The effect of sedimentation on the natural recruitment of brown trout (Salmo trutta), in small Danish streams

John Conallin

Studenteropgave: Semesterprojekt

Abstrakt

Deposition rates of fine sediment into egg baskets situated in simulated Salmo trutta redds were measured during the winter of 2002-2003. The survival of Salmo trutta alevins were recorded to assess if sedimentation was having a detrimental effect on natural recruitment levels within the stream River Langvad. River Ledreborg an almost pristine stretch of stream was used as the control. Both streams are situated in the County of Roskilde, Denmark and are representative of many of the small streams situated in western Denmark. Sedimentation was found to be having an effect on the natural recruitment levels in River Langvad as no survival of alevins was recorded. A combination of factors was more than likely to have led to such a result. More surprisingly was the finding of high sedimentation in the River Ledreborg and as a result of this sedimentation, low natural recruitment levels were recorded. Management issues and recommendations on the appropriate measures that need to be taken into account to rehabilitate these two streams are also discussed.

UddannelserTekSam - miljøplanlægning, (Bachelor/kandidatuddannelse) Kandidat
SprogEngelsk
Udgivelsesdato1 jun. 2003

Emneord

  • Salmo trutta
  • Natural recruitment
  • Anthropogenic sources
  • Danish streams
  • Fish habitat
  • Sedimentation
  • Nationalpark Skjoldungernes Land