RNA/DNA ratio and total length of yellow perch (Perca flavescens) in managed and natural wetlands of a large fluvial lake

$50.00 plus tax (Refund Policy)

Buy Article:

Abstract:

RNA/DNA ratios and total lengths were compared to determine growth patterns of age-0 yellow perch (Perca flavescens) in managed and natural habitats of a large fluvial lake (Lake Saint-Pierre, St. Lawrence River, Quebec, Canada) over seasonal and yearly temporal scales. In 2002, the RNA/DNA ratio responded to degree-days accumulated over periods of 7–8 days before sampling, while in 2003, no relationship with temperature was established. The growth patterns obtained each year probably reflect indices responding to different limiting variables. In 2002, temperature would have been limiting, whereas in 2003, other factors such as prey availability, food quality, and competition may have influenced growth. In addition, the discrepancy between total length and RNA/DNA ratio observed in 2003 may reflect a differential time of response to limiting variables. These results together show that the two indices reflect growth at different time scales and suggest that their combination can help identify shifts between limiting environmental variables. Also, growth in managed wetlands during springtime was systematically superior to that in the natural environment, supporting the contention that managed wetlands are highly productive habitats. In natural habitats, growth rates were higher on the south shore by summer, which is consistent with the established north-south productivity gradient in Lake Saint-Pierre.

La comparaison des rapports ARN/ADN et des longueurs totales chez des perchaudes (Perca flavescens) d’âge 0 nous a servi à déterminer les patrons de croissance dans des habitats aménagés et naturels d’un grand lac fluvial sur des échelles temporelles saisonnières et annuelles. Le rapport ARN/ADN en 2002 réagit aux degrés-jours accumulés sur des périodes de 7–8 jours avant l’échantillonnage, alors qu’en 2003 il n’y a pas de relation avec la température. Les patrons de croissance obtenus chaque année reflètent probablement des indices qui réagissent à différentes variables limitantes. En 2002, la température aurait été le facteur limitant, alors qu’en 2003 d’autres facteurs, tels que la disponibilité des proies, la qualité de la nourriture et la compétition auraient pu influencer la croissance. De plus, le désaccord entre les longueurs totales et les rapports ARN/ADN observé en 2003 peut peut-être s’expliquer par des temps différents de réaction aux variables limitantes. Dans leur ensemble, ces résultats montrent que les deux indices illustrent la croissance à deux échelles temporelles différentes; leur combinaison peut vraisemblablement aider à identifier les changements de variables environnementales limitantes. De plus, la croissance dans les terres humides aménagées au printemps est systématiquement plus forte que dans les milieux naturels, ce qui appuie l’idée que les terres humides aménagées sont des habitats de très grande productivité. Dans les habitats naturels, la croissance est plus forte en été sur la rive sud, ce qui est compatible avec le gradient nord-sud de productivité établi au lac Saint-Pierre.

Document Type: Research Article

Publication date: October 1, 2005

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