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Updated: Aug 9, 2026
12:24
Laboratory Estimation of Net Trophic Transfer Efficiencies of PCB Congeners to Lake Trout (Salvelinus namaycush) from Its Prey
Published on: August 29, 2014
Common and rare trout parasites in a small landscape system
1Zoological Museum, University of Oslo, Norway.
Parasitology
|January 1, 1993
Summary
Brown trout host nine helminth species, with core species like Crepidostomum metoecus showing superior colonization. This supports the
Area of Science:
- Ecology
- Parasitology
- Ichthyology
Background:
- Brown trout (Salmo trutta) populations in close proximity can exhibit distinct parasite communities.
- Understanding helminth species distribution is crucial for assessing host-parasite dynamics and ecosystem health.
Purpose of the Study:
- To investigate the helminth species composition in brown trout from four lakes within a 40 km2 area.
- To classify helminth species based on their occurrence and distribution patterns (core, intermediate, satellite).
- To evaluate the colonization ability of different helminth species using salmon (Salmo salar) fingerlings and test ecological hypotheses.
Main Methods:
- Sampling of brown trout from four geographically proximate lakes.
- Identification and quantification of helminth species harbored by the trout.
- Experimental infection of salmon fingerlings with helminth species to assess colonization.
- Analysis of species distribution patterns to classify them as core, intermediate, or satellite.
Main Results:
- Nine helminth species were identified in the brown trout.
- Crepidostomum metoecus was classified as a core species, and Crepidostomum farionis as intermediate.
- Other helminth species were classified as satellite species.
- Salmon fingerlings experimentally infected with helminths suggested superior colonization by core species (Crepidostomum spp.).
Conclusions:
- The study identified a diverse helminth fauna in brown trout, with distinct community structures.
- Core helminth species demonstrated a higher colonization ability, as evidenced by their presence and experimental infection success.
- Findings support the 'rescue effect hypothesis' over the 'carrying capacity hypothesis' in explaining parasite distribution patterns.
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