3 edition of Examination of the ecology of the cisco (Coregonus artedii) in Ontario lakes found in the catalog.
Source: Dissertation Abstracts International, Volume: 67-07, Section: B, page: 3559.Thesis (Ph.D.)--University of Toronto, 2006.Includes bibliographic references.Electronic version licensed for access by U. of T. users.
|The Physical Object|
|Pagination||xvi, 66 p. :|
|Number of Pages||88|
This research explores two aspects of cisco ecology: life history variation and behavioral variation. The life history investigation encompasses a spatial comparison of the life histories exhibited by populations from across Ontario; an assessment of changes made in life history exhibited by several populations over several decades; and an examination of the association between variation in life history and variation in the character of the higher trophic levels that are supported by cisco. Results indicate that there is a broad range in maximum attainable size, growth, condition and size at maturity, and these characteristics show strong positive correlations with one another. These traits had weak relationships with environmental measures of primary productivity (total dissolved solids), however the structure of the predator community (specifically the presence of walleye) was linked with larger body sizes and associated traits. Results from a detailed examination of the establishment of 3 new, independent and self-sustaining populations from the introduction of a single stock into three separate water-bodies in 1948, suggest that the life history strategy of a population of cisco can shift over short time scales (25 years or less). These life history shifts appear to be the result of plastic changes in phenotype, and are precipitated by significant changes in the predator community. Shifts in life history strategies can actually prevent the predator population from regaining the position once held in the community. The impact of predation on cisco behaviour was also examined. Results suggest that the presence of a visual predator increases the size of schools that cisco form during the day and forces those schools deeper into the water column, into less favorable environments. However, the presence of a visual predator does not impact the timing of school dissociation at the end of the day or the nighttime behavior itself. These findings are put into a larger context that emphasizes the importance of environmental characteristics and community characteristics in shaping the observed life history and behaviour of cisco populations. File Size: 6MB.
Additional support has come from the Marisla Foundation, UM College of Literature, Science, and the Arts, Museum of Zoology, and Information and Technology Services.
During summer warming, the adults migrate to the hypolimnion, which ranges from 2. Aquatic Research and Monitoring Section, Ontario Ministry of Natural Resources and Forestry, Peterborough, ON, Canada Scott M.
Cisco larvae are caught in the highest densities at the surface, regardless of water depth Pritchard, ; Faber, ; Clady. US Bur Fish Bull 43:297—643• in Canada, overseen and edited by Robert Campbell, Claude Renaud, and Eric Taylor, Co-chairs, COSEWIC Freshwater Fishes Specialist Subcommittee.
1991; Aku and Tonn 1997. Revised Edition Smith, GR University of Michigan Press, Ann Arbor• Lake Superior is the only lake where ciscoes are abundant; low populations are characteristic of lakes Erie, Michigan, Ontario, and Huron. artedi, stating that more detailed scientific studies are required before any conclusions linking the other species with C.
— Sport Fish Contaminants Modelling• Clarke RM 1973 The systematics of ciscoes Coregonidae in central Canada. Differentiation in Coregonus zenithicus in Lake Superior.
Typical lifespan Status: wild 6 to 10 years Behavior Ciscoes move constantly.
They also would like to thank Claude Renaud, Daniel Banville, James D.
Coregonid fishes of the Great Lakes.
, ; Reed et al.
The two species are challenging to distinguish at the larval stage before the Lake Whitefish mouth has differentiated and become subterminal Fudge et al.
Papers of the Michigan Academy of Sciences 43: 107-118.