Ecology and performance of stocked brook trout (Salvelinus fontinalis) in two Maine ponds

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منو

" Ecology and performance of stocked brook trout (Salvelinus fontinalis) in two Maine ponds "
C. F. Hartleb J. R. Moring

Document Type	:	Latin Dissertation
Language of Document	:	English
Record Number	:	1113081
Doc. No	:	TLpq304245996
Main Entry	:	C. F. Hartleb
	:	J. R. Moring
Title & Author	:	Ecology and performance of stocked brook trout (Salvelinus fontinalis) in two Maine ponds\ C. F. HartlebJ. R. Moring
College	:	The University of Maine
Date	:	1996
student score	:	1996
Degree	:	Ph.D.
Page No	:	210
Abstract	:	Performance by stocked brook trout (Salvelinus fontinalis) differs with respect to the native species present in the community into which the trout are placed. Understanding the dietary and habitat requirements of the native species, and how the brook trout alter the ecosystem, can lead to better trout management. I investigated diet composition and prey abundance and location in order to determine the foraging habitat and dietary overlap of non-salmonid species in two Maine ponds that received hatchery-reared brook trout. Golden shiners (Notemigonus crysoleucus) and chain pickerel (Esox niger) had specialized diets, feeding on plants/algae and other fish, respectively. Yellow perch (Perca flavescens) and pumpkinseeds (Lepomis gibbosus) had broad diets, but coexisted because of abundant prey and habitat partitioning. Stocked brook trout growth and survival were poor in one pond because of unsuitable temperature and oxygen conditions. Brook trout were restricted to foraging in epipelagic water, which altered the foraging patterns of yellow perch. The diet of brook trout stocked in the other pond did not overlap with any other species and brook trout occupied foraging habitat that was underutilized by the fish community. Introduced brook trout did not seem to affect the interactions of the native species, and the brook trout appeared to fill a niche where suitable temperature, oxygen and prey allowed continued survival. In the final section of this study, I developed a bioenergetics model based on a synthesis of studies on the energetics of brook trout and other salmonids. Temperatures that exceeded optimal conditions for brook trout decreased growth and survival. Lowest maintenance rations were required by brook trout at 13C and by smaller-sized trout. Food limitations and interspecific competition affected larger brook trout less than smaller-sized fry. No differences were observed in the survival and growth of fall-fingerling and spring-yearling brook trout and either size could be stocked when conditions are sub-optimal.
Subject	:	Aquaculture
	:	Biological sciences
	:	Ecology
	:	Fish production
	:	Freshwater ecology
	:	Zoology