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Bracken, Fintan
Preferred name
Bracken, Fintan
Official Name
Bracken, Fintan
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Now showing 1 - 2 of 2
- PublicationBreeding bird species diversity across gradients of land use from forest to agriculture in Europe(Wiley, 2018-08)
; ; ; ; ; Loss, fragmentation and decreasing quality of habitats have been proposed as major threats to biodiversity world-wide, but relatively little is known about biodiversity responses to multiple pressures, particularly at very large spatial scales. We evaluated the relative contributions of four landscape variables (habitat cover, diversity, fragmentation and productivity) in determining different components of avian diversity across Europe. We sampled breeding birds in multiple 1-km2landscapes, from high forest cover to intensive agricultural land, in eight countries during 2001-2002. We predicted that the total diversity would peak at intermediate levels of forest cover and fragmentation, and respond positively to increasing habitat diversity and productivity; forest and open-habitat specialists would show threshold conditions along gradients of forest cover and fragmentation, and respond positively to increasing habitat diversity and productivity; resident species would be more strongly impacted by forest cover and fragmentation than migratory species; and generalists and urban species would show weak responses. Measures of total diversity did not peak at intermediate levels of forest cover or fragmentation. Rarefaction-standardized species richness decreased marginally and linearly with increasing forest cover and increased non-linearly with productivity, whereas all measures increased linearly with increasing fragmentation and landscape diversity. Forest and open-habitat specialists responded approximately linearly to forest cover and also weakly to habitat diversity, fragmentation and productivity. Generalists and urban species responded weakly to the landscape variables, but some groups responded non-linearly to productivity and marginally to habitat diversity. Resident species were not consistently more sensitive than migratory species to any of the landscape variables. These findings are relevant to landscapes with relatively long histories of human land-use, and they highlight that habitat loss, fragmentation and habitat-type diversity must all be considered in land-use planning and landscape modeling of avian communities.433Scopus© Citations 5 - PublicationEffects of set-aside management on birds breeding in lowland IrelandFarmland birds have suffered a severe decline in recent years throughout Europe including Ireland. Agricultural intensification is believed to be the main cause and this has led to the introduction of agri-environmental schemes, of which set-aside is a part. Bird abundance and diversity were compared between set-aside and adjacent tillage or grassland at 18 locations. The set-aside sites were also assigned to one of four management types: rotational set-aside, non-rotational set-aside, first year set-aside that was productive grassland in the previous year, and long-term set-aside that was grazed by animals in winter. Species diversity and the abundances of skylark, meadow pipit and woodpigeon were significantly greater in set-aside sites. Species diversity was not significantly different between set-aside management types and meadow pipit, skylark, pheasant, house sparrow, magpie, snipe and starling were closely associated with non-rotational set-aside, which also contained significantly larger numbers of these species compared to the other set-aside types. This study shows that set-aside does enhance bird diversity and abundance and that, in Ireland, the most effective form of set-aside is non-rotational. It also shows that the most appropriate form of set-aside will vary from situation to situation and that a one size fits all view should not be taken in the development of agri-environmental schemes.
965Scopus© Citations 27