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Thomas A. Edsall

Publications and source records attributed to Thomas A. Edsall.

53 records · Page 3Linked to original sources
USGS1988

The St. Clair River and Lake St. Clair, Michigan: an ecological profile

The St. Clair River and Lake St. Clair form a part of the connecting channel system between Lake Huron and Lake Erie. This report synthesizes existing information on the ecological structure and function of this ecosystem. Chapters include descriptions of climatology, hydrology, and geology of the region; biological characteristics; ecological relationships; and commercial and recreational uses, as well as discussions of management considerations and issues. The St. Clair system provides valuable habitat for migratory waterfowl and fish spawning and nurseries, and contains some of the most extensive emergent wetlands in the region. The system is used for navigation, municipal and industrial waste disposal, recreational boating, fishing and waterfowl hunting. Allowing for multiple human uses while maintaining important waterfowl and fish populations is the greatest challenge facing managers of this system.

Biological Report↗
USGS1988

The Detroit River, Michigan: an ecological profile

A part of the connecting channel system between Lake Huron and Lake Erie, the Detroit River forms an integral link between the two lakes for both humans and biological resources such as fish, nutrients, and plant detritus. This profile summarizes existing scientific information on the ecological structure and functioning of this ecosystem. Topics include the geological history of the region, climatic influences, river hydrology, lower trophic-level biotic components, native and introduced fishes, waterfowl use, ecological interrelationships, commercial and recreational uses of the river, and current management issues. Despite urbanization, the river still supports diverse fish, waterfowl, and benthic populations. Management issues include sewer overflows; maintenance dredging for navigation and port activities; industrial discharges of potentially hazardous materials; and wetland, fishery, and waterfowl protection and enhancement.

Biological Report↗
USGS1988

Using side scan sonar data in a geographic information system to locate and display lake trout spawning habitat in the Great Lakes

The National Fisheries Research Center-Great Lakes of the U.S. Fish and Wildlife Service has extensively used a side scan sonar to survey and pinpoint lake trout spawning grounds in the Great Lakes. The Geographic Information System (GIS) of the National Ecology Research Center produced maps from the side scan sonar data showing the exact location of the spawning grounds; this will enable current stocking programs to be carried out at those locations. These maps show the geographic position (latitude and longitude) of both the color-coded primary substrate types and the secondary substrate types, which are denoted by overstrikes. The maps must be supplemented with a Loran-C navigation grid for field use. The maps are proving useful to fishery managers by locating lake trout stocking areas in Lakes Michigan and Huron, as well as to researchers who investigate habitat quality on lake trout spawning grounds.

Conference Paper↗
USGS1985

Growth of submersed macrophyte communities in the St. Clair - Detroit River system between Lake Huron and Lake Erie

Growth of submersed aquatic macrophytes was determined from observation and on the basis of biomass of samples collected from April to November 1978 at seven study sites in a major river system of the Great Lakes, the St. Clair – Detroit river system between Lake Huron and Lake Erie. Growth usually began between April and June, peaked between July and October, and decreased by late November. Maximum biomass at six of the seven sites (118–427 g dry weight m −2 ) was similar or greater than that reported in other rivers at similar latitudes. Seasonal growth of the abundant taxa followed one of three seasonal patterns at each study site: one dominant taxon grew alone; codominant taxa grew sympatrically without species succession; and codominant taxa grew sympatrically with species succession. Differences in growth and seasonal succession of some taxa were apparently caused by the presence or absence of overwintering plant material, competition, and life-cycle differences.

Canadian Journal of Botany↗
USGS1976

Temperature tolerance of young-of-the-year lake whitefish, Coregonus clupeaformis

The ultimate upper lethal temperature of young-of-the-year lake whitefish, Coregonus clupeaformis , was 26.65 C; this value is closely similar to that reported for yearling bloaters, Coregonus hoyi (26.75 C) and young-of-the-year lake herring, Coregonus artedii (26.0 C).

Journal of the Fisheries Research Board of Canada↗
USGS1974

Effect of acclimation temperature and heat shock on vulnerability of fry of lake whitefish ( Coregonus clupeaformis ) to predation

Fry of lake whitefish ( Coregonus clupeaformis ) acclimated to 10, 15, and 18 C were exposed to temperatures of 24.5, 25, and 28 C for 1 min and then immediately returned to water at their acclimation temperature, in test tanks containing yearling yellow perch ( Perca flavescens ). The number of attacks on the fry and the number captured and eaten in 30 min were recorded in separate tests of shocked and unshocked (control) whitefish.Significantly more whitefish were captured per attack (data for shocked and unshocked fry combined) at 15 and 18 C than at 10 C; and shocked fry were significantly more vulnerable to capture by the perch than were unshocked controls.

Journal of the Fisheries Research Board of Canada↗
USGS1970

Temperature tolerance of bloater ( Coregonus hoyi )

Juvenile and young adult bloaters ( Coregonus hoyi ) were tested for tolerance to high temperatures. The ultimate upper lethal temperature of juvenile bloaters (26.75 C) appeared to be slightly higher than that of young adult bloaters, but was similar to that of juvenile ciscoes, Coregonus artedii (26.0 C), the only other North American coregonine for which a detailed description of temperature tolerance has been published.Regression equations are given that permit estimation of the thermal tolerance when the lethal temperatures are incompletely known. The estimated thermal tolerance of juvenile bloaters (617 units) was slightly less than that of the brook trout ( Salvelinus fontinalis ; 625 units), but was higher than that of other Salmonidae.

Journal of the Fisheries Research Board of Canada↗
USGS1970

The effect of temperature on the rate of development and survival of alewife eggs and larvae

Eggs from Lake Michigan alewives (Alosa pseudoharengus) were incubated at 79 different temperatures from 42.1 to 87.0 F. Hatching occurred at 44.4-84.9 F and was optimum (38% hatched) at about 64 F. Incubation time varied from 15 days at 45 F to 3.7 days at 70 F and 2.1 days at 84 F. Time from start to finish of hatching ranged from 13 days at about 46 F to 2-3 days at 68-70 F and 1-2 days at 80-84 F. Survival of unfed larvae held at incubation temperatures increased from 3.8 days at 51 F to 7.6 days at 58-59 F and then decreased to 2.4 days at 80-82 F.

Transactions of the American Fisheries Society↗
USGS1970

Temperature tolerance of young-of-the-year cisco, Coregonus artedii

Young-of-the-year ciscoes (Coregonus artedii) acclimated to 2, 5, 10, 20 and 25 C and tested for tolerance to high and low temperatures provide the first detailed description of the thermal tolerance of coregonids in North America. The upper ultimate lethal temperature of the young ciscoes was 26 C (6 C higher than the maximum sustained temperature tolerated by adult ciscoes in nature) and the ultimate lower lethal temperature approached 0 C (near that commonly tolerated in nature by adult ciscoes). The temperature of 26 C is slightly higher than the lowest ultimate upper lethal temperature recorded for North American freshwater fishes; however, published information on the depth distributions of fishes in the Great Lakes suggests that some of the other coregonids may be less tolerant of high temperatures than the cisco.

Transactions of the American Fisheries Society↗
USGS1970

A hermaphroditic coregonine from Lake Michigan

Hermaphroditism is relatively rare among the Salmonidae (See Atz, 1964 for a comprehensive review) and has never been reported for coregonine fishes. Recent examination of a collection of coregonines at the Great Lakes Fishery Laboratory disclosed a hermaphroditic bloater( Coregonus hoyi ). The fish was captured in a gill net set at 50 fathoms on the bottom of Lake Michigan approximately 7.5 miles NNW of Frankfort, Michigan, on November 2, 1955. The fish had a normal rate of growth and was 234 mm long and in its 5th year of life; it was normal in external appearance but was easily identified as a hermaphrodite by gross examination of its gonads

Transactions of the American Fisheries Society↗
USGS1968

Two hermaphroditic alewives from Lake Michigan

Hermaphroditism has been reported frequently among many of the Clupeidae, but only one account of hermaphroditism has been published for the alewife, Alosa pseudoharengus. Rothschild discovered four hermaphroditic alewives among 444 fish he examined from Cayuga Lake, New York. We recently collected two hermaphroditic alewives from Lake Michigan. Both fish were normal in external appearance but were easily identified as hermaphrodites by gross examination of their gonads. The first hermaphrodite (177 mm T.L.) was discovered among several hundred normal adult alewives captured in early July 1965 in the Kalamazoo River about one mile upstream from Lake Michigan. The second hermaphroditic alewife (152 mm T.L.) was obtained from a sample of 160 adult alewives captured in Lake Michigan near the mouth of the Kalamazoo River in mid-April 1966.

Copeia↗
USGS1967

Biology of the freshwater drum in western Lake Erie

Information on the biology of the freshwater drum or sheepshead ( Aplodinotus grunniens ) was collected in Lake Erie during a fishery and limnological study made by the Bureau of Commercial Fisheries in 1957 and 1958. Growth of the sheepshead in 1958 was slower than in 1927, and slower than the growth in most other waters. Males and females grew at the same rate through the 4th year of life, but thereafter the females grew faster. Males required more than 13 years and females 11 years to reach 17 inches. A weight of 2 pounds was attained in the 12th year of life by males and in the 10th year by females. Annulus formation extended from mid-June to early August for age-groups I-IV (2nd through 5th year of life). Younger fish started growth earlier in the season than the older fish, and the larger, faster growing members of an age group began growth earlier than the smaller fish. The growing season in 1958 ended in early October. Bottom-water temperatures were about 65A?F when growth started (mid-June) and 58A°F when growth ended. Growth was most rapid in August when temperatures were highest for the year (72A?F). Growth of young of the year, but not of older fish, was positively correlated with temperature during the 1951-57 growing seasons. The sex ratio of the 1958 samples shifted with age; age-groups I-IV contained 54% males, but older age groups had 75% males. Males matured between 7.0 and 15.9 inches (age-groups II-V) and females between 9.0 and 13.4 inches (age-groups III-VII). Spawning in 1958 reached a peak in early July, but extended from mid-June to early August.

Ohio Journal of Science↗
USGS1960

Age and growth of the whitefish Coregonus clupeaformis, of Munising Bay, Lake Superior

This study is based on a sample of 415 whitefish collected in 1953 from an unexploited population in Munising Bay, Lake Superior. Gill-net and trawl catches had different length-frequency distributions and age compositions, but estimates of growth from the two catches were very similar. The body-scale relation is a straight line with an intercept of 1.5 inches. Weight of Munising Bay whitefish captured in June increased as the 3.17 power of the length. Growth in length and weight of Munising Bay whitefish was the slowest yet reported from Great Lakes waters. Munising Bay whitefish required nearly 8 years to reach a length of 10 inches and a full 13 years to reach 15 inches. Slightly more than 8 years were required to reach a weight of 8 ounces and a little less than 14 years to reach 1 pound. The sex ratio of the Munising Bay whitefish exhibited no systematic change with an increase in age. The entire sample for which ages were determined contained 52 percent males. Munising Bay whitefish matured at much shorter lengths but at a greater age than reported for other Great Lakes whitefish populations. The smallest mature males were in the 11.5- to 11.9-inch length interval (age-group VII) and all males longer than 14.4 inches (age-group XII) were mature. The first mature females appeared at 12.0-12.4 inches (age-group X) and all females longer than 14.9 inches (age-group XII) were mature. The more rapidly growing individuals matured earlier than the slow-growing ones.

Transactions of the American Fisheries Society↗