Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2023

Effects of wetland patch size on bird numbers and density

Höfundar / Authors: Aron Alexander Þorvarðarson (1), Tómas Grétar Gunnarsson (2), Gunnar Þór Hallgrímsson (1), Aldís Erna Pálsdóttir (2)

Starfsvettvangur / Affiliations: 1. Háskóli Íslands, 2. Rannsóknasetur Háskóla Íslands á Suðurlandi

Kynnir / Presenter: Aron Alexander Þorvarðarson

Wetlands are critical as feeding and breeding grounds for many bird species but are under great anthropogenic pressure globally. Wetlands larger than 2 ha are legally protected in Iceland indicating that smaller wetlands might be less important than larger ones. However, little is known about the relationship between wetland patch size and density or biodiversity. To address how wetland patch size affects birdlife, bird counts were performed during the spring and early summer months of 2021 and 2022 in 113 wetland patches in south and west Iceland, ranging from 0.05 to 27 hectares in size.
Preliminary findings suggest that as wetland patches grow larger, the total number of birds within patches increase, which highlights the ecological importance of larger wetlands for birds. However, bird density tended to rise as wetland patches became smaller. The latter trend might be of great ecological and conservational importance and highlights the complexity of avian ecology and the importance of small wetland patches which have no legal protection in Iceland.
The preliminary key findings challenge conventional assumptions about avian habitats in Icelandic wetlands and contribute to a larger debate on the importance of habitat patch size. The findings also underscore the need for data-driven strategies to guide wetland management and bird conservation.