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Research about Lake Huron

Source-linked reports with geographic coverage including Lake Huron.

67 records · Page 4Linked to original sources
USGS2011

Long-term trends in habitat use of offshore demersal fishes in western Lake Huron suggest large-scale ecosystem change

We estimated mean depths of capture for offshore demersal fish species, grouped into three habitat-based guilds (shallow benthic, pelagic, and deep benthic), using fall bottom trawl data (27–73 m) in the western main basin of Lake Huron from 1976 to 2007. The mean depth of capture of the shallow and deep benthic guilds initially exhibited a trend toward capture in shallower water, switched to a trend toward capture in deeper water in 1991, and changed back to a trend toward capture in shallower water in 2001–2002. Species in the pelagic guild showed a similar pattern, but the initial change point occurred in 1981 for this guild. Individual species in these guilds showed variable patterns of depth distribution, but a feature common to all guilds and all pelagic and deep benthic species was a change to a trend toward capturing fish in shallower water that occurred nearly simultaneously (1999–2002). These common trends suggest that large-scale factors are affecting the habitat use of offshore demersal fish species in Lake Huron. The depth distributions of the three guilds have converged in recent years, indicating that the locations of suitable habitat for offshore demersal fishes may be changing. Our results indicate that the benthic ecology of the western main basin of Lake Huron is undergoing profound changes across a large spatial scale that are affecting the habitat use of offshore demersal fishes. We suggest that these changes are related to recent invasions of exotic species.

Lake Huron↗
USGS2011

Maximum length and age of round gobies ( Apollonia melanostomus ) in Lake Huron

The round goby ( Apollonia [Neogobius] melanostomus ,) an invasive species, is generally smaller and shorter-lived in the Great Lakes than it native range. We examined 30 large male round gobies from trawl samples taken in Lake Huron and used otoliths to determine their age and back-calculated growth. Standard lengths ranged from 76 to 97 mm, and the oldest fish were age-5. Low water temperatures in nearshore regions of Lake Huron might cause slow growth and late maturation.

Michigan↗
USGS2011

Benthic macroinvertebrate and fish communities in Lake Huron are linked to submerged groundwater vents

Groundwater can be an important source of nutrients and energy to aquatic ecosystems, but quantifying the inputs and biogeochemical importance remains challenging. A series of submerged groundwater vents in northern Lake Huron were examined to determine the linkage between groundwater nutrients and aquatic food webs. We collected samples of key food-web components from groundwater vent and reference habitats and analyzed them for 13 C, 15 N, and 34 S isotopes. Dissolved inorganic carbon (DIC) in the groundwater was depleted in 13 C, while aqueous sulfate was enriched in 34 S (mean differences between groundwater and reference sites were –3.9‰ and +12.0‰, respectively). Benthic primary producers, macroinvertebrates, and benthivorous fish had significantly lower δ 13 C values in groundwater environments, and benthivorous fish were somewhat depleted (–2.5‰) in δ 34 S at groundwater sites compared to reference sites. However, δ 15 N values were not different between groundwater and reference sites, and pelagic components of the ecosystems (plankton and planktivorous and piscivorous fish) were similar in both δ 13 C and δ 15 N. These data suggest benthic metazoan communities surrounding groundwater vents are partially linked to groundwater-derived benthic primary production, while planktivorous and piscivorous communities not directly associated with the benthos do not rely on groundwater nutrients.

Aquatic Biology↗
USGS2010

Increase in lake trout reproduction in Lake Huron following the collapse of alewife: Relief from thiamine deficiency or larval predation?

In the Great Lakes there is still uncertainty as to the population level effects of a thiamine deficiency on salmonines caused by high consumption of alewives Alosa pseudoharengus . A resurgence of lake trout Salvelinus namaycush reproduction in Lake Huron following the crash of alewife stocks between 2002 and 2004 provided an opportunity to evaluate the relative effects of this crash on reproduction through relief from either alewife mediated thiamine deficiency or alewife predation on larval lake trout relative to possible changes in the size of the lake trout spawning stock. Changes in mean lake trout egg thiamine concentration post crash at one spawning reef in Parry Sound, where mean thiamine concentration increased by almost two-fold, were consistent with diet switching from alewives to rainbow smelt Osmerus mordax , the next most abundant prey fish in Lake Huron. Although thiamine levels for lake trout collected at a second reef in Parry Sound did not change post-crash, levels both pre- and post-crash were consistent with a rainbow smelt diet. A reef specific fry emergence index was found to be positively related to reef specific egg thiamine concentration but negatively related to reef specific occurrence of EMS, a thiamine deficiency related mortality syndrome. We found little evidence for overlap between the timing of spring shoreward migration of alewives and lake trout emergence, suggesting that relief from alewife predation effects had relatively little effect on the observed increase in lake trout recruitment. Numbers of spawners in the north, north-central, and southern zones of the lake increased from 2000 onwards. Overall the abundance post-2003 was higher than from pre-2004, suggesting that spawner abundance may also have contributed to increased lake trout reproduction. However, predicted numbers of spawners and measured abundance of wild recruits in assessment gear were poorly correlated suggesting that the increase in reproduction was not totally spawner dependent and hence relief from thiamine deficiency was also likely involved. We conclude from this that eliminating the effects of an alewife diet mediated thiamine deficiency can have positive effects on lake trout reproduction but more research is required to understand the effect of spawner number and the role of spawning habitat availability.

Lake Huron↗
USGS2009

Diets of aquatic birds reflect changes in the Lake Huron ecosystem

Human activities have affected the Lake Huron ecosystem, in part, through alterations in the structure and function of its food webs. Insights into the nature of food web change and its ecological ramifications can be obtained through the monitoring of high trophic level predators such as aquatic birds. Often, food web change involves alterations in the relative abundance of constituent species and/or the introduction of new species (exotic invaders). Diet composition of aquatic birds is influenced, in part, by relative prey availability and therefore is a sensitive measure of food web structure. Using bird diet data to make inferences regarding food web change requires consistent measures of diet composition through time. This can be accomplished by measuring stable chemical and/or biochemical “ecological tracers” in archived avian samples. Such tracers provide insights into pathways of energy and nutrient transfer. In this study, we examine the utility of two groups of naturally-occurring intrinsic tracers (stable isotopes and fatty acids) to provide such information in a predatory seabird, the herring gull ( Larus argentatus ). Retrospective stable nitrogen and carbon isotope analysis of archived herring gull eggs identified declines in gull trophic position and shifts in food sources in Lake Huron over the last 25 years and changes in gull diet composition were inferred from egg fatty acid patterns. These independent groups of ecological tracers provided corroborating evidence of dietary change in this high trophic level predator. Gull dietary shifts were related to declines in prey fish abundance which suggests large-scale alterations to the Lake Huron ecosystem. Dietary shifts in herring gulls may be contributing to reductions in resources available for egg formation. Further research is required to evaluate how changes in resource availability may affect population sustainability in herring gulls and other waterbird species. Long-term biological monitoring programs are required to identify ecosystem change and evaluate its ecological significance.

Lake Huron↗
USGS2009

The Lake Huron pelagic fish community: persistent spatial pattern along biomass and species composition gradients

Spatial patterns in the biomass of pelagic fish in Lake Huron have persisted over 10 years even though biomass decreased 86% and the fish community shifted from dominance by non-native species (rainbow smelt, Osmerus mordax) to dominance by native species (bloater, Coregonus hoyi). Based on multivariate analyses of acoustic biomass data and abiotic variables from the years 1997, 2004, 2005, and 2007, the strength of relationships between abiotic variables (primarily bottom depth) and fish community composition gradients decreased with fish biomass, suggesting that at high biomass, the influence of the measured abiotic variables is minimal. We observed consistently higher biomass in the North Channel and Georgian Bay than in the Main Basin, and as a result, we conclude that these smaller basins are likely important contributors to lakewide fish biomass, production, and dynamics. These results suggest that at current biomass levels, efforts to understand ecology, population dynamics, and lakewide abundance need to incorporate the effects of depth and geographic variation on fish distributions and ecology.

Canadian Journal of Fisheries and Aquatic Sciences↗
USGS2009

Status and trends of the Lake Huron deepwater demersal fish ommunity, 2008

The U.S.Geological Survey Great Lakes Science Center has conducted trawl surveys to assess annual changes in the deepwater demersal fish community of Lake Huron since 1973. Since 1992, surveys have been carried out using a 21 m wing trawl towed on-contour at depths ranging from 9 to 110 m on fixed transects. Sample sites include five ports in U.S. waters with less frequent sampling near Goderich, Ontario. The 2008 fall bottom trawl survey was carried out between October 24 and November 20, 2008 and sampled only the three northern U.S. ports at DeTour, Hammond Bay, and Alpena due to mechanical problems with the research vessel and prolonged periods of bad weather. Therefore, all data presented for 2008 are based on samples collected from these ports. Compared to previous years, alewife populations in Lake Huron remain at low levels after collapsing in 2004. Age-0 alewife density and biomass appears to have increased slightly but overall levels remain near the nadir observed in 2004. Density and biomass of adult and juvenile rainbow smelt showed a decrease from 2007 despite record-high abundance of juveniles observed in 2005, suggesting recruitment was low. Numbers of adult and juvenile bloater were low despite recent high year-classes. Abundances for most other prey species were similar to the low levels observed in 2005 - 2007. We captured one wild juvenile lake trout in 2008 representing the fifth consecutive year that wild lake trout were captured in the survey. Based on pairwise graphical comparisons and nonparametric correlation analyses, dynamics of prey abundance at the three northern ports followed lakewide trends since 1992. Density of benthic macroinvertebrates was at an all-time low in 2008 since sampling began in 2001. The decline in abundance was due to decreases in all taxonomic groups and a large reduction in recruitment of quagga mussels. Density of Diporeia at northern ports in 2008 was the lowest observed. Diporeia were found only at 73-m sites of three ports sampled in northern Lake Huron. While no lakewide estimate of prey biomass was calculated due to the limited spatial scope of the 2008 survey, existing data suggest prey biomass remains depressed. Prey available to salmonids during 2009 will likely be small alewives, small rainbow smelt and small bloaters. Predators in Lake Huron will continue to face potential prey shortages.

Lake Huron↗
USGS2005

Occurrence of Cyathocephalus truncatus (Cestoda) in fishes of the Great Lakes with emphasis on its occurrence in round gobies (Neogobius melanostomus) from Lake Huron

Cyathocephalus truncatus is a pathogenic cestode that is common in many Laurentian Great Lakes fish species, but the depth distribution of this cestode has not been studied. Cyathocephalus truncatus has been reported from 21 fish species and one hybrid representing seven orders and nine families in Lakes Superior, Michigan, Huron, and Ontario. We examined the intestinal contents of six species of fish collected in Michigan waters of Lake Huron, from DeTour to Harbor Beach, in 2001 to 2003 for the presence of this cestode species. Cyathocephalus truncatus was found in five native fish species and the exotic round goby. Prevalence (52%) and mean intensity (4.6 cestodes per infected fish) were highest in bloaters. This is the first reported occurrence of this cestode in round gobies from the Great Lakes. None of the gobies trawled from Lake Huron at depths of 27 to 46 m were infected, but prevalence and intensity of infection in round gobies increased significantly with depth from 55 to 73 m. Our diet study of round gobies indicated that they preyed heavily on amphipods ( Diporeia hoyi ) at depths of 55 to 73 m. Cyathocephalus truncatus was found in eight of 605 D. hoyi obtained by Ponar grab sampling. This suggests that C. truncatus eggs may be released from infected gobies and sink to deep basins with silt bottoms where D. hoyi occur.

Lake Huron↗
USGS2000

Helminths in an intensively stocked population of lake trout, Salvelinus namaycush, from Lake Huron

Eighty stocked lake trout Salvelinus namaycush (Salmonidae), collected from 2 locations in Lake Huron in May 1995, were examined for parasites. The parasite fauna of this top predator in Lake Huron was characterized by only 6 helminth species. Echinorhynchus salmonis infected all lake trout with a mean intensity of 163.9. The intensity of this acanthocephalan species significantly increased with host length and weight. Eubothrium salvelini infected 78 lake trout with a maximum number of 81 scoleces counted. Diplostomum sp., Cyathocephalus truncatus, Capillaria salvelini, and Neoechinorhynchus sp. infrequently infected lake trout. The low parasite species richness in these lake trout is believed to be due to their large size at stocking and to the loss of historical enzootic host–parasite relationships that followed the absence of this fish species in Lake Huron for 26 yr.

Michigan, Ontario↗
USGS1989

Hybridization of ciscoes ( Coregonus spp.) in Lake Huron

Gill raker number and length were compared for lake herring, Coregonus artedii LeSueur, and bloater, Coregonus hoyi (Gill), collected in 1917, 1956, and 1984-1985 at four locations in western Lake Huron to examine the effects of suspected introgressive hybridization on these distinctive species characters. Gill raker length showed no change from 1917 to 1984-1985, but gill raker number became similar in the two species over that period. Between 1917 and 1984-1985, mean gill raker counts decreased from 48.0 to 45.8 in lake herring, but increased from 41.8 to 43.1 in bloaters. The modal count for both species was 43 in 1984-1985. Intermediate gill raker counts were consistent with the hypothesis of hybridization. Bloater abundance increased greatly in the 1980's, but lake herring remained scarce. Under these circumstances, the rare lake herring would be increasingly likely to encounter abundant ripe bloaters during the overlapping spawning seasons of these species, increasing the probability for hybridization. Basic biological differences between the species, such as lower vulnerability of bloaters to commercial harvest, better survival of bloater fry, or greater fecundity of bloaters, may have contributed to the substantially better success of bloaters. Cisco populations are fragile; only the bloater has ever made a strong and sustained recovery after a severe decline. Hybridization with bloaters may impede the recovery of lake herring in Lake Huron.

Canadian Journal of Zoology↗
USGS1983

Additions of nutrients and major ions by the atmosphere and tributaries to nearshore waters of northwestern Lake Huron

Nutrient additions by the atmosphere and six tributaries to nearshore waters of northwestern Lake Huron were measured at weekly intervals from August 1975 to July 1976. The atmosphere contributed 43% of the nitrogen (N) and 10% of the phosphorus (P) that was added during the year. The 1975–76 atmospheric loading rate of total N to this area (11 kg/ha/yr) was one of the highest found to date in the United States. N was conserved more efficiently than P in the tributary drainage basins. Of the N and P that fell annually on the watersheds under study, 2 to 37% of the N and 31 to 84% of the P was carried with runoff to the lake. From a basin where ditching and clear-cutting occurred, water, P, silica (SiO 2 ), N, and sodium were lost at higher rates than from five other basins. Most of the N in bulk atmospheric samples (23%) and tributary waters (56%) was dissolved organic N, a form of N not often measured.

Michigan↗
USGS1982

Alewives and rainbow smelt in Lake Huron: midwater and bottom aggregations and estimates of standing stocks

The continued availability of adequate amounts of forage fish, primarily alewives Alosa pseudoharengus and rainbow smelt Osmerus mordax , is critical to the success of ongoing programs aimed at rebuilding lake trout Salvelinus namaycush populations and maintaining other salmonid stocks in Lake Huron. These forage species are distributed at middepths as well as on or near the bottom. Acoustic methods were integrated with midwater and bottom trawling to characterize the population and estimate the biomass of the forage stocks. The average sizes of alewives and rainbow smelt caught at middepths were smaller than those caught in bottom trawls; however, most size ranges in the bottom trawl catches were also present in the midwater catches. Subadult and adult fish (both species) were rarely caught concurrently in midwater and when they were caught together the fish were invariably large subadults and small adults. Biomass estimates for the pelagic component were determined from trawl catches and echogram counts. The regression of echogram counts ( X ) on trawl catches ( Y ) was Y = -2.69 + 0.983 X (r 2 = 0.766) at the fish densities investigated. The pelagic biomasses of alewives and rainbow smelt in United States waters of Lake Huron were estimated at 17,200 t in July 1974, 22,000 t in July 1975, and 19,000 t in August 1976. Biomass estimates of the stocks in midwater were usually larger in spring than in fall, probably due to seasonal differences in distribution rather than in abundance. Estimates for the demersal component of the combined alewife-rainbow smelt forage stock, calculated from stratified random sampling of the spring bottom trawl catches for 1973 through 1980 went from 35,000 t in 1973, to a high of 83,000 t in 1975, and to 72,000 t in 1980; the estimates in fall went from 31,000 t in 1973, to a high of 56,000 t in 1977, and to 43,000 t in 1980. Biomass estimates calculated from spring catch data were usually larger than those calculated from fall data. Estimates of the midwater stocks, coinciding with the spring and fall bottom trawl surveys, indicated that between 20 and 30% of the total biomass was in midwater.

Lake Huron↗