Effekter av predationsrisk på sånglärkors (Alauda arvensis) habitatval på åkermark
Along with other European farmland birds, the skylark (Alauda arvensis) has declined rapidly since the 1970’s. Between 1975 and 2003, the Swedish population of skylarks declined with 64 %. In Britain, the decline is often explained by alterations in farming practices in general and the shift from sp...
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ftsluppsalast:oai:stud.epsilon.slu.se:1768 2023-05-15T13:10:03+02:00 Effekter av predationsrisk på sånglärkors (Alauda arvensis) habitatval på åkermark Ehlin, Johanna 2010-09-07 application/pdf https://stud.epsilon.slu.se/1768/1/ehlin_j_100907.pdf swe swe https://stud.epsilon.slu.se/1768/ urn:nbn:se:slu:epsilon-8-703 https://stud.epsilon.slu.se/1768/1/ehlin_j_100907.pdf Ehlin, Johanna, 2010. Effekter av predationsrisk på sånglärkors (Alauda arvensis) habitatval på åkermark . First cycle, G2E. Uppsala: (NL, NJ) > Dept. of Ecology <https://stud.epsilon.slu.se/view/divisions/OID-415.html> Agriculture - General aspects Animal ecology Nature conservation and land resources First cycle, G2E NonPeerReviewed 2010 ftsluppsalast 2022-09-10T18:08:45Z Along with other European farmland birds, the skylark (Alauda arvensis) has declined rapidly since the 1970’s. Between 1975 and 2003, the Swedish population of skylarks declined with 64 %. In Britain, the decline is often explained by alterations in farming practices in general and the shift from spring-sown to winter-sown cereals in particular. The dense vegetation structure of winter cereals is limiting the number of breeding attempts possible, causing the entire population to decline. In Sweden, however, the proportion of winter-sown cereals has remained stable and cannot be held responsible for the decline. Furthermore, Swedish skylarks do not perform as many breeding attempts as their British relatives and the popu-lation is therefore not as dependant on opportunities to rebreed. On the contrary, the dense structure of winter cereals could benefit Swedish skylarks since it offers slightly more pro-tection from predators. Given the high proportion of presumably predator-friendly forest edges bordering arable fields in Sweden, it is likely that any possibility to nest closer to forest edges would be beneficial for the skylark, since it would make larger areas avail¬able as habitat. In this study it is examined how the habitat preferences of Swedish skylarks are af-fected by winter- and spring-sown cereals in fields where adjacent forest edges causes pre-dation risks to increase. Information on the distribution of singing skylarks in fields sown with winter wheat, spring-barley and oats has been analyzed using a General Linear Mixed Model (GLMM) in order to investigate how territory densities are affected by the three way-interactions between the date of the inventory, the sowing-time and the presence of forest edge adjacent to the field. Results show that territory densities in winter-sown cereals decline significantly during the season. In spring-sown cereals, densities increase significantly in fields adjacent to forests and remain stable on fields with no forest edge. Thus, skylarks seem to prefer fields ... Text Alauda arvensis Swedish University of Agricultural Sciences: Epsilon Archive for Student Projects Åkermark ENVELOPE(20.717,20.717,65.767,65.767) |
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Open Polar |
collection |
Swedish University of Agricultural Sciences: Epsilon Archive for Student Projects |
op_collection_id |
ftsluppsalast |
language |
Swedish |
topic |
Agriculture - General aspects Animal ecology Nature conservation and land resources |
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Agriculture - General aspects Animal ecology Nature conservation and land resources Ehlin, Johanna Effekter av predationsrisk på sånglärkors (Alauda arvensis) habitatval på åkermark |
topic_facet |
Agriculture - General aspects Animal ecology Nature conservation and land resources |
description |
Along with other European farmland birds, the skylark (Alauda arvensis) has declined rapidly since the 1970’s. Between 1975 and 2003, the Swedish population of skylarks declined with 64 %. In Britain, the decline is often explained by alterations in farming practices in general and the shift from spring-sown to winter-sown cereals in particular. The dense vegetation structure of winter cereals is limiting the number of breeding attempts possible, causing the entire population to decline. In Sweden, however, the proportion of winter-sown cereals has remained stable and cannot be held responsible for the decline. Furthermore, Swedish skylarks do not perform as many breeding attempts as their British relatives and the popu-lation is therefore not as dependant on opportunities to rebreed. On the contrary, the dense structure of winter cereals could benefit Swedish skylarks since it offers slightly more pro-tection from predators. Given the high proportion of presumably predator-friendly forest edges bordering arable fields in Sweden, it is likely that any possibility to nest closer to forest edges would be beneficial for the skylark, since it would make larger areas avail¬able as habitat. In this study it is examined how the habitat preferences of Swedish skylarks are af-fected by winter- and spring-sown cereals in fields where adjacent forest edges causes pre-dation risks to increase. Information on the distribution of singing skylarks in fields sown with winter wheat, spring-barley and oats has been analyzed using a General Linear Mixed Model (GLMM) in order to investigate how territory densities are affected by the three way-interactions between the date of the inventory, the sowing-time and the presence of forest edge adjacent to the field. Results show that territory densities in winter-sown cereals decline significantly during the season. In spring-sown cereals, densities increase significantly in fields adjacent to forests and remain stable on fields with no forest edge. Thus, skylarks seem to prefer fields ... |
format |
Text |
author |
Ehlin, Johanna |
author_facet |
Ehlin, Johanna |
author_sort |
Ehlin, Johanna |
title |
Effekter av predationsrisk på sånglärkors (Alauda arvensis) habitatval på åkermark |
title_short |
Effekter av predationsrisk på sånglärkors (Alauda arvensis) habitatval på åkermark |
title_full |
Effekter av predationsrisk på sånglärkors (Alauda arvensis) habitatval på åkermark |
title_fullStr |
Effekter av predationsrisk på sånglärkors (Alauda arvensis) habitatval på åkermark |
title_full_unstemmed |
Effekter av predationsrisk på sånglärkors (Alauda arvensis) habitatval på åkermark |
title_sort |
effekter av predationsrisk på sånglärkors (alauda arvensis) habitatval på åkermark |
publishDate |
2010 |
url |
https://stud.epsilon.slu.se/1768/1/ehlin_j_100907.pdf |
long_lat |
ENVELOPE(20.717,20.717,65.767,65.767) |
geographic |
Åkermark |
geographic_facet |
Åkermark |
genre |
Alauda arvensis |
genre_facet |
Alauda arvensis |
op_relation |
https://stud.epsilon.slu.se/1768/ urn:nbn:se:slu:epsilon-8-703 https://stud.epsilon.slu.se/1768/1/ehlin_j_100907.pdf Ehlin, Johanna, 2010. Effekter av predationsrisk på sånglärkors (Alauda arvensis) habitatval på åkermark . First cycle, G2E. Uppsala: (NL, NJ) > Dept. of Ecology <https://stud.epsilon.slu.se/view/divisions/OID-415.html> |
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1766212751606153216 |