Adaptation of Bird Communities to Farmland Abandonment in a Mountain Landscape

Abstract

Widespread farmland abandonment has led to significant landscape transformations of many European mountain areas. These semi-natural multi-habitat landscapes are important reservoirs of biodiversity and their abandonment has important conservation implications. In multi-habitat landscapes the adaptation of communities depends on the differential affinity of the species to the available habitats. We use nested species-area relationships (SAR) to model species richness patterns of bird communities across scales in a mountain landscape, in NW Portugal. We compare the performance of the classic-SAR and the countryside-SAR (i.e. multi-habitat) models at the landscape scale, and compare species similarity decay (SSD) at the regional scale. We find a considerable overlap of bird communities in the different land-uses (farmland, shrubland and oak forest) at the landscape scale. Analysis of the classic and countryside SAR show that specialist species are strongly related to their favourite habitat. Farmland and shrubland have higher regional SSD compared to oak forests. However, this is due to the opportunistic use of farmlands by generalist birds. Forest specialists display significant regional turnover in oak forest. Overall, the countryside-SAR model had a better fit to the data showing that habitat composition determines species richness across scales. Finally, we use the countryside-SAR model to forecast bird diversity under four scenarios of land-use change. Farmland abandonment scenarios show little impact on bird diversity as the model predicts that the complete loss of farmland is less dramatic, in terms of species diversity loss, than the disappearance of native Galicio-Portuguese oak forest. The affinities of species to non-preferred habitats suggest that bird communities can adapt to land-use changes derived from farmland abandonment. Based on model predictions we argue that rewilding may be a suitable management option for many European mountain areas.

Rural abandoned landscapes and bird assemblages: winners and losers in the rewilding of a marginal mountain area (NW Spain)

“…Recent studies have presented rewilding as an alternative option for land use in cases of farmland abandonment (Guilherme and Pereira 2013;Navarro and Pereira 2012;Queiroz 2013). The trends in land abandonment could also be seen as an opportunity rather than a threat, even though the conservation of traditional farming systems is also associated with biodiversity and cultural value (Navarro and Pereira 2012).…”

“…Several authors have recently suggested that rewilding 1 may be an appealing conservation response to farmland abandonment in areas of Europe and the rest of the world where the social structure of farming communities has been eroded and low-intensity farming is no longer socially or economically viable (Navarro and Pereira 2012;Guilherme and Pereira 2013;Queiroz et al 2014). These authors propose rewilding as a potential alternative approach to conservation, in which the maintenance costs are much lower than the current target-driven, intensively managed approaches (Gillson et al 2011;Navarro and Pereira 2012;Queiroz et al 2014).…”

“…Land abandonment and fire are complex and closely interrelated processes, and their spatial interaction strongly determines vegetation patterns and biodiversity at different spatial scales (Le Viol et al 2012;Navarro and Pereira 2012;Guilherme and Pereira 2013). While land abandonment favours mature forest species, it simultaneously favours and threatens early-successional species because vegetation maturation may lead to increases or lost of shrubland habitat depending on the initial vegetation characteristics.…”

Rewilding European Landscapes

“…Species diversity patterns in traditional landscapes are likely to be different from what would be found in non-modified (primary) landscapes (Blondel and Aronson 1999). When the total number of species is considered, a higher richness of species at the habitat patch scale (i.e., α-diversity) is expected in traditional landscapes due to species being able to use more than one habitat and due to the high density of habitat edg-es, which facilitates inter-patch movements and therefore leads to a higher species turnover in space and time (Proença and Pereira 2013;Guilherme and Pereira 2013). Note that even with inter-patch movements, each habitat type will support a distinct community of species due to differences in species abundances and due to the existence of strict habitat specialists.…”

Understanding Bird Preference on Agroforestry System: Is There a Potential Case for Birdwatching Development?

“…As much as 60% of bird species with various ecosystem role lives on the agroforestry area [9]. Moreover, there is an interesting tendency in which the birds prefer to live on the transition region between farmland and primary forest as illustrated by agroforestry, compared to other area, such as monoculture forest and active farmland [10,11].…”