The transmission, life span, and population biology of Cystidicola cristivomeri White, 1941 (Nematoda: Habronematoidea) in char, Salvelinus spp.

1981 ◽  
Vol 59 (3) ◽  
pp. 498-509 ◽  
Author(s):  
Geoff A. Black ◽  
Murray W. Lankester
Keyword(s):  
Population Biology ◽  
Lake Trout ◽  
Salvelinus Namaycush ◽  
Mature Female ◽  
Arctic Char ◽  
Mysis Relicta ◽  
Northwestern Ontario ◽  
Third Stage ◽  
Paratenic Hosts ◽  
Fish Hosts

The population biology of Cystidicola cristivomeri White, 1941 was investigated in lake trout, Salvelinus namaycush, in three lakes in northwestern Ontario and in arctic char, S. alpinus, in Gaviafaeces Lake, Northwest Territories. Young lake trout fed selectively on large Mysis relicta, which were more frequently infected with C. cristivomeri (up to 5.1%) than small mysids. Pontoporeia affinis was not a suitable intermediate host in nature and there was no evidence that fish paratenic hosts were important in transmitting this nematode to lake trout.Most C. cristivomeri appear to live at least 10 years in naturally infected lake trout and arctic char. In these fishes the size of C. cristivomeri infrapopulations is determined by several factors. The feeding preferences of fish hosts and the availability of forage in individual lakes determine the extent and duration of feeding on M. relicta. Each naturally infected mysid contains only one third-stage C. cristivomeri larva. In the swim bladder of infected fishes, the proportion of female C. cristivomeri reaching sexual maturity and the length of females is inversely related to the total number of worms present. The length of mature female worms, in turn, is positively correlated with the rate at which they produce eggs. As a result, the egg output of C. cristivomeri at the infrapopulation level is density dependent.

Occurrence of the Acanthocephalan Echinorhynchus leidyi (Van Cleave, 1924) in Mysis relicta

1983 ◽  
Vol 61 (2) ◽  
pp. 460-462 ◽  
Author(s):  
S. B. Prychitko ◽  
R. W. Nero
Keyword(s):  
Intermediate Host ◽  
Definitive Host ◽  
Lake Trout ◽  
Parasite Prevalence ◽  
Salvelinus Namaycush ◽  
Mysis Relicta ◽  
Northwestern Ontario

Mysis relicta has been identified as an intermediate host of the acanthocephalan Echinorhynchus leidyi (Van Cleave, 1924) Golvan, 1969 in four of eight lakes examined in northwestern Ontario. Parasite prevalence in Mysis relicta ranged from less than 1 to 3.6%. Lake trout (Salvelinus namaycush) are a common definitive host.

Multiple Trophic Level Structuring in Salvelinus–Coregonus Assemblages in Boreal Forest Lakes

1993 ◽  
Vol 50 (7) ◽  
pp. 1442-1455 ◽  
Author(s):  
Edward A. Trippel ◽  
F. William H. Beamish
Keyword(s):  
Body Size ◽  
Lake Trout ◽  
Zooplankton Community ◽  
Salvelinus Namaycush ◽  
High Conductivity ◽  
Top Down ◽  
Mysis Relicta ◽  
Northwestern Ontario ◽  
Coregonus Artedi ◽  
Forest Lakes

Hypolimnetic trophic interactions were examined among lake trout (Salvelinus namaycush), cisco (Coregonus artedi), zooplankton, and macroinvertebrates in six northwestern Ontario lakes varying sevenfold in conductivity. Faster growth and larger body size of lake trout in high-conductivity lakes were associated with larger meal sizes, earlier entry of cisco into their diet, and consumption of relatively few, large-bodied prey. Cisco preyed on zooplankton and macroinvertebrates. Cisco were abundant, large bodied, and fast growing in high-conductivity lakes. In one low-conductivity lake (Greenwich Lake), lake trout were 12 times as abundant as cisco whereas in all other lakes, lake trout to cisco ratios were ~ 1:1 or less regardless of conductivity. In Greenwich Lake, lake trout consumed large quantities of age-0 cisco and Mysis relicta, which was associated with "top-down" trophic structuring. Food web analyses strongly suggest that in Greenwich Lake the high abundance of piscivores resulted directly in a low abundance of planktivores and indirectly in a large-bodied zooplankton community and planktivores with rapid growth rates.

Land water linkages: influences of riparian deforestation on lake thermocline depth and possible consequences for cold stenotherms

1997 ◽  
Vol 54 (6) ◽  
pp. 1299-1305 ◽  
Author(s):  
Robert France
Keyword(s):  
Thermal Stratification ◽  
Lake Trout ◽  
Salvelinus Namaycush ◽  
Thermocline Depth ◽  
Experimental Lakes Area ◽  
Northwestern Ontario ◽  
Riparian Trees ◽  
Tree Removal ◽  
Riparian Tree ◽  
Land Water

The purpose of the present study was to determine if riparian deforestation would expose lake surfaces to stronger winds and therefore bring about deepening of thermoclines and resulting habitat losses for cold stenotherms such as lake trout (Salvelinus namaycush). Removal of protective riparian trees through wind blowdown and two wildfires was found to triple the overwater windspeeds and produce thermocline deepening in two lakes at the Experimental Lakes Area. A survey of thermal stratification patterns in 63 northwestern Ontario lakes showed that lakes around which riparian trees had been removed a decade before through either clearcutting or by a wildfire were found to have thermocline depths over 2 m deeper per unit fetch length compared with lakes surrounded by mature forests. Riparian tree removal will therefore exacerbate hypolimnion habitat losses for cold stenotherms that have already been documented to be occurring as a result of lake acidification, eutrophication, and climate warming.

Migration and development of swim-bladder nematodes, Cystidicola spp. (Habronematoidea), in their definitive hosts

1980 ◽  
Vol 58 (11) ◽  
pp. 1997-2005 ◽  
Author(s):  
Geoff A. Black ◽  
Murray W. Lankester
Keyword(s):  
Rainbow Trout ◽  
Lake Trout ◽  
Distinct Species ◽  
Salmo Gairdneri ◽  
Swim Bladder ◽  
Coregonus Clupeaformis ◽  
Lake Whitefish ◽  
Northwestern Ontario ◽  
Third Stage ◽  
Migration And Development

Third-stage larvae of Cystidicola cristivomeri White, 1941, and C. farionis Fischer, 1798, migrated directly via the pneumatic duct to the swim bladder of lake trout, Salvelinus namaycush, and rainbow trout, Salmo gairdneri, respectively. Larvae reached the swim bladder as early as 16 h after fish were infected using a stomach tube. At 4–10 °C, mature male and female C. cristivomeri and C. farionis were first recovered 67 and 210 days, and 112 and 235 days, respectively, after infection. Cystidicola cristivomeri is probably long-lived; there was no evidence that any died in lake trout infected for up to 600 days.Large numbers of third-stage cystidicolid larvae accumulated without maturing in the swim bladder of naturally infected lake whitefish, Coregonus clupeaformis, from Lake Nipigon, northwestern Ontario. When given to rainbow trout, these larvae matured and the adult nematodes were identical to C. farionis. These results suggest that the swim-bladder nematode that matures in lake whitefish is a distinct species.

Origin, Distribution, and Postglacial Dispersal of a Swimbladder Nematode, Cystidicola stigmatura

1983 ◽  
Vol 40 (8) ◽  
pp. 1244-1253 ◽  
Author(s):  
Geoff A. Black
Keyword(s):  
Lake Michigan ◽  
Lake Trout ◽  
Arctic Char ◽  
The Arctic ◽  
Glacial Lake ◽  
Glacial Refugium ◽  
Drainage Basins ◽  
Northwestern Ontario ◽  
River Region ◽  
St Lawrence River

New distributional records indicate that Cystidicola stigmatura occurs in lake trout (Salvelinus namaycush) and Arctic char (S. alpinus) in the Great Lakes and St. Lawrence River drainage basins, in lakes along an arc extending from northwestern Ontario to Great Bear Lake and into the Canadian Arctic Archipelago but not elsewhere. This distribution can be explained by the parasite's probable postglacial history. I hypothesize that the nematode survived in only one glacial refugium. During deglaciation the parasite probably dispersed with lake trout from its refugium in the upper Mississippi River region into the Lake Michigan basin. Confluence of glacial waters would have given the nematode access to the drainage basins of Lakes Huron, Erie, and Ontario. Invasion of the St. Lawrence River basin occurred during a postglacial connection with the Lake Ontario basin. Dispersal from the Lake Huron basin was via glacial Lake Algonquin and later via glacial Lake Barlow–Ojibway and gave rise to present populations in eastern Ontario and western Quebec. Northward dispersal was probably via the glacial waters of the Lake Michigan–Lake Superior basin through glacial Lakes Agassiz, McConnell, and Coppermine to the Arctic Ocean. Arctic char would have first acquired the parasite at this time. Extant parasite populations along this dispersal route occur in Minnesota, northwestern Ontario, Manitoba, Saskatchewan, and the Northwest Territories. Invasion of the Arctic Archipelago has been with anadromous fishes. The apparently restricted preglacial distribution of the nematode and recent history of its intermediate host (Mysis relicta) in freshwater suggests that C. stigmatura may have arisen as a species during the last glaciation.

Pelagic distribution of lake trout (Salvelinus namaycush) in small Canadian Shield lakes with respect to temperature, dissolved oxygen, and light

1998 ◽  
Vol 55 (1) ◽  
pp. 170-179 ◽  
Author(s):  
Todd J Sellers ◽  
Brian R Parker ◽  
David W Schindler ◽  
William M Tonn
Keyword(s):  
Light Intensity ◽  
Dissolved Oxygen ◽  
Lake Trout ◽  
Salvelinus Namaycush ◽  
Canadian Shield ◽  
Small Lakes ◽  
Experimental Lakes Area ◽  
Northwestern Ontario ◽  
Oxygenated Water ◽  
Shield Lakes

The distribution of lake trout (Salvelinus namaycush) with respect to water temperature, dissolved oxygen, and light intensity was surveyed in three small Canadian Shield lakes at the Experimental Lakes Area, northwestern Ontario. Based on hydroacoustic and gillnet surveys, there was considerable variation among lakes in temperatures occupied by lake trout during the summer. During the day, lake trout were concentrated at 4-8°C in Lake 375, broadly distributed from 6 to 15°C in Lake 442, and concentrated in the epilimnion at 19°C in Lake 468. At night, lake trout in all lakes occupied epilimnetic waters at 19-20°C. Lake trout inhabited highly oxygenated water, with 75-90% of fish at >6 mg dissolved oxygen ·L-1 throughout the spring and summer in all three lakes. Light intensity did not affect lake trout distribution in Lake 468 but may have contributed to lake trout daytime descent into cool waters in Lakes 375 and 442. We suggest that previously assumed niche boundaries of lake trout do not adequately describe critical habitat for the species in small lakes, the same lakes that are likely most sensitive to erosion of such habitat.

Anadromy in Arctic populations of lake trout (Salvelinus namaycush): otolith microchemistry, stable isotopes, and comparisons with Arctic char (Salvelinus alpinus)

2010 ◽  
Vol 67 (5) ◽  
pp. 842-853 ◽  
Author(s):  
Heidi K. Swanson ◽  
Karen A. Kidd ◽  
John A. Babaluk ◽  
Rick J. Wastle ◽  
Panseok P. Yang ◽  
...  
Keyword(s):  
Lake Trout ◽  
Salvelinus Alpinus ◽  
Salt Water ◽  
Salvelinus Namaycush ◽  
Otolith Microchemistry ◽  
Scientific Data ◽  
Arctic Char ◽  
Arctic Lakes ◽  
Size Dependent ◽  
The Family

In the family Salmonidae, lake trout ( Salvelinus namaycush ) are considered the least tolerant of salt water. There are, however, sporadic reports of lake trout in coastal, brackish habitats in the Canadian Arctic. Otolith microchemistry analyses conducted on lake trout and Arctic char ( Salvelinus alpinus ) from four Arctic lakes in the West Kitikmeot region of Nunavut, Canada, revealed that 37 of 135 (27%) lake trout made annual marine migrations. Anadromous lake trout were in significantly better condition (K = 1.17) and had significantly higher C:N ratios (3.71) than resident lake trout (K = 1.05 and C:N = 3.34). Anadromous lake trout also had significantly higher δ15N (mean = 16.4‰), δ13C (mean = –22.3‰), and δ34S (mean = 13.43‰) isotope ratios than resident lake trout (means = 12.84‰, –26.21‰, and 1.93‰ for δ15N, δ13C, and δ34S, respectively); results were similar for Arctic char and agree with results from previous studies. Mean age of first migration for lake trout was 13 years, which was significantly older than that for Arctic char (5 years). This could be a reflection of size-dependent salinity tolerance in lake trout, but further research is required. These are the first detailed scientific data documenting anadromy in lake trout.

Performance of temperature and dissolved oxygen criteria to predict habitat use by lake trout (Salvelinus namaycush)This paper is part of the series “Forty Years of Aquatic Research at the Experimental Lakes Area”.

2009 ◽  
Vol 66 (11) ◽  
pp. 2011-2023 ◽  
Author(s):  
John M. Plumb ◽  
Paul J. Blanchfield
Keyword(s):  
Habitat Use ◽  
Dissolved Oxygen ◽  
Thermal Stratification ◽  
Lake Trout ◽  
Salvelinus Namaycush ◽  
Experimental Lakes Area ◽  
Lake Volume ◽  
Northwestern Ontario ◽  
Environmental Extremes

We compared theoretical habitat volumes, determined from traditional combinations of temperature and dissolved oxygen concentration (DO) boundaries, with in situ habitat use by acoustically tagged lake trout ( Salvelinus namaycush ). The widely used criteria of 8–12 °C underestimated lake trout habitat use by 68%–80%. Instead, combined temperature (<12 or 15 °C) and DO (>4 or 6 mg·L–1) criteria most closely matched lake trout habitat use, had a similar seasonal trend as the tagged fish, suggested modest reductions (5% of total lake volume) in habitat during a warmer year, and performed best when the constraints of temperature and DO were most limiting. All data were collected in a small boreal shield lake (27 ha, zmax = 21 m) at the Experimental Lakes Area in northwestern Ontario, Canada, during two contrasting periods of thermal stratification (2003: warmer and longer; 2004: cooler and shorter), providing an assessment of observed and theoretical habitat volumes over current environmental extremes.

Survival and Development of Lake Trout (Salvelinus namaycush) embryos in an Acidified Lake in Northwestern Ontario

1990 ◽  
Vol 47 (2) ◽  
pp. 236-243 ◽  
Author(s):  
L. C. Mohr ◽  
K. H. Mills ◽  
J. F. Klaverkamp
Keyword(s):  
Lake Trout ◽  
Salvelinus Namaycush ◽  
Experimental Lakes Area ◽  
Embryo Survival ◽  
Embryo Mortality ◽  
Recruitment Failure ◽  
Northwestern Ontario ◽  
Survival And Development ◽  
Population Recruitment ◽  
Experimental Acidification

Survival and development of lake trout (Salvelinus namaycush) embryos from L223 in the Experimental Lakes Area, northwestern Ontario, were evaluated from 1979 (pH 5.6) to 1982 (pH 5.1). Survival of L223 embryos was not significantly correlated to lake pH during experimental acidification. Also, embryo mortality in L223 was not significantly different from that of lake trout embryos in two reference lakes, L224 and L468. Survival of L223 embryos was not improved when they were incubated in nonacidified lakes. Embryo mortality was highest in all lakes (33–81%) within 15 d of fertilization. Mortality was negligible from Day 15 until the termination of the seasonal observations (Day 120 or 150). High variability in embryo survival existed between individual females within a single lake. The mean size of eggs from L223 lake trout decreased significantly from 1979 to 1982. Recruitment failures occurred in L223 from 1980 to 1982. We hypothesize that lake trout recruitment failure in L223 occurred between the posthatching period (spring) and actual recruitment into the population as young-of-the-year (fall) and that embryo mortality in this lake was not critical to population recruitment.

Population Biology of Lake Trout (Salvelinus namaycush) of Lake Superior before 1950

1971 ◽  
Vol 28 (1) ◽  
pp. 65-71 ◽  
Author(s):  
Gary T. Sakagawa ◽  
Richard L. Pycha
Keyword(s):  
Mortality Rate ◽  
Population Biology ◽  
Lake Trout ◽  
Lake Superior ◽  
Indirect Evidence ◽  
Total Mortality ◽  
Growth Yield ◽  
Salvelinus Namaycush ◽  
Natural Mortality ◽  
Trout Population

Scale samples collected in 1948 were used to estimate the instantaneous total mortality rate (0.70) and growth for lake trout (Salvelinus namaycush) in Lake Superior before the population had been significantly reduced by the sea lamprey (Petromyzon marinus). Indirect evidence indicates that the instantaneous natural mortality rate was probably 0.10–0.25. The Ricker model was used to calculate yield per recruitment, which varied with natural mortality and growth. Natural mortality was more critical than growth; yield per recruitment increased 183.3% with a 60% decrease in instantaneous natural mortality (from 0.25 to 0.10). For the prelamprey lake trout population the yield per recruitment was about 12–34 lb; the recruitment of about 3.6–10.1 million lake trout of age 1.5 resulted in an annual commercial production of 4 million lb.

Sign in / Sign up

Export Citation Format

Share Document