Author: Matthew Richard CampbellPublisher:
ISBN:
Category : Cutthroat trout
Languages : en
Pages : 168
Book Description
Hybridization and Introgression in a Managed, Native Yellowstone Cutthroat Oncorhynchus Clarki Bouvieri Population, Henrys Lake, Idaho
Author: Matthew Richard CampbellPublisher:
ISBN:
Category : Cutthroat trout
Languages : en
Pages : 168
Book Description
Hybridization and Introgression in a Managed, Native Population of Yellowstone Cutthroat Trout: Genetic Detection and Management Implications
Author: Matthew R. CampbellPublisher:
ISBN:
Category : Cutthroat trout
Languages : en
Pages : 12
Book Description
Since the mid-1920s, the Idaho Department of Fish and Game has cultured Yellowstone cutthroat trout Oncorhynchus clarki bouvieri at Henrys Lake to offset declines in natural production and for use in stocking programs throughout Idaho. Since the mid-1970s, they have also produced F1 hybrids: female Yellowstone cutthroat trout * male rainbow trout O. mykiss. The ability of fishery managers, when selecting broodstock, to visually distinguish returning cutthroat trout from F1 hybrids is, therefore, crucial to avoid accidental introduction of rainbow trout genes into the hatchery-supplemented cutthroat trout population. To evaluate this ability, fish identified by staff as putative cutthroat trout or hybrids (an array of phenotypic characters are used), were sampled during two spawning seasons. Phenotypically identified fish were genetically tested using species-specific restriction fragment length polymorphisms (RFLPs) of nuclear and mitochondrial DNA gene loci and diagnostic allozyme loci. Current levels of rainbow trout introgression in the cutthroat trout population at Henrys Lake were also investigated by analyzing samples collected from the lake and several of its tributaries. Results indicated that staff's phenotypic identifications were highly accurate in distinguishing cutthroat trout from F1 hybrids when selecting broodstock (no F1 hybrids were detected among 80 samples identified as pure). However, backcrosses of F1 hybrids were identified in random collections of adults from the lake as well as fry from Henrys Lake tributaries, indicating introgression. Present levels of rainbow trout introgression are most likely the product of past rainbow trout introductions and limited, intermittent spawning of hatchery-produced F1 hybrids with wild Yellowstone cutthroat, rather than the accidental crossing of F1 hybrids with cutthroat trout at the hatchery. Current levels of introgression are inadvertently maintained by (1) the inability of managers to phenotypically identify and exclude as broodstock individuals with low levels of rainbow trout introgression and (2) the limited, intermittent reproductive success of straying, hatchery-produced F1 hybrids.--Abstract.
Master's Theses Directories
Author: Publisher:
ISBN:
Category : Dissertations, Academic
Languages : en
Pages : 396
Book Description
"Education, arts and social sciences, natural and technical sciences in the United States and Canada".
Bring Back the Lahontan Cutthroat
Author: Status and Management of Interior Stocks of Cutthroat Trout
Author: Robert E. GresswellPublisher:
ISBN:
Category : Cutthroat trout
Languages : en
Pages : 162
Book Description
Geologic Field-trip Guide to the Volcanic and Hydrothermal Landscape of the Yellowstone Plateau
Author: Lisa A. MorganPublisher: Government Printing Office
ISBN: 9781411342040
Category : Calderas
Languages : en
Pages : 116
Book Description
Conservation Assessment for Inland Cutthroat Trout
Author: Donald A. DuffPublisher: DIANE Publishing
ISBN: 0788145673
Category :
Languages : en
Pages : 199
Book Description
This document focuses on the current status, distribution and range for five subspecies of cutthroat trout Oncorhynchus clarki, which are found largely on national forest system lands and ecosystems in the Rocky Mountain and Intermountain West within the U.S. from the Canadian to the Mexican border. The 5 subspecies -- Westslope, Yellowstone, Bonneville, Rio Grande, and Colorado River cutthroat trout -- are designated either species of special concern or sensitive. These subspecies are presently restricted to a fragment of their former range. Includes assessment methods, and origins and taxonomic theory. Illustrated.
Sport Fish Restoration
Author: United States. Bureau of Sport Fisheries and WildlifePublisher:
ISBN:
Category : Fish-culture
Languages : en
Pages : 32
Book Description
Fisheries and Wildlife Research
Author: U.S. Fish and Wildlife ServicePublisher:
ISBN:
Category : Fisheries
Languages : en
Pages : 180
Book Description
Report on activities in the Divisions of Cooperative Research, Cultural Methods Research, Population Ecology Research, and Population Regulation Research.
Fluctuations in Age Composition and Growth Rate of Cutthroat Trout in Yellowstone Lake
Author: Ross V. BulkleyPublisher:
ISBN:
Category : Cutthroat trout
Languages : en
Pages : 40
Book Description
Age composition, growth rate, and year-class strength of Yellowstone Lake cutthroat trout from collections made in 1948 and from 1950 to 1959 are analyzed to relate total catch changes in age composition and growth rate. An increase in growth rate of fish fully recruited to the fishery and a decrease in percentages of fish belonging to age groups VI and VII are attributed to an increase in fishing pressure. Mean age of the catch varied with year-length of the catch has remained high, suggesting that production is more efficient now than in past years. Maximum equilibrium yield may be near. If the catch continues to increase at the present rate, it may become excessive within the next few years.