Konkurrensen mellan röding, sik och lake i Vättern : En djupdykning i tre konsumenters födopreferenser. Två tidsperioder: 1964-1978 samt 2006-2011
Lake Vättern contains Swedens most valuable population of arctic charr (Salvelinus umbla). The stock of this Salmonidae fish showed a negative trend for several decades but has now turned to a more positive one. Too minimize the risk of a new backlash it is important to obtain knowledge about the ar...
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Högskolan i Skövde, Institutionen för biovetenskap
2020
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ftskoevdehoeg:oai:DiVA.org:his-18066 2023-05-15T14:29:59+02:00 Konkurrensen mellan röding, sik och lake i Vättern : En djupdykning i tre konsumenters födopreferenser. Två tidsperioder: 1964-1978 samt 2006-2011 Interspecific competition between arctic charr, whitefish and burbot in lake vättern : Analyzing data from two periods: 1964-1978 and 2006-2011 Norén, Oskar 2020 application/pdf http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-18066 swe swe Högskolan i Skövde, Institutionen för biovetenskap http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-18066 info:eu-repo/semantics/openAccess Ecology Ekologi Student thesis info:eu-repo/semantics/bachelorThesis text 2020 ftskoevdehoeg 2022-10-25T20:51:56Z Lake Vättern contains Swedens most valuable population of arctic charr (Salvelinus umbla). The stock of this Salmonidae fish showed a negative trend for several decades but has now turned to a more positive one. Too minimize the risk of a new backlash it is important to obtain knowledge about the arctic charr and its interaction with other species. The purpose of this paper is to investigate the interspecific competition between arctic charr and two other valuable species i.e. whitefish (Coregonus maraena) and burbot (Lota lota). Data of stomach contents from two periods (1964-1978 & 2006-2011) were analyzed. The consumers were divided into different groups with respect to size and season. The measure of the competition was then answered quantitatively with two indexes (Pianka & Laubmeier). The results support the conclusion that small charr (<30 cm) was exposed of remarkably tough competition from whitefish regarding the older period. This derives from the fact that these two species show a very similar diet including Opossum shrimp (Mysis relicta) and Monoporeia affinis. With increasing size charr turns to a more piscivore diet and begins to compete with burbot. The piscivorous charr consumes mostly smelt (Osmerus eperlanus) while burbot shows a more diverse behavior of its selection of fish species as a resource. The fact that these three species can coexist despite tough competition likely derives from the fact that Vätterns food web contains a lot of actors at the lower trophic levels. Bachelor Thesis Arctic charr Arctic Burbot Lota lota lota University of Skövde: Publications (DiVA) Arctic |
institution |
Open Polar |
collection |
University of Skövde: Publications (DiVA) |
op_collection_id |
ftskoevdehoeg |
language |
Swedish |
topic |
Ecology Ekologi |
spellingShingle |
Ecology Ekologi Norén, Oskar Konkurrensen mellan röding, sik och lake i Vättern : En djupdykning i tre konsumenters födopreferenser. Två tidsperioder: 1964-1978 samt 2006-2011 |
topic_facet |
Ecology Ekologi |
description |
Lake Vättern contains Swedens most valuable population of arctic charr (Salvelinus umbla). The stock of this Salmonidae fish showed a negative trend for several decades but has now turned to a more positive one. Too minimize the risk of a new backlash it is important to obtain knowledge about the arctic charr and its interaction with other species. The purpose of this paper is to investigate the interspecific competition between arctic charr and two other valuable species i.e. whitefish (Coregonus maraena) and burbot (Lota lota). Data of stomach contents from two periods (1964-1978 & 2006-2011) were analyzed. The consumers were divided into different groups with respect to size and season. The measure of the competition was then answered quantitatively with two indexes (Pianka & Laubmeier). The results support the conclusion that small charr (<30 cm) was exposed of remarkably tough competition from whitefish regarding the older period. This derives from the fact that these two species show a very similar diet including Opossum shrimp (Mysis relicta) and Monoporeia affinis. With increasing size charr turns to a more piscivore diet and begins to compete with burbot. The piscivorous charr consumes mostly smelt (Osmerus eperlanus) while burbot shows a more diverse behavior of its selection of fish species as a resource. The fact that these three species can coexist despite tough competition likely derives from the fact that Vätterns food web contains a lot of actors at the lower trophic levels. |
format |
Bachelor Thesis |
author |
Norén, Oskar |
author_facet |
Norén, Oskar |
author_sort |
Norén, Oskar |
title |
Konkurrensen mellan röding, sik och lake i Vättern : En djupdykning i tre konsumenters födopreferenser. Två tidsperioder: 1964-1978 samt 2006-2011 |
title_short |
Konkurrensen mellan röding, sik och lake i Vättern : En djupdykning i tre konsumenters födopreferenser. Två tidsperioder: 1964-1978 samt 2006-2011 |
title_full |
Konkurrensen mellan röding, sik och lake i Vättern : En djupdykning i tre konsumenters födopreferenser. Två tidsperioder: 1964-1978 samt 2006-2011 |
title_fullStr |
Konkurrensen mellan röding, sik och lake i Vättern : En djupdykning i tre konsumenters födopreferenser. Två tidsperioder: 1964-1978 samt 2006-2011 |
title_full_unstemmed |
Konkurrensen mellan röding, sik och lake i Vättern : En djupdykning i tre konsumenters födopreferenser. Två tidsperioder: 1964-1978 samt 2006-2011 |
title_sort |
konkurrensen mellan röding, sik och lake i vättern : en djupdykning i tre konsumenters födopreferenser. två tidsperioder: 1964-1978 samt 2006-2011 |
publisher |
Högskolan i Skövde, Institutionen för biovetenskap |
publishDate |
2020 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-18066 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic charr Arctic Burbot Lota lota lota |
genre_facet |
Arctic charr Arctic Burbot Lota lota lota |
op_relation |
http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-18066 |
op_rights |
info:eu-repo/semantics/openAccess |
_version_ |
1766303931361656832 |