing amounts of cultivated land at lower latitudes but the inverse pattern occurs at higher latitudes, suggesting that the additional resources provided by cultivated land may be more important in the less fertile uplands. Further conversion of wetlands into cultivated land in low-lying areas of Iceland is likely to be detrimental for breeding waders, but such effects may be reduced or even reversed in less fertile areas.