Geology topics

Bruce A. Manny

Publications and source records attributed to Bruce A. Manny.

At least 37 records · Page 2Linked to original sources

USGS1999

Changes in the bottom fauna of western Lake Erie

The bottom fauna of western Lake Erie has changed dramatically over the past 50 years in response to environmental degradation and biological invasions. In 1953, low dissolved oxygen reduced the biodiversity of that fauna, especially burrowing mayflies and freshwater mussels (Unionidae). Canada and the United States signed the Great Lakes Water Quality Agreement in 1972. By 1982, over 7 billion dollars were spent to improve wastewater treatment plants in the Great Lakes Basin. To assess how the bottom fauna responded to pollution abatement measures, we studied the distribution, abundance, and diversity of bottom fauna in western Lake Erie in 1982 and compared our findings to those of Carr and Hiltunen (1965). Zebra mussels (Dreissena polymorpha) invaded Lake Erie in 1986 and greatly altered these waters. For perspective, we also compared our results to bottom fauna present at the same stations in 1930 (by reference to data in Carr and Hiltunen, 1965) and reviewed the responses of burrowing mayflies and freshwater mussels to the zebra mussel invasion.

Book chapter↗

USGS1996

Recovery of burrowing mayflies (Ephemeroptera: Ephemeridae: Hexagenia ) in western Lake Erie

Burrowing mayflies ( Hexagenia spp.) are native to western Lake Erie and were abundant until the 1950s, when they disappeared due to degraded water and sediment quality. Nymphs were absent from the sediments of most of western Lake Erie after the 1950s, although small, widely disjunct populations apparently persisted near shore. Sediment samples collected in 1993 revealed several small populations near the western and southern shores and beyond the mouths of the Detroit and Maumee rivers. A larger population was found in the southern island area, but nymphs were absent in the middle of the basin. By 1995, nymphs had spread throughout the western half and eastern end of the basin but remained absent from the middle of the basin. These data indicate that Hexagenia began recolonizing nearshore areas before offshore areas. Increasingly large swarms of winged Hexagenia on shore and over the lake between 1992 and 1994 further indicate that mayflies are recolonizing the basin. Factors that have permitted Hexagenia recovery in western Lake Erie probably include improved sediment and water quality attributed to pollution abatement programs implemented after the early 1970s, and perhaps environmental changes in the early 1990s attributed to effects of the exotic zebra mussel ( Dreissena polymorpha ).

Journal of Great Lakes Research↗

USGS1995

Oligochaete fauna of western Lake Erie 1961 and 1982: Signs of sediment quality recovery

The oligochaete fauna at 40 stations in western Lake Erie were collected in 1982 and compared to oligochaete fauna collected similarly in 1961. A total of 34 taxa, representing 18 Tubificidae and 16 Naididae, were identified. Changes in the proportions of low, moderate, and heavy polluted sediments, as determined by ranges of total numbers of oligochaetes, indicate that, in general, heavy pollution substantially decreased near shore and moderate pollution increased and low pollution decreased in open waters over the 21-year comparison. The most common taxon, the eutrophic species, Limnodrilus hoffmeisteri , decreased in abundance in open water, indicating decreased eutrophication, whereas the distribution and abundance of other indicator taxa, including the eutrophic species L. maumeensis , L. cervix , Quistadrilus multisetosus multisetosus , and mesotrophic species Ilyodrilus templetoni and three species of Aulodrilus indicate increased eutrophication in open water. In general, oligochaete trophic indices (based on tubificid species and abundances) in traditional area designations used in 1961, the nearshore designation (<3.5 km from shore), and areas defined by cluster analysis confirm results of less eutrophic substrates near shore. However, traditional analysis indicates that low pollution was replaced by moderate pollution in open waters and cluster analysis indicates that the zone of least detectable pollution increased in open waters over the 21-year comparison. It may be that the open waters of western Lake Erie were in a stage of transition between pollution designations when sampled in 1982. The present study is valuable because it provides a baseline to assess environmental changes observed in western Lake Erie after many years of pollution abatement programs and before the exponential increase in densities of the trophic shifting zebra mussel Dreissena polymorpha.

Journal of Great Lakes Research↗

USGS1995

Survival of lake trout eggs on reputed spawning grounds in Lakes Huron and Superior: In situ incubation, 1987-1988

Lake trout reproduce widely in Lake Superior but little in Lake Huron. We examined whether survival of lake trout eggs and fry in either lake was reduced by physical disturbances and swim-up mortality. Eggs were collected from feral lake trout in Lake Superior and placed in 108 plastic incubators. A total of 48 incubators was set at Partridge Island Reef in southern Lake Superior, 48 were set at Port Austin Reef in southern Lake Huron, and 12 were held as controls inflowing well water at a laboratory. Survival-to-hatching of these eggs at Partridge Island Reef (18%) was significantly different from that at Port Austin Reef (43%) and significantly different in the laboratory (88%) from that at either reef (P < 0.05). During egg-fry incubation from 28 October 1987 to 5 May 1988, 11–18 cm of sediment accumulated in sediment traps placed on the reefs but < 1 cm of sediment was present on each reef in May 1988. Analysis showed that 44% of the eggs at Port Austin Reef and 28% of those at Partridge Island Reef were buried and killed by sediments. During the first week after deployment, mean wave energy was 90% higher at Partridge Island Reef and significantly different from that at Port Austin Reef. Wave energy may be a habitat condition that makes Partridge Island Reef less suitable than Port Austin Reef for incubation of lake trout eggs. Fry from eggs incubated at all three sites experienced no swim-up mortality. We conclude that in 1987–88 habitat conditions required for survival of lake trout eggs were more suitable at Port Austin Reef than at Partridge Island Reef.

Journal of Great Lakes Research↗

USGS1995

An evaluation of lake trout reproductive habitat on Clay Banks Reef, northwestern Lake Michigan

The extinction of the native populations of lake trout ( Salvelinus namaycush ) in Lake Michigan in about 1956 has been followed by a decades-long attempt to reestablish self-sustaining populations of this valuable species in habitats it formerly occupied throughout the lake. One of the most recent management strategies designed to facilitate recovery was to make a primary management objective the establishment of sanctuaries where stocked lake trout could be protected and self-sustaining populations reestablished. In the present study we employed habitat survey and mapping techniques, field and laboratory bioassays, egg traps, sediment traps, and gill nets to examine the potential for successful natural reproduction by stocked lake trout on Clay Banks Reef in the Door-Kewaunee sanctuary in Wisconsin waters of Lake Michigan. Our study revealed (1) there was suitable habitat on the reef to support the production of viable fry, (2) spawner abundance on the reef was the highest recorded in the great lakes, and (3) eggs taken from spawners on the reef and held on the reef in plexiglas incubators hatched and produced fry that survived through swim-up. We conclude that Clay Banks Reef has the potential to support successful natural reproduction by stocked lake trout.

Journal of Great Lakes Research↗

USGS1995

Lake trout spawning habitat in the Great Lakes - a review of current knowledge

We review existing information on lake trout spawning habitat, which might indicate whether habitat is now a limiting factor in lake trout reproductive success. Lake trout spawning habitat quality is defined by the presence or absence of olfactory cues for homing, reef location with respect to the shoreline, water depth, proximity to nursery areas, reef size, contour, substrate size and shape, depth of interstitial spaces, water temperature at spawning time, water quality in interstitial spaces, and the presence of egg and fry predators. Data on factors which attracted native spawners to spawning reefs are lacking, due to the absence of historic data on egg deposition. No direct evidence of egg deposition has been collected from sites deeper than 18 m. Interstitial space and, therefore, substrate size and shape, appear to be critical for both site selection by adults and protection of eggs and fry. Water quality is clearly important for egg incubation, but the critical parameters which define water quality have not yet been well determined in the field. Exposure to wave energy, dictated in part by reef location, may maintain high water quality but may also damage or dislodge eggs. The importance of olfactory cues, water temperature, and proximity to nursery habitat to spawning trout is unclear. Limited data suggest that egg and fry predators, particularly exotic species, may critically affect fry production and survival. Although availability of physical spawning habitat is probably not limiting lake trout reproduction, changes in water quality and species composition may negatively affect early life stages. This review of habitat factors that affect early life stages of lake trout suggests several priorities for research and management.

Journal of Great Lakes Research↗

USGS1994

Nutrient additions by waterfowl to lakes and reservoirs: predicting their effects on productivity and water quality

Lakes and reservoirs provide water for human needs and habitat for aquatic birds. Managers of such waters may ask whether nutrients added by waterfowl degrade water quality. For lakes and reservoirs where primary productivity is limited by phosphorus (P), we developed a procedure that integrates annual P loads from waterfowl and other external sources, applies a nutrient load-response model, and determines whether waterfowl that used the lake or reservoir degraded water quality. Annual P loading by waterfowl can be derived from a figure in this report, using the days per year that each kind spent on any lake or reservoir. In our example, over 6500 Canada geese ( Branta canadensis ) and 4200 ducks (mostly mallards, Anas platyrhynchos ) added 4462 kg of carbon (C), 280 kg of nitrogen (N), and 88 kg of P y -1 to Wintergreen Lake in southwestern Michigan, mostly during their migration. These amounts were 69% of all C, 27% of all N, and 70% of all P that entered the lake from external sources. Loads from all external sources totaled 840 mg P m -2 y -1 . Application of a nutrient load-response model to this concentration, the hydraulic load (0.25 m y -1 ), and the water residence time (9.7 y) of Wintergreen Lake yielded an average annual concentration of total P in the lake of 818 mg m -3 that classified the lake as hypertrophic. This trophic classification agreed with independent measures of primary productivity, chlorophyll- a , total P, total N, and Secchi disk transparency made in Wintergreen Lake. Our procedure showed that waterfowl caused low water quality in Wintergreen Lake.

Hydrobiologia↗

USGS1991

Heavy metals in aquatic macrophytes drifting in a large river

Macrophytes drifting throughout the water column in the Detroit River were collected monthly from May to October 1985 to estimate the quantities of heavy metals being transported to Lake Erie by the plants. Most macrophytes (80–92% by weight) drifted at the water surface. Live submersed macrophytes made up the bulk of each sample. The most widely distributed submersed macrophyte in the river, American wildcelery (Vallisneria americana) , occurred most frequently in the drift. A total of 151 tonnes (ash-free dry weight) of macrophytes drifted out of the Detroit River from May to October. The drift was greatest (37 tonnes) in May. Concentrations of heavy metals were significantly higher in macrophytes drifting in the river than in those growing elsewhere in unpolluted waters. Annually, a maximum of 2796 kg (eight heavy metals combined) were transported into Lake Erie by drifting macrophytes. The enrichment of all metals was remarkably high (range: 4000 × to 161000 ×) in macrophytes, relative to their concentration in water of the Detroit River. Detroit River macrophytes are thus a source of contaminated food for animals in the river and in Lake Erie.

Hydrobiologia↗

USGS1991

The Detroit River: Effects of contaminants and human activities on aquatic plants and animals and their habitats

Despite the extensive urbanization of its watershed, the Detroit River still supports diverse fish and wildlife populations. Conflicting uses of the river for waste disposal, water withdrawals, shipping, recreation, and fishing require innovative management. Chemicals added by man to the Detroit River have adversely affected the health and habitats of the river's plants and animals. In 1985, as part of an Upper Great Lakes Connecting Channels Study sponsored by Environment Canada and the U.S. Environmental Protection Agency, researchers exposed healthy bacteria, plankton, benthic macroinvertebrates, fish, and birds to Detroit River sediments and sediment porewater. Negative impacts included genetic mutations in bacteria; death of macroinvertebrates; accumulation of contaminants in insects, clams, fish, and ducks; and tumor formation in fish. Field surveys showed areas of the river bottom that were otherwise suitable for habitation by a variety of plants and animals were contaminated with chlorinated hydrocarbons and heavy metals and occupied only by pollution-tolerant worms. Destruction of shoreline wetlands and disposal of sewage and toxic substances in the Detroit River have reduced habitat and conflict with basic biological processes, including the sustained production of fish and wildlife. Current regulations do not adequately control pollution loadings. However, remedial actions are being formulated by the U.S. and Canada to restore degraded benthic habitats and eliminate discharges of toxic contaminants into the Detroit River.

Hydrobiologia↗

USGS1991

Heavy metal contamination of sediments in the upper connecting channels of the Great Lakes

In 1985, sampling at 250 stations throughout the St. Marys, St. Clair, and Detroit rivers and Lake St. Clair — the connecting channels of the upper Great Lakes — revealed widespread metal contamination of the sediments. Concentrations of cadmium, chromium, copper, lead, mercury, nickel, and zinc each exceeded U.S. Environmental Protection Agency sediment pollution guidelines at one or more stations throughout the study area. Sediments were polluted more frequently by copper, nickel, zinc, and lead than by cadmium, chromium, or mercury. Sediments with the highest concentrations of metals were found (in descending order) in the Detroit River, the St. Marys River, the St. Clair River, and Lake St. Clair. Although metal contamination of sediments was most common and sediment concentrations of metals were generally highest near industrial areas, substantial contamination of sediments by metals was present in sediment deposition areas up to 60 km from any known source of pollution.

Hydrobiologia↗

USGS1991

Distribution of Hexagenia nymphs and visible oil in sediments of the Upper Great Lakes connecting channels

As part of the study of the Upper Great Lakes Connecting Channels sponsored by the U.S. Environmental Protection Agency, the U.S. Fish and Wildlife Service examined the occurrence of Hexagenia nymphs and visible oil in sediments at 250 stations throughout the St. Marys River and the St. Clair-Detroit River system from May 14 to June 11, 1985. The mean density of Hexagenia nymphs per square meter averaged 194 for the total study area, 224 in the St. Marys River, 117 in the St. Clair River, 279 in Lake St. Clair, and 94 in the Detroit River. The maximum density of nymphs ranged from 1,081 to 1,164 m -2 in the three rivers and was 3,099 m -2 in Lake St. Clair. A comparison of nymph density at 46 stations where oil was observed in sediments physically suitable for nymphs showed that densities were lower in oiled sediments (61 m -2 ) than in sediments without oil (224 m -2 ). Densities of nymphs were relatively high at only four stations where oil was observed in sediments. In general, oiled sediments and low densities of nymphs occurred together downstream from industrial and municipal discharges.

Hydrobiologia↗

USGS1991

Production of Hexagenia limbata nymphs in contaminated sediments in the Upper Great Lakes connecting channels

In April through October 1986, we sampled sediments and populations of nymphs of the burrowing mayfly, Hexagenia limbata (Serville), at 11 locations throughout the connecting channels of the upper Great Lakes, to determine if sediment contaminants adversely affected nymph production. Production over this period was high (980 to 9231 mg dry wt m -2 ) at the five locations where measured sediment levels of oil, cyanide, and six metals were below the threshold criteria of the U.S. Environmental Protection Agency and the Ontario Ministry of Environment for contaminated or polluted sediments, and also where the criterion for visible oil given in the Water Quality Agreement between the U.S.A. and Canada for connecting waters of the Great Lakes was not exceeded. At the other six locations where sediments were polluted, production was markedly lower (359 to 872 mg dry wt m -2 ). This finding is significant because it indicates that existing sediment quality criteria can be applied to protect H. limbata from oil, cyanide, and metals in the Great Lakes and connecting channels where the species fulfills a major role in secondary production and trophic transfer of energy.

Hydrobiologia↗

USGS1991

Long-term decline in freshwater mussels (Bivalvia: Unionidae) of the western basin of Lake Erie

Long-term trends in the abundance of unionids in the western basin of Lake Erie were examined from data collected at 17 stations in 1961, 1972, and 1982. The mean number of unionids at these stations declined over this time period, decreasing from 10 m −2 in 1961, to 6 m −2 in 1972, down to 4 m −2 in 1982. This decline in abundance was reflected in the decrease in the number of stations where mussels were found; unionids were found at 16 of the 17 stations in 1961, but at only 6 stations in 1982. Reasons for the decrease in the unionid population are not generally apparent, but are probably related to the decline in water quality and periods of low oxygen levels over the time period of the surveys.

Lake Erie↗

USGS1991

Burrowing mayfly nymphs in western Lake Erie, 1942-1944

These data, collected during 1942-1944 by Dr. David C. Chandler, describe the density, biomass, and growth of a now extinct population of burrowing mayfly nymphs (primarily Hexagenia limbata ) that lived in the sediments of western Lake Erie near South Bass Island. The growth dynamics of this population have not previously been documented. Female nymphs grew faster than males and were about 4 mm longer than males at emergence each year. Significantly fewer nymphs were collected in 1943 than in 1942 or 1944. Before they were extinguished by low dissolved oxygen in 1953, mayfly nymphs were abundant (about 350 weighing 10 wet g m -2 ) near this island and throughout most of western Lake Erie. The western basin once supported a biomass of 9.6 t · km -2 or at least 17,600 metric tonnes of mayfly nymphs. If burrowing mayflies recolonize the sediments of western Lake Erie, these data could be used to assess the extent of their recovery.

Lake Erie;South Bass Island↗

USGS1991

Compsopogon cf. coeruleus , a benthic red alga (Rhodophyta) new to the Laurentian Great Lakes

We found Compsopogon cf. coeruleus for the first time in the Laurentian Great Lakes, growing on limestone rocks at a depth of 21&ensp;m on Six Fathom Bank in central Lake Huron. It is the first freshwater red alga to be found in the Great Lakes and the only red alga ever found on an offshore reef in the Great Lakes. However, because this alga usually inhabits water 10–28 °C and has not survived freezing winter temperatures elsewhere, it may not be a permanent member of the flora.

Canadian Journal of Botany↗

USGS1991

Chemical contamination and physical characteristics of sediments in the upper Great Lakes connecting channels 1985

Contamination of sediments by toxic organic substances and heavy metals was widespread throughout the connecting channels of the upper Great Lakes in 1985. Sediments at 250 stations in the connecting channels were analyzed for total PCBs, oil and grease, phenols, total cyanide, total volatile solids, mercury, cadmium, chromium, cobalt, copper, lead, nickel, and zinc, and the results were evaluated according to U.S. EPA guidelines for polluted sediments. Sediments were most heavily contaminated near industrialized areas, although some areas more than 40 km downstream from known point sources of pollution were moderately contaminated by oil and metals.

Report↗

USGS1990

Decline of wildcelery buds in the lower Detroit River, 1950-85

American wildcelery buds (Vallisneria americana), an abundant food eaten by diving ducks (Aythini) during migrations, decreased in the lower Detroit River of the Great Lakes from 1950 to 1985. Bud densities decreased at 2 (-14 and -18 buds/mA?) of 5 locations and were similar at 3 (-2, +2, and +3 buds/mA?) of 5 locations. Net change in all 5 areas combined, however, was a decrease of 36,720,000 buds, a 72% decline. Estimated potential losses of waterfowl feeding days caused by the decreased bud densities were 147,000 for canvasbacks (Aythya valisineria), 241,000 for redhead ducks (A. americana), or 664,000 for lesser scaup (A. affinis). Thus, the decline of wildcelery in the Detroit River may have contributed to decreased use of Michigan migration routes by some waterfowl species between 1950 and 1985.

Journal of Wildlife Management↗

USGS1989

Assessment of lake trout spawning habitat quality in central Lake Huron by submarine

Interstitial water quality was measured using a submersible at seven locations on Six Fathom Bank. Historically, the bank was an important lake trout spawning ground. It is currently the focus of coordinated, interagency efforts to rehabilitate lake trout in Lake Huron. Water quality, evaluated from measurements of biochemical oxygen demand, dissolved oxygen, ammonia, and hydrogen sulfide among the rocks, would not prevent lake trout eggs from hatching successfully on the bank.

Journal of Great Lakes Research↗