I assessed the relationship between growth of fish in situ, food consumption, prey type and fish community descriptors in 12 perch (Perca flavescens) populations exhibiting a 1.8 to 10-fold range in growth rates. / Perch growth rates consistently decreased as fish numerical density increased (r$ sp2$ = 0.60) and increased as feeding levels increased (r$ sp2$ = 0.30). I found no significant relationship between the quantity of food consumed by perch and fish numerical density. Prey quality explained from 50 to 95% of the observed variability in growth but was related to fish numerical density in only one of the 3 perch age classes studied. / I conclude that non-exploitative interactions (operating through increased activity costs) is a more viable explanation for the among-population variability in fish growth rates than is exploitative competition (yielding decreases in the total quantities of food consumed and/or prey quality).
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.75957 |
| Date | January 1988 |
| Creators | Boisclair, Daniel |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Department of Biology.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 000925743, proquestno: AAINL52456, Theses scanned by UMI/ProQuest. |
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