Diel feeding rhythms and daily food consumption of juvenile Atlantic salmon in the River Alta, northern Norway

Atlantic salmon fry (0+) sampled from the River Alta exhibited only minor differences in stomach content weights and feeding rates throughout diel periods, but feeding rates were generally lowest at night. In contrast, salmon parr (1+ to 3+) had large diel fluctuations in stomach content weight, wit...

Full description

Bibliographic Details
Published in:Journal of Fish Biology
Main Authors: Amundsen, P.‐A., Bergersen, R., Huru, H., Heggberget, T. G.
Format: Article in Journal/Newspaper
Language:English
Published: Wiley 1999
Subjects:
Online Access:http://dx.doi.org/10.1111/j.1095-8649.1999.tb00612.x
https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1095-8649.1999.tb00612.x
https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1095-8649.1999.tb00612.x
Description
Summary:Atlantic salmon fry (0+) sampled from the River Alta exhibited only minor differences in stomach content weights and feeding rates throughout diel periods, but feeding rates were generally lowest at night. In contrast, salmon parr (1+ to 3+) had large diel fluctuations in stomach content weight, with the largest weights usually being recorded during the night and early morning. Accordingly, their feeding rates were highest at night. This nocturnal feeding pattern was consistent throughout all sampling occasions, and appeared to reflect a persistent feeding periodicity in the salmon parr. The daily food consumption rates of both fry and parr were highest during midsummer and decreased towards autumn.