Life history, distribution, and production of Diporeia near the Keweenaw Peninsula Lake Superior

In the Report of the Entomologist and Botanist to the Dominion Experimental Farms for 1905, at pages 179 and 180, considerable space is given to a discussion of an outbreak of a large noctuid caterpillar, which appeared in considerable numbers in Canada during 1905. Complaints of injury by this insect were received from a wide area, extending from Nova Scotia as far west as Lake Superior. During July many kinds of plants in gardens were attacked by smooth cutworm-like caterpillas, which when small were greenish in colour, having the body divided into two equal areas above and below the spiracles by a wide black stigmatal band.

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Comparison of growth physiology, morphology, and smolt indicators in juvenile Lake Superior brook trout (Salvelinus fontinalis) strains in reference to life history variation

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f2012-083 ◽

2012 ◽

Vol 69 (10) ◽

pp. 1596-1609 ◽

Cited By ~ 3

Author(s):

Carla A.V. Serfas ◽

Anna Varian ◽

Rachel Holman ◽

Lindsey M. Watch ◽

Jesse Karner ◽

...

Keyword(s):

Life History ◽

Brook Trout ◽

Salvelinus Fontinalis ◽

Lake Superior ◽

Morphological Variability ◽

Life History Strategy ◽

Growth Potential ◽

Relative Mass ◽

Life History Variation ◽

Rate Condition

Lake Superior supports fluvial, adfluvial, and lacustrine populations of brook trout ( Salvelinus fontinalis ). Adfluvial and lacustrine populations (termed coasters) are known for their large size and are coveted by anglers; however, little is known about their migratory habits or physiology. This study examined physiology and morphology of age 1+ lacustrine, adfluvial, and fluvial strains of brook trout in a laboratory setting. All strains in the study grew; however, there were no differences in growth rate, condition, relative mass, morphology, white muscle metabolic enzymes, or gill Na+,K+-ATPase that clearly associated with putative life history strategy. Both thyroxine and triiodothyronine varied over the study period, and the fluvial (resident) strain consistently showed lower thyroid hormone levels than the three coaster strains. We conclude that the populations compared differed at the strain level, but do not show physiological or morphological variability that clearly associates with life history strategy; the exception was that populations demonstrating the coaster phenotype had increased concentrations of plasma thyroid hormones, which may be linked to growth potential or other coaster-related characteristics such as migration.

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Abundance and Life History of Mysis relicta in the St. Lawrence Great Lakes

Journal of the Fisheries Research Board of Canada ◽

10.1139/f74-051 ◽

1974 ◽

Vol 31 (3) ◽

pp. 319-325 ◽

Cited By ~ 41

Author(s):

G. F. Carpenter ◽

E. L. Mansey ◽

N. H. F. Watson

Keyword(s):

Life History ◽

Generation Time ◽

Lake Superior ◽

Life Cycles ◽

Lake Huron ◽

Summer Period ◽

Mysis Relicta ◽

Frequency Distributions ◽

History Of ◽

Major Period

In sampling on lakes Ontario, Erie, and Superior during three cruises from spring to fall, and on Lake Huron during eight cruises, Mysis relicta was generally not taken or not abundant in waters less than 25 m in depth. Its abundance appeared to increase with depth at least up to 200 m. Populations appeared to be concentrated in waters 125–200 m deep during summer and more dispersed during spring and fall. Highest numbers were found in Lake Superior, followed by lakes Ontario and Huron. A small localized population was found in the deep eastern part of Lake Erie.Size-frequency distributions from the various cruises on lakes Superior, Huron, and Ontario indicated differences in life cycles of the mysid in the three lakes. In Lake Superior there was one major period of recruitment, from February to July, and the generation time appeared to be 2 yr. In lakes Huron and Ontario recruitment appeared to occur from February to August and to be separated into a winter and a summer period; each of the generations appeared to mature in 18 mo.

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The Benthic Nepheloid Layer (BNL) North of the Keweenaw Peninsula in Lake Superior: Composition, Dynamics, and Role in Sediment Transport

Journal of Great Lakes Research ◽

10.1016/s0380-1330(04)70382-2 ◽

2004 ◽

Vol 30 ◽

pp. 133-146 ◽

Cited By ~ 7

Author(s):

Noel R. Urban ◽

J. Jeong ◽

Yingtao Chai

Keyword(s):

Sediment Transport ◽

Lake Superior ◽

Nepheloid Layer ◽

Keweenaw Peninsula ◽

Benthic Nepheloid Layer

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Changing Water Levels in Lake Superior, MI (USA) Impact Periphytic Diatom Assemblages in the Keweenaw Peninsula

Water ◽

10.3390/w13030253 ◽

2021 ◽

Vol 13 (3) ◽

pp. 253

Author(s):

M. Megan Woller-Skar ◽

Alexandra Locher ◽

Ellen Audia ◽

Evan W. Thomas

Keyword(s):

Water Level ◽

Surface Area ◽

Lake Superior ◽

Water Levels ◽

Ecological Processes ◽

Periphyton Community ◽

Water Level Changes ◽

Community Assemblages ◽

Keweenaw Peninsula ◽

The Impact

Predicted climate-induced changes in the Great Lakes include increased variability in water levels, which may shift periphyton habitat. Our goal was to determine the impacts of water level changes in Lake Superior on the periphyton community assemblages in the Keweenaw Peninsula with different surface geology. At three sites, we identified periphyton assemblages as a function of depth, determined surface area of periphyton habitat using high resolution bathymetry, and estimated the impact of water level changes in Lake Superior on periphyton habitat. Our results suggest that substrate geology influences periphyton community assemblages in the Keweenaw Peninsula. Using predicted changes in water levels, we found that a decrease in levels of 0.63 m resulted in a loss of available surface area for periphyton habitat by 600 to 3000 m2 per 100 m of shoreline with slopes ranging 2 to 9°. If water levels rise, the surface area of substrate will increase by 150 to 370 m2 per 100 m of shoreline, as the slopes above the lake levels are steeper (8–20°). Since periphyton communities vary per site, changes in the surface area of the substrate will likely result in a shift in species composition, which could alter the structure of aquatic food webs and ecological processes.

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