Impact of grassland farming intensification on the breeding ecology of an indicator insectivorous passerine, the Whinchat Saxicola rubetra: Lessons for overall Alpine meadowland management

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

“…In our study population the average distance of a flight from the nest by parent Whinchats was 33 m [±SD 21.2 m, range 4-80 m (Frankiewicz 2008)]. This value was smaller compared with previous data for Whinchats foraging in extensive grasslands in Sweden [43.8 m (Andersson 1981)] or Alpine meadows in Switzerland [42.2-54.7 m (Britschgi et al 2006)]. Moreover, pairs of Whinchats breeding in narrow, long-abandoned fields often foraged in adjacent crop fields (mostly oil-seed rape, but avoiding winter cereals) compared to pairs breeding in large patches of non-cropped vegetation (Frankiewicz 2010).…”

“…It may be that parent birds compensate for the negative impacts of a deteriorating environment (i.e. a smaller breeding patch area) by working harder to get the same or reduced amount of food for their young, thereby maintaining a standard reproductive output (Brickle et al 2000;Morris et al 2001;Britschgi et al 2006); our previous investigation in this study area did not provide any evidence that the area of abandoned fields where the Whinchats bred affected their breeding success or productivity (Frankiewicz 2010). We found evidence that Whinchat broods from larger patches of non-cropped vegetation received more sedentary and heavier prey such as Orthoptera, Araneae and soildwelling invertebrates (such as Diplopoda/Mollusca).…”

“…The primary breeding habitat of Whinchat used to be invertebrate-rich grasslands, especially those lying within traditionally managed agricultural landscapes, where the abundance and diversity of arthropod prey were higher than in intensively managed grasslands (Oppermann 1999;Bastian and Bastian 1996;Britschgi et al 2006;Broyer et al 2012;Strebel et al 2015). The recent population decline of grassland birds, including the Whinchat, has been ascribed mainly to nest losses/female mortality resulting from more intensive agriculture practices, primarily earlier and more frequent mowing (Grüebler et al 2008(Grüebler et al , 2012, deteriorating food/foraging conditions in semi-natural grasslands/meadows and the loss of marginal habitats (Müller et al 2005;Britschgi et al 2006;Perlut et al 2008;Broyer 2009;Broyer et al 2012Broyer et al , 2014Henderson et al 2014;Strebel et al 2015). A very recent investigation has found evidence that mortality in Whinchats occurs primarily outside the wintering period, i.e.…”

“…Therefore, the diet of Whinchats may differ substantially between grasslands and abandoned farmland. Hitherto, all dietary studies of nestling Whinchats were restricted to different grassland types (reviews in Bastian and Bastian 1996;Suter 1988;Britschgi et al 2006), with hardly any detailed dietary data for Whinchats (and other bird species) breeding in abandoned farmland. Importantly, however, owing to the progressive increase in the acreage of abandoned farmland in some temperate areas of the northern hemisphere (Kamp et al 2015), such knowledge is essential in order to diagnose the biodiversity and viability of bird populations in this habitat (Kamp et al 2015;Tryjanowski et al 2009;Sanderson et al 2013;Plieninger et al 2014;Zakkak et al 2015).…”

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?

“…In many areas it is now confined to upland meadows, where grass cutting dates have not advanced as a result of agricultural intensification (Müller et al 2005, Bolliger et al 2007, Broyer 2009), and also abandoned or derelict agricultural land provides extensive areas of uncut grassland (Frankiewicz 2008, Orowski 2010. Increased nest losses and greater mortality of incubating females attributable to the earlier cutting of meadows (Gruebler et al 2008) and reduced food availability (Britschgi et al 2006) have been identified as causal mechanisms produced by agricultural intensification that have lead to population declines and range contractions of Whinchats. As a trans-Saharan migrant, factors away from the breeding areas could also have contributed to their decline (Sanderson et al 2006).…”