The importance of altitude and aspect for breeding WhinchatsSaxicola rubetrain the uplands: limitations of the uplands as a refuge for a declining, formerly widespread species?

Evidence for contrasting causes of population change in two closely related, sympatric breeding species the WhinchatSaxicola rubetraand StonechatSaxicola torquatain Britain

“…migrant and earlier breeding species allows it to benefit from milder winters and springs by exploiting emerging climate niches (Jiguet et al 2009, Zollinger 2011. If anything, the climate niche of Whinchat in hillside grassland mosaics may be being squeezed (Calladine & Bray 2012).…”

“…Late period abundance change among Whinchats was not significantly associated with any land cover LCM2000 variable, bar a negative association with IG and CON (all tree-age categories combined; Table 2). Although some young growth stage conifer plantations will have supported Whinchats (Bibby et al 1985, Calladine & Bray 2012, appropriate data on woodland age classes were not available and hence the over-riding observation is for avoidance of forests. For Stonechat, there was a negative association (more Table 1.…”

Breeding success affects site fidelity in a WhinchatSaxicola rubetrapopulation in abandoned fields

“…First, the majority of Whinchats in Western Europe breed in agricultural grasslands -wet meadows, hayfields, and pastures (Bastian et al 1997). Accordingly, agriculture intensification appears to be the main factor affecting their breeding success, mainly due to early mowing of grasslands and the associated nest destruction (Müller et al 2005, Grüebler et al 2008, Broyer 2009, Broyer et al 2012, Calladine & Bray 2012, Fischer et al 2013. Secondly, the existing studies on demographic parameters of Whinchats in Western Europe were carried out in declining populations with low breeding densities (Müller et al 2005, Grüebler et al 2008.…”

Nestling diet optimization and condition in relation to prey attributes and breeding patch size in a patch-resident insectivorous passerine: an optimal continuum and habitat constraints

“…Indirectly, given the colonization success and overall increase in populations of the Whinchat in abandoned farmland areas, this suggests that progressive climate change (mostly shortages of rainfall and reductions in temperature) are not disadvantageous for this species [e.g. in the Scottish Highlands Whinchats preferred warmer south-facing hillsides (Calladine and Bray 2012)]. One can assume that the major threats to Whinchats and other birds breeding in grasslands nowadays are the direct mortality/ nest losses of birds due to mowing and the intensification of agricultural management as a result of the encroachment of tall grass species resulting from nitrogen deposition and acidification, which diminish habitat suitability and reduce prey accessibility Broyer et al 2014;Fischer et al 2013;van Oosten et al 2014).…”