Temporal and spatial variation in the energy intake of a brook trout (Salvelinus fontinalis) population in an Appalachian watershed

$50.00 plus tax (Refund Policy)

Buy Article:

Abstract:

Stream-dwelling salmonids in eastern North America are often restricted to headwater watersheds, where productivity is low and thus feeding conditions are poor. We sought to quantify how energy intake varies with spatial and temporal variation by monitoring feeding rates in multiple sites over the course of two years. Daily rations were calculated for 939 fish by examining stomach contents. Maintenance rations were compared with daily rations using a bioenergetics model. Consumption peaked in spring, dropped substantially in summer, and remained low until the following spring. A minority of fish fed at very high levels during all seasons, elevating the mean consumption of the population. Fish occupying large sites with low trout densities consistently consumed more energy than fish in smaller streams with high trout densities. A direct relationship between trout density and mean consumption was observed during summer, when feeding conditions were poorest. Our findings suggest that within a headwater watershed, larger reaches of streams where fewer trout are found act as important feeding areas and thus may be important habitat for brook trout (Salvelinus fontinalis).

Les salmonidés des cours d'eau dans l'est de l'Amérique du nord sont souvent confinés aux bassins versants d'amont où la productivité est faible et conséquemment les conditions alimentaires médiocres. Nous avons cherché à mesurer les variations spatiales et temporelles de l'ingestion d'énergie en suivant les taux d'alimentation à plusieurs sites durant deux années. L'analyse des contenus stomacaux de 939 poissons a permis de calculer les rations journalières. Un modèle bioénergétique a comparé les rations journalières aux rations de maintien. La consommation atteint un maximum au printemps, diminue considérablement en été et reste faible jusqu'au printemps suivant. Un minorité de poissons se nourrit à un taux élevé en toutes saisons, ce qui augmente la consommation moyenne de la population. Les poissons habitant de grands sites à faibles densités d'ombles consomment toujours plus d'énergie que les poissons dans les petits cours d'eau à forte densité d'ombles. On observe une relation directe entre la densité des ombles et la consommation moyenne en été, quand les conditions d'alimentation sont les moins bonnes. Nos observations indiquent que, dans un bassin versant d'amont, les grandes sections habitées par un nombre réduit d'ombles sont des lieux importants d'alimentation et peuvent donc être un habitat vital pour l'omble de fontaine (Salvelinus fontinalis).[Traduit par la Rédaction]

Document Type: Research Article

Publication date: December 1, 2006

More about this publication?
  • Published continuously since 1901 (under various titles), this monthly journal is the primary publishing vehicle for the multidisciplinary field of aquatic sciences. It publishes perspectives (syntheses, critiques, and re-evaluations), discussions (comments and replies), articles, and rapid communications, relating to current research on cells, organisms, populations, ecosystems, or processes that affect aquatic systems. The journal seeks to amplify, modify, question, or redirect accumulated knowledge in the field of fisheries and aquatic science. Occasional supplements are dedicated to single topics or to proceedings of international symposia.
  • Information for Authors
  • Submit a Paper
  • Subscribe to this Title
  • Terms & Conditions
  • Sample Issue
  • Reprints & Permissions
  • ingentaconnect is not responsible for the content or availability of external websites
Related content

Tools

Favourites

Share Content

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
X
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more