Pre-spawning habitat selection of subarctic brown trout (Salmo trutta L.) in the river Vindelälven, Sweden
Habitat selection of migratory brown trout at the upper reaches of River Vindelälven, was studied in September during the pre-spawning period. The fish migrate from down- or upriver lakes for spawning in the river and data was collected by habitat mapping and radio-telemetry. Habitat selection of fi...
| Autor principal: | |
|---|---|
| Formato: | Second cycle, A1E |
| Lenguaje: | sueco Inglés |
| Publicado: |
2011
|
| Materias: | |
| Acceso en línea: | https://stud.epsilon.slu.se/2423/ |
| _version_ | 1855570430917607424 |
|---|---|
| author | Spade, Erik |
| author_browse | Spade, Erik |
| author_facet | Spade, Erik |
| author_sort | Spade, Erik |
| collection | Epsilon Archive for Student Projects |
| description | Habitat selection of migratory brown trout at the upper reaches of River Vindelälven, was
studied in September during the pre-spawning period. The fish migrate from down- or
upriver lakes for spawning in the river and data was collected by habitat mapping and
radio-telemetry. Habitat selection of fish was analysed with preference curves and
statistical modelling, using the physical variables; depth, stream velocity and streambed
substrate. Preference curves were derived by comparing fish habitat use with their nearby
available environment while the statistical modelling aimed to answer three main questions.
1) Do the trout have a specific preference of depth, water velocity and streambed substrate?
2) Is there any difference in habitat selection between sexes? 3) Is there a shift in habitat
selection over time? The preference curves indicated that trout favored water depths of 1-2
m, velocity compositions characterized as glides (c. 0.2-0.4 m s-1), both fine (0.02-2 mm)
and large (>200 mm) substrate compositions. The overall habitat selection of fish was
significantly influenced by all three investigated physical variables. Stream velocity was the
only factor statistically segregating females and males in habitat selection, where males
used higher velocity areas. No shifts in habitat selection over the one month study period
were found. The complexity of streams and correlations between variables often results in
difficulties to evaluate fish habitat preferences and consequently future challenges lies in
the development of models accounting for a wider range of abiotic and biotic factors.
|
| format | Second cycle, A1E |
| id | RepoSLU2423 |
| institution | Swedish University of Agricultural Sciences |
| language | swe Inglés |
| publishDate | 2011 |
| publishDateSort | 2011 |
| record_format | eprints |
| spelling | RepoSLU24232012-04-20T14:18:35Z https://stud.epsilon.slu.se/2423/ Pre-spawning habitat selection of subarctic brown trout (Salmo trutta L.) in the river Vindelälven, Sweden Spade, Erik Aquatic ecology Habitat selection of migratory brown trout at the upper reaches of River Vindelälven, was studied in September during the pre-spawning period. The fish migrate from down- or upriver lakes for spawning in the river and data was collected by habitat mapping and radio-telemetry. Habitat selection of fish was analysed with preference curves and statistical modelling, using the physical variables; depth, stream velocity and streambed substrate. Preference curves were derived by comparing fish habitat use with their nearby available environment while the statistical modelling aimed to answer three main questions. 1) Do the trout have a specific preference of depth, water velocity and streambed substrate? 2) Is there any difference in habitat selection between sexes? 3) Is there a shift in habitat selection over time? The preference curves indicated that trout favored water depths of 1-2 m, velocity compositions characterized as glides (c. 0.2-0.4 m s-1), both fine (0.02-2 mm) and large (>200 mm) substrate compositions. The overall habitat selection of fish was significantly influenced by all three investigated physical variables. Stream velocity was the only factor statistically segregating females and males in habitat selection, where males used higher velocity areas. No shifts in habitat selection over the one month study period were found. The complexity of streams and correlations between variables often results in difficulties to evaluate fish habitat preferences and consequently future challenges lies in the development of models accounting for a wider range of abiotic and biotic factors. Habitatval hos vandrande öring, med sitt huvudsakliga utbredningsområde i övre delarna av Vindelälven, studerades under september en månad innan lek. Data på djup, vattenhastighet och bottensubstrat samlades in genom biotopkartering, och telemetristudier visade fiskens ståndplatsval. Öringarnas habitatval analyserades med preferenskurvor, baserade på data av utnyttjande och tillgång av olika habitat, samt statistisk modellering baserat på tre frågor. 1) Har öring en specifik preferens för djup, vattenhastighet och bottensubstrat? 2) Finns det någon skillnad i habitatval mellan könen? 3) Finns det skillnader i val av habitat över tid? Preferenskurvorna indikerade att öringen föredrog djup av 1-2 m, områden med ett dominerande inslag av svagt strömmande vatten (c. 0.2-0.4 m s-1), samt bottnar med både fina (0.02-2 mm) och grova (>200 mm) sammansättningar av substrat. Alla tre variabler inverkade signifikant på fiskens habitatval. Vattenhastighet var den enda faktorn som statistiskt skilde könens val av habitat, då hanar föredrog en högre hastighet än honor. Inga skiften i habitatval i relation till tid, över den månad som studien pågick, var möjliga att urskilja. Komplexiteten i strömmande vatten och en korrelation mellan olika variabler resulterar ofta i svårigheter i att skatta fiskens habitatpreferens, där framtida utmaningar ligger i att utveckla modeller som kan analysera en större mängd abiotiska samt biotiska data. 2011-04-05 Second cycle, A1E NonPeerReviewed application/pdf swe https://stud.epsilon.slu.se/2423/1/Spade_E_110405.pdf Spade, Erik, 2011. Pre-spawning habitat selection of subarctic brown trout (Salmo trutta L.) in the river Vindelälven, Sweden. Second cycle, A1E. Umeå: (S) > Dept. of Wildlife, Fish and Environmental Studies <https://stud.epsilon.slu.se/view/divisions/OID-251.html> urn:nbn:se:slu:epsilon-s-14 eng |
| spellingShingle | Aquatic ecology Spade, Erik Pre-spawning habitat selection of subarctic brown trout (Salmo trutta L.) in the river Vindelälven, Sweden |
| title | Pre-spawning habitat selection of subarctic brown trout (Salmo trutta L.) in the river Vindelälven, Sweden |
| title_full | Pre-spawning habitat selection of subarctic brown trout (Salmo trutta L.) in the river Vindelälven, Sweden |
| title_fullStr | Pre-spawning habitat selection of subarctic brown trout (Salmo trutta L.) in the river Vindelälven, Sweden |
| title_full_unstemmed | Pre-spawning habitat selection of subarctic brown trout (Salmo trutta L.) in the river Vindelälven, Sweden |
| title_short | Pre-spawning habitat selection of subarctic brown trout (Salmo trutta L.) in the river Vindelälven, Sweden |
| title_sort | pre-spawning habitat selection of subarctic brown trout (salmo trutta l.) in the river vindelälven, sweden |
| topic | Aquatic ecology |
| url | https://stud.epsilon.slu.se/2423/ https://stud.epsilon.slu.se/2423/ |