@article{PAR00009451,
  title = {{E}xperimental study of the influence of photoperiod and temperature on the swimming behaviour of hatchery-reared {A}tlantic salmon ({S}almo salar {L}.) smolts},
  author = {{M}artin, {P}. and {R}ancon, {J}. and {S}egura, {G}. and {L}affont, {J}. and {B}oeuf, {G}. and {D}ufour, {S}ylvie},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he impacts of photoperiod and temperature on the swimming behaviour of hatchery-reared {A}tlantic salmon smolts were investigated, with a view to optimising salmon restoration strategies in the {L}oire-{A}llier basin. {A} novel experimental design was developed to study individual tagged fish in 9 m diameter hatchery tanks. {M}ovements and swimming speeds were recorded over a period of eight months ({J}anuary to {A}ugust), repeated over four consecutive years (2005-2008). {F}ish switched from positive rheotactic behavior in {J}anuary-{F}ebruary, to negative rheotactic behaviour at mid-{M}arch or {A}pril depending on the year, a period corresponding to the start of the downstream migration of wild smolts from the upper river spawning areas. {D}aily variation in movement and swimming speed occurred with high swimming speeds with the flow during the day and much lower speeds during the night. {S}wimming speeds could exceed water current velocity, showing hatchery-reared salmon can actively swim with the flow during the day. {E}xperimental changes of photoperiod (constant light or constant darkness) allowed confirmation of the role of photoperiod in the daily variation of swimming activity. {A}nalysis of the relationship between water temperature and swimming speeds over the four year experiments suggested a major role for water temperature in the modulation of swimming activity. {M}aximal swimming speed was recorded at 10.5 degrees {C} and swimming speed was reduced by 80% for temperatures under 4 or above 17 degrees {C}. {F}ish stopped moving above 20 degrees {C}. {T}he data highlight the importance of temperature for the modulation of downstream movement, as well as the potential deleterious impact of the anthropogenic increase in river temperature below the spawning and juvenile habitat in the {A}llier tributary on the success of downstream migration. {B}etter understanding of temperature effects on actual population-specific in-river migration patterns is required to allow managers to identify mitigation measures needed to improve migration success.},
  keywords = {{L}oire-{A}llier {R}iver ; {D}ownstream migration ; {S}wimming speed ; {A}ctive-passive ; movement ; {P}it tag},
  booktitle = {},
  journal = {{A}quaculture},
  volume = {362},
  numero = {},
  pages = {200--208},
  ISSN = {0044-8486},
  year = {2012},
  DOI = {10.1016/j.aquaculture.2011.11.047},
  URL = {https://www.documentation.ird.fr/hor/{PAR}00009451},
}