Mitochondrial DNA Diversity among Broodstocks of the Lake Trout, Salvelinus namaycush

1988 ◽  
Vol 45 (12) ◽  
pp. 2114-2122 ◽  
Author(s):  
Peter M. Grewe ◽  
Paul D. N. Hebert
Keyword(s):  
Mitochondrial Dna ◽  
Great Lakes ◽  
Lake Trout ◽  
Natural Populations ◽  
Restriction Enzymes ◽  
Salvelinus Namaycush ◽  
Brood Stock ◽  
Base Pairs ◽  
Specific Distribution ◽  
Western Great Lakes

Mitochondrial DNA was purified from 151 lake trout (Salvelinus namaycush) representing nine brood stocks along with an additional 30 fish from two natural populations. Eighteen restriction endonucleases were employed to analyze 126 brood stock fish. Two of these enzymes (Hind III and Bam HI) were used to examine the fish from the natural populations (Hare Island (Lake Superior) and North Knife Lake (Manitoba)) and the remaining brood stock samples from the Manitou (12 fish) and Seneca (13 fish) strains. The mitochondrial genome of the lake trout was 16 800 ± 200 base pairs in length. A single heteroplasmic individual was discovered in the Manitou strain. It contained two genomes, the less frequent of which was 20 base pairs shorter than the other. The 18 restriction enzymes resolved 13 mitochondrial clones which fell into three major groups. These clonal groups, which can be identified by their Bam HI restriction phenotypes, have a specific distribution: a western Great Lakes group, a central Great Lakes group, and an eastern Great Lakes group. Seven mitochondrial clones were unique to a particular stock. In addition there were dramatic shifts in the relative proportions of the six remaining mitochondrial clones among the brood stocks. These results indicate that mitochondrial DNA markers have great potential for the identification and management of lake trout strains.

Mitochondrial DNA Variation among Lake Trout (Salvelinus namaycush) Strains Stocked into Lake Ontario

1993 ◽  
Vol 50 (11) ◽  
pp. 2397-2403 ◽  
Author(s):  
Peter M. Grewe ◽  
Charles C. Krueger ◽  
Charles F. Aquadro ◽  
Eldredge Bermingham ◽  
Harold L. Kincaid ◽  
...  
Keyword(s):  
Mitochondrial Dna ◽  
Lake Trout ◽  
Lake Ontario ◽  
Restriction Enzymes ◽  
Salvelinus Namaycush ◽  
Purification Method ◽  
Dna Variation ◽  
Total Dna ◽  
Mixed Stock ◽  
Haplotype Information

Mitochondrial DNA (mtDNA) variation was examined in 492 fish representing six lake trout (Salvelinus namaycush) strains used for stocking and restoring populations in Lake Ontario. mtDNA was extracted from 432 fish by a total DNA isolation protocol (CTAB). mtDNA was also extracted from 60 additional fish using the purification method of CsCl ultracentrifugation. The more rapid CTAB protocol made feasible analysis of sample sizes (n ≥ 80 per strain) required as baseline data for future mixed-stock analysis (MSA). Restriction enzymes AvaI, BamHI, HinfI, and TaqI resolved seven mtDNA haplotypes and were used to characterize fish from each of six strains (Clearwater, Jenny, Killala, Manitou, Seneca, and Superior). Frequencies of these haplotypes were significantly different among the six strains (p < 0.001). Differences between haplotype frequencies of the Killala and Superior strains were striking and permit greater discrimination of these strains than allozyme data. The level of differentiation observed among strains indicates that mtDNA haplotype information will enhance the ability of MSA to determine the hatchery strains that serve as parents to lake trout fry collected from Lake Ontario.

Classification of Sea Lamprey (Petromyzon marinus) Attack Marks on Great Lakes Lake Trout (Salvelinus namaycush)

1980 ◽  
Vol 37 (11) ◽  
pp. 1989-2006 ◽  
Author(s):  
Everett Louis King Jr.
Keyword(s):  
Great Lakes ◽  
Lake Trout ◽  
Petromyzon Marinus ◽  
Attachment Site ◽  
Sea Lamprey ◽  
Salvelinus Namaycush ◽  
Oral Disc ◽  
Field Assessment ◽  
Sea Lampreys

Criteria for the classification of marks inflicted by sea lamprey (Petromyzon marinus) into nine categories were developed from laboratory studies in an attempt to refine the classification system used in field assessment work. These criteria were based on characteristics of the attachment site that could be identified under field conditions by unaided visual means and by touching the attachment site. Healing of these marks was somewhat variable and was influenced by the size of lamprey, duration of attachment, severity of the wound at lamprey detachment, season and water temperature, and by other less obvious factors. Even under laboratory conditions staging of some wounds was difficult, especially at low water temperatures. If these criteria are to be used effectively and with precision in the field, close examination of individual fish may be required. If the feeding and density of specific year-classes of sea lampreys are to be accurately assessed on an annual basis, close attention to the wound size (as it reflects the size of the lamprey's oral disc) and character of wounds on fish will be required as well as consideration of the season of the year in which they are observed.Key words: sea lamprey, attack marks, lake trout, Great Lakes

A Niche Definition for Lake Trout (Salvelinus namaycush) and Its Use to Identify Populations at Risk

1994 ◽  
Vol 51 (11) ◽  
pp. 2513-2519 ◽  
Author(s):  
Phil A. Ryan ◽  
Terry R. Marshall
Keyword(s):  
Oxygen Content ◽  
Lake Trout ◽  
Cold Water ◽  
Natural Populations ◽  
Oxygen Demand ◽  
Oxygen Depletion ◽  
Salvelinus Namaycush ◽  
Phosphorus Concentration ◽  
Suitable Habitat ◽  
Populations At Risk

Lake trout (Salvelinus namaycush) populations require cold water with high dissolved oxygen content for survival. We developed models that predict the availability of such habitat, using lake mean depth, which describes both the thermal regime and the initial oxygen reserves, and using a measure of primary productivity, which defines the subsequent oxygen demand of the sediments and water column. Measures of primary production include either phosphorus concentration, chlorophyll a concentration, or Secchi disk transparency. The models are presented as a series of seasonal oxygen depletion isopleths that predict the extent to which the oxygen content of thermally suitable habitat is lost during the period of thermal stratification. The presence or absence of native lake trout in lakes of northwestern Ontario superimposed on these graphs indicated that natural populations seldom occur in lakes in which the seasonal oxygen depletion exceeds 40%. This isopleth is a niche boundary in its representation of adverse temperature and oxygen conditions for lake trout. The delineation of this boundary permits the identification of lakes where lake trout populations could be seriously affected by cultural eutrophication, overfishing, or climate warming.

Effects of coancestry on accuracy of individual assignments to population of origin: examples using Great Lakes lake trout (Salvelinus namaycush)

Genetica ◽  
2006 ◽  
Vol 127 (1-3) ◽  
pp. 329-340 ◽  
Author(s):  
Bruno Guinand ◽  
Kim T. Scribner ◽  
Kevin S. Page ◽  
Kristi Filcek ◽  
Laura Main ◽  
...  
Keyword(s):  
Great Lakes ◽  
Lake Trout ◽  
Salvelinus Namaycush

Responses of Lake Trout (Salvelinus namaycush) to Harvesting, Stocking, and Lamprey Reduction

1980 ◽  
Vol 37 (11) ◽  
pp. 2133-2145 ◽  
Author(s):  
Carl J. Walters ◽  
Greg Steer ◽  
George Spangler
Keyword(s):  
Simple Model ◽  
Policy Analysis ◽  
Great Lakes ◽  
Population Regulation ◽  
Lake Trout ◽  
Normal Population ◽  
Lake Superior ◽  
Sea Lamprey ◽  
Salvelinus Namaycush ◽  
Density Dependent

Sustained yields, declines, and recovery of lake trout (Salvelinus namaycush) can be explained by a simple model that hypothesizes normal population regulation through density dependent body growth, coupled with depensatory lamprey mortality. The model indicates that either lamprey or fishing alone could have caused the Lake Superior decline, though they apparently operated in concert. The presence of depensatory lamprey mortality leads to a "cliff edge" in the system's dynamics, such that catastrophic changes may be repeated in the future. It is not unlikely that Lake Superior is on the verge of a second collapse. Options for dealing with potential disasters include conservative harvesting policies, development of more sensitive monitoring indicators, and modified stocking policies that may speed the coevolution of a viable lamprey/trout association.Key words: lake trout, sea lamprey, simulation, Great Lakes, policy analysis

Paenibacillus thiaminolyticus is not the cause of thiamine deficiency impeding lake trout (Salvelinus namaycush) recruitment in the Great Lakes

2012 ◽  
Vol 69 (6) ◽  
pp. 1056-1064 ◽  
Author(s):  
Catherine A. Richter ◽  
Allison N. Evans ◽  
Maureen K. Wright-Osment ◽  
James L. Zajicek ◽  
Scott A. Heppell ◽  
...  
Keyword(s):  
Great Lakes ◽  
Thiamine Deficiency ◽  
Lake Trout ◽  
Bacterial Species ◽  
Primary Source ◽  
Salvelinus Namaycush ◽  
Trophic Levels ◽  
Thiaminase I ◽  
Global Concern ◽  
Paenibacillus Thiaminolyticus

Thiamine (vitamin B1) deficiency is a global concern affecting wildlife, livestock, and humans. In Great Lakes salmonines, thiamine deficiency causes embryo mortality and is an impediment to restoration of native lake trout ( Salvelinus namaycush ) stocks. Thiamine deficiency in fish may result from a diet of prey with high levels of thiaminase I. The discoveries that the bacterial species Paenibacillus thiaminolyticus produces thiaminase I, is found in viscera of thiaminase-containing prey fish, and causes mortality when fed to lake trout in the laboratory provided circumstantial evidence implicating P. thiaminolyticus. This study quantified the contribution of P. thiaminolyticus to the total thiaminase I activity in multiple trophic levels of Great Lakes food webs. Unexpectedly, no relationship between thiaminase activity and either the amount of P. thiaminolyticus thiaminase I protein or the abundance of P. thiaminolyticus cells was found. These results demonstrate that P. thiaminolyticus is not the primary source of thiaminase activity affecting Great Lakes salmonines and calls into question the long-standing assumption that P. thiaminolyticus is the source of thiaminase in other wild and domestic animals.

New insight into the spawning behavior of lake trout, Salvelinus namaycush, from a recovering population in the Laurentian Great Lakes

2014 ◽  
Vol 98 (1) ◽  
pp. 173-181 ◽  
Author(s):  
T. R. Binder ◽  
H. T. Thompson ◽  
A. M. Muir ◽  
S. C. Riley ◽  
J. E. Marsden ◽  
...  
Keyword(s):  
Great Lakes ◽  
Lake Trout ◽  
Salvelinus Namaycush ◽  
Laurentian Great Lakes ◽  
Spawning Behavior ◽  
Insight Into

Phylogeography and postglacial dispersal of lake trout (Salvelinus namaycush) in North America

1998 ◽  
Vol 55 (4) ◽  
pp. 1010-1024 ◽  
Author(s):  
Christopher C Wilson ◽  
Paul DN Hebert
Keyword(s):  
Lake Trout ◽  
Restriction Enzymes ◽  
Glacial Refugia ◽  
Salvelinus Namaycush ◽  
Secondary Contact ◽  
Freshwater Species ◽  
Long Distance ◽  
Proglacial Lakes ◽  
Mtdna Lineages ◽  
Mtdna Diversity

We used restriction fragment length polymorphism (RFLP) analysis of mitochondrial DNA (mtDNA) diversity to assess the complex postglacial history of lake trout (Salvelinus namaycush) and test existing dispersal hypotheses. A pilot survey with 30 restriction enzymes was carried out on lake trout from 16 geographically representative populations to determine phylogenetically informative characters. Subsequent screening of 1416 lake trout from 93 populations across the species' range with nine variable restriction enzymes showed that lake trout from at least five glacial refugia contributed to extant populations. Three major mtDNA lineages were observed, with sufficient differences to suggest their divergence during the mid-Pleistocene. Geographic and genetic differences within two lineages suggested further vicariant divergence caused by Wisconsinan glacial advances. In contrast with more southern freshwater species, no correlation was observed between the geographic proximity of glacial refugia and relatedness of mtDNA lineages. Current distributions of refugial lineages are readily explained by consideration of timing and connections of proglacial lakes. These lakes facilitated large-scale dispersal from multiple refugia, particularly enabling long-distance dispersal from the Mississippian and northwestern refugia. Proglacial lakes also enabled extensive secondary contact among refugial groups, resulting in high levels of intrapopulation mtDNA diversity within their former boundaries.

Taxonomy of a Swimbladder Nematode, Cystidicola stigmatura (Leidy), and Evidence of its Decline in the Great Lakes

1983 ◽  
Vol 40 (5) ◽  
pp. 643-647 ◽  
Author(s):  
Geoff A. Black
Keyword(s):  
Great Lakes ◽  
Lake Trout ◽  
Salvelinus Namaycush ◽  
Valid Species ◽  
Museum Specimens

Cystidicola stigmatura (Leidy, 1886) Ward and Magath, 1917 is considered a valid species after examination of specimens from Leidy's collection. Cystidicola cristivomeri White, 1941 is considered a synonym of C. stigmatura. Cystidicola stigmatura is distinguished from the only other species in the genus, namely C. farionis Fischer, 1798, by the presence of lateral lobes on the eggs rather than filaments. A neotype of F. stigmatura is designated. Cystidicola stigmatura has not been found in fishes in the Great Lakes since 1925. The parasite was found in museum specimens of lake trout (Salvelinus namaycush) collected before 1925, suggesting that the species became rare or disappeared with the decline of lake trout in these lakes.

Sign in / Sign up

Export Citation Format

Share Document