Abstract
In 2015 we studied the relative importance of silage and cereal crops as breeding habitat for the skylark Alauda arvensis. In 2014 we had found that skylarks failed to breed successfully in grass silage fields. We compared skylark density between crops in one organic and one conventional farm, c. 100 ha each, at Kvismaren valley in south Sweden (approx. 59.2°N; 15.4°E). The densities were similar in all crops: 83 territories/km2 in silage and 75 (spring sown) or 80 (autumn sown) in cereal. However, silage harvest in early June and July destroyed, as in the previous year, almost all nests, effectively preventing skylarks from reproducing successfully in that habitat. Cereal fields are not harvested until after the young are fledged. Approximately 45% of the farmland area in Sweden is grass for silage, normally harvested in late May or early June. We suggest that this early harvest is an important and overlooked driver for population decline of birds nesting in such fields.
Highlights
The skylark Alauda arvensis is abundant all over Europe on intensively used farmland, natural pasture and coastal meadows
Conventional and organic farmland were compared in order to ind out whether there were any signiicant differences in population densities
Two large farms were chosen with similar location and ground conditions, essentially humus soil created by drained marshland
Summary
The skylark Alauda arvensis is abundant all over Europe on intensively used farmland, natural pasture and coastal meadows. It is the only passerine breeding directly on the ground in open ields away from scrub and tree which may be used as observation posts for predators. The causes are not fully known, but it is probable that there is a combination of factors behind the decline (BirdLife International). Intensive farming is a major threat, along with reduction of suitable habitat, and predation is a limiting factor. In England small mammals are major predators (Morris et al 2008, Buckingham et al 2015) whilst in other parts of Europe raptors and corvids predominate (Praus & Weidinger 2010)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
