Identification by scales of hatchery and wild chinook salmon (Oncorhynchus tshawytscha) in the Credit River, Ontario.
Published: 2004
Language: eng
Number of pages: 93
Description: Lake Ontario contains both hatchery- and wild-origin chinook salmon (Oncorhynchus tshawytscha), however, researchers do not know the relative proportions and do not have a technique to identify origin. This thesis provides an origin-determination technique based on scale analysis and identifies proportions of hatchery and wild adult chinook in the Credit River. Analysis revealed that the 3-axes method provided a discriminant function with the highest classification level (85.7% with a jackknife cross-validation of 81%). The discriminant function was developed based solely on differences of scale characteristics between hatchery and wild fish. Specifically, the characteristics that were utilized were: focus, STD 3--6, circuli 1, circuli 5, and circuli 2--4. Using this discriminant function, 58%--74% of spawning adults in the Credit River were determined to be of wild origin. Thus, we now have an assessment technique and first scientific calculation of the proportion of wild chinook salmon.
Notes: Adviser:  Mart Gross.

Thesis (M.Sc.)--University of Toronto, 2004.

Electronic version licensed for access by U. of T. users.

Source: Masters Abstracts International, Volume: 42-06, page: 2126.

MICR copy on microfiche (2 microfiches).