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H. L. Kincaid

Publications and source records attributed to H. L. Kincaid.

At least 19 recordsLinked to original sources
USGS2003

Genetic comparison of lake sturgeon populations: Differentiation based on allelic frequencies at seven microsatellite loci

The lake sturgeon (Acipenser fulvescens) has recently become a high priority for restoration management because of the near extinction of the species from many areas of North America. The identification of the level of population differentiation that naturally exists among lake sturgeon populations will be useful in the development of management plans to conserve and restore diversity, and in the choice of donor populations to use for re-introduction. Genetic variation among and within 210 lake sturgeon collected from seven locations (St. Lawrence River, Des Prairies River (tributary to the St. Lawrence River), Mattagami River (Hudson Bay drainage), Menominee River (Lake Michigan drainage), Wolf River (Lake Michigan drainage), Niagara River, and Lake Erie) was examined based on allelic variation at seven microsatellite loci (four disomic and three putative tetrasomic). High levels of variability were detected at these loci. Analyses revealed an average of 8.6 alleles per locus (range 5 to 12 alleles per locus) and heterozygosity values at the four disomic loci ranging from 0.46 to 0.66. Multivariate factor analysis of Nei's genetic distance values produced three distinct population groups that were organized by geography: 1) Mattagami (northern Quebec), 2) Menominee/ Wolf (Lake Michigan - Wisconsin), and 3) St. Lawrence/ Des Prairies/ Niagara/ Erie (lower Great Lakes). Differences based on G-tests summed over all loci occurred between all possible paired comparisons of the collections (P < 0.01). These analyses indicated that lake sturgeon populations are differentiated within the Great Lakes basin. Managers of this species will need to identify individual populations in their jurisdictions and provide separate consideration for their conservation and rehabilitation.

Journal of Great Lakes Research↗
USGS1994

Hatchery performance of six Atlantic salmon stocks from fry to smolt

Atlantic salmon ( Salmo salar ) from four Penobscot River, Maine, brood stocks (two wild and two captive) and two landlocked brood stocks (Grand Lake, Maine, and Lake George, New York) were evaluated in hatchery tests to measure differential performance characteristics. Each stock was received as eyed eggs and cultured under standardized rearing conditions through 16 months. Penobscot stocks did not differ in growth rate or time of smoltification but did differ in frequency of six of seven body abnormality traits. Domestication effects on postyearling weights and smolt ATPase levels were detected in Penobscot stocks. The Grand Lake landlocked stock had a higher growth rate after 245 d and was heavier than Penobscot stocks after 280 d (36%) and 480 d (58%). Although differences among the Penobscot stocks were small and generally nonsignificant, the presence of domestication effects on 17‐month weight and Na + K + ‐ATPase indicates that progeny from fish held in the hatchery for four generations exhibited different hatchery performance characteristics than progeny from sea‐run parents.

Progressive Fish-Culturist↗
USGS1993

Genetic comparison of naturally spawned and artificially propagated Lake Ontario lake trout fry: Evaluation of a stocking strategy for species rehabilitation

Two strategies have been used in the effort to restore lake trout Salvelinus namaycush to Lake Ontario. First, lake trout strains from multiple wild and hatchery sources have been stocked to maximize genetic variability in the lake, Second, a unique hatchery “strain” of fish to be stocked was created each year with gametes collected from adult, hatchery‐origin fish that had survived to maturity after being stocked into Lake Ontario. Several hatchery strains may be represented among the adults captured and used to propagate this unique strain, termed the “Ontario strain.” The “Ontario strain” may have a genetically based potential for enhanced survival over other strains stocked in Lake Ontario because it is composed of the progeny of fish that have survived from the yearling to the adult life stage, Unlike naturally spawned fish, however, the “Ontario strain” has been shielded from natural selection during the critical period of mortality from spawning through the first year of life, The purpose of this study was to determine whether the “Ontario strain” was genetically representative of the wild fry produced in the lake, We examined the strain composition of three year‐classes of wild‐caught fry and six year‐classes of the “Ontario strain” using allozyme data with mixed‐stock analysis. The hatchery and wild fry were genetically dissimilar. In addition, the composition of the “Ontario strain” changed from predominantly Seneca strain in 1983–1984 to predominantly Superior and Killala strains from 1983 to 1989. Mixed‐stock estimates indicated that in contrast to the hatchery‐reared fry, strain composition of wildcaught fry did not vary greatly from year to year. Progeny of Seneca × Seneca crosses were the predominant fry in the three year‐classes of wild fry. The genetic dissimilarity between the “Ontario strain” fry and wild‐caught fry could be caused by differential mortality among the wild fry between spawning and fry emergence or by differential vulnerability of strains to the gill‐net sampling used to capture adults for gamete collection. Based on these results, the development of a new hatchery brood stock from wild‐caught fry is recommended as an alternative to the collection and propagation of gametes from mature hatchery‐origin lake trout. In addition, the composition of the hatchery strains stocked should be altered to emphasize those strains that reproduce successfully. Both options should be considered in order to speed the rehabilitation process.

Lake Ontario↗
USGS1993

Preservation of genetic variation in the Green Lake strain lake trout derived from remnant domestic and feral populations

The Green Lake, Wisconsin, strain of lake trout Salvelinus namaycush was discontinued as a hatchery brood stock in 1976 after Lake Michigan was stocked with the 1975 year‐class. In 1982, a decision was made to restore the Green Lake strain as a production brood stock. Five groups were produced by spawning marked fish that were survivors from the 1976 stocking of southern Lake Michigan. A sixth group was produced from a remnant of the Green Lake brood stock held at the Genoa (Wisconsin) National Fish Hatchery. Hatchery accidents reduced both the number of groups and the effective population number of each group. We studied a procedure for reconstructing a composite Green Lake brood stock from individuals of these six groups. Genetic variability was evaluated by allozyme electrophoresis in five of these groups. Twelve of 18 loci were polymorphic. Allelic frequencies were similar in all five groups; however, significant differences occurred in nine systems. Heterozygosity level (mean ± SE) was lowest in the domestic group (0.119 ± 0.043) and ranged from 0.139 ± 0.043 to 0.166 ± 0.052 in the feral groups. Cluster analysis of genetic distances grouped the four feral groups together, but separate from the domestic group. Progeny from fish captured on Black Can Reef, Lake Michigan, in 1986 and 1988 were the most similar. A modified diallel mating design was developed to produce a composite brood stock from remnant feral and domestic fish. Pooled families from 1991 and 1992 diallel matings will be reared to maturity, then reciprocal crosses of the two year‐classes will be made to form the new composite Green Lake brood stock.

Wisconsin↗
USGS1991

Rapid classification of nuclear cataracts lake trout

To examine lake trout ( Salvelinus namaycush ) in the field for cataract and noncataract eye abnormalities, we developed a procedure with a circular 1.7‐power illuminated magnifying lamp. A box in which the lamp is mounted facilitates its transport and provides a support base for the lamp during use in the field. A classification system was developed for assigning nuclear cataracts to four stages based on cataract size as a percentage of the total cross‐sectional area of the lens. When the method was used by newly trained technicians to screen 200,000 fall lake trout fingerlings into cataract and noncataract groups, the error rates were 1.7 and 7.7%, respectively. A technician could examine up to 2,800 fingerlings, 1,300 yearlings, or 700 3‐year‐old fish per day.

Progressive Fish-Culturist↗
USGS1991

Effects of orally administered steroids on lake trout and Atlantic salmon

Lake trout ( Salvelinus namaycush ) and Atlantic salmon ( Salmo salar ) fed 30 mg β‐estradiol/kg of feed for 100 d from first feeding had liver and kidney pathology similar to but much less severe than that previously reported for rainbow trout ( Oncorhynchus mykiss ). Mortality was not affected. Both lake trout and Atlantic salmon treated with estradiol weighed significantly less than control fish at the end of the treatment period and at 200 d posttreatment. Testosterone‐treated fish of both species weighed less than control fish at the end of the treatment period. By day 200 posttreatment, testosterone‐treated and untreated lake trout weighed the same, but testosterone‐treated Atlantic salmon were heavier than control fish. Estradiol treatment produced an all‐female population of Atlantic salmon but not of lake trout. Testosterone at 5 mg/kg feed increased the ratio of males to females in both species.

Progressive Fish-Culturist↗