Macroinvertebrate communities were compared in dredged and undredged areas of the St. Lawrence River near Cape Vincent, N. Y., by sampling with a Ponar dredge in spring, summer and fall seasons. Total macroinvertebrate abundance was greater in undredged areas. Differences in total invertebrate abundance and relative abundance of individual species in dredged and undredged areas appear to be related to the presence of gyttja-type sediments caused by breakwater construction and dredging operations at least 40 years ago.

From 1980-2006, we showed multiple cohorts of undergraduate faculty how environmental impact analysis can be used in their STEM courses to tie together scientific concepts and theories, research and analytical techniques, and mathematical and communication skills appropriate to address local environmental problems. During more than 20 summer workshops (5 days to 3 weeks), we chose themes of Stressed Stream Analysis or Great Lakes Ecosystem Dynamics because those topics allowed us to demonstrate (and for participants to learn hands-on) new, ecologically based approaches to pollution control and to use spreadsheet models to explore the movements of pollutants in ecological systems. Faculty participants (mostly from the disciplines of biology, chemistry, geology, and engineering) worked in teams to address the environmental problems presented to them by the workshop instructors then wrote environmental impact statements. In later stages of our workshop activities for undergraduate faculty, we also developed units on developing their capacity to use and modify new assessment instruments to gather better data on student learning and managing the challenges of undertaking significant pedagogical and curricular changes in their courses.

In the mid-Columbia River, radio-tagged White Sturgeon (Acipenser transmontanus) exhibited seasonal and diel movement patterns from 1975-1977. Seasonally, movements >2 km away from release locations began in spring when water temperature exceeded 13 oC and ended in autumn when water temperature fell below 13 oC. Daily, sturgeon exhibited movements among habitats with different substrates, as measured by changes in water temperature during 24-h diel periods. Movement to cooler, deeper areas of the river occurred before sunrise, while movement to warmer, shallower areas peaked after sunset. Because water temperatures varied by only a few tenths of a degree among substrate areas, it is likely that photoperiod influenced sturgeon movements between deeper, darker resting areas and shallower, food-rich feeding areas.

To assess potential thermal impacts of Somerset Generating Station on sport fishes, the frequencies and durations of encountering the thermal discharge at Somerset Station were determined by tagging 121 salmonines and 58 centrarchids with temperature-sensing radiotransmitters. Encounters of the Lake Ontario shoreline occupied by Somerset Station averaged 0.7 and 0.1 per fish for salmonines and centrarchids, respectively. Salmonines averaged 5.5 h at the station per encounter. Four centrarchids established residence areas in the lake near the station for 29-79 d; others averaged 3.5 d at the station. Salmonines and centrarchids occupied waters off Somerset Station on 6.7% and 16.0% respectively, of the days they were tracked. No temperatures occupied by fish at the station exceeded critical thermal maxima for salmonines (20 - 25 degrees C) or centrarchids (30 - 37 degrees C). Salmonines occupied heated water >2 degrees C above ambient lake temperatures on 1.3% of the 1,983 occasions when temperatures were recorded, while centrarchids averaged 0.1% of 1,773 observations. Rare encounters of and lack of attraction to the thermal discharge were attributed to characteristics of the discharge (600+ m offshore, small delta T, small volume/area), to unremarkable lake habitat (flat bottom, physically similar to other regions of southcentral Lake Ontario), and to the generally wide-ranging movements of fishes in Lake Ontario. Comparing results from Somerset Station with similar studies at other Great Lakes power stations suggests that discharge design and lake habitat importantly influence the extent of fish attraction to thermal discharges.

Using radiotelemetry and vertical gill nets, we studied the movements and habitat preferences of brown trout (Salmo trutta), steelhead (Oncorhynchus mykiss), Chinook Salmon (O. tshawytscha), Coho Salmon (O. kisutch) and Lake Trout (Salvelinus namaycush) in Lake Ontario. No species were available for radio tagging in the summer, Brown Trout and Chinook and Coho Salmon were available in the fall, and Brown Trout and Steelhead were available in the spring. Steelhead responded strongly to offshore thermal breaks at the surface in the spring. Vertical gill nets in the summer captured Brown Trout just above the thermocline and Lake Trout below it, while Chinook Salmon ranged widely a above and below the thermocline. Our studies helped Lake Ontario anglers to increase their catches of stocked salmonids in the lake.

Since the zebra mussel (Dreissna polymorpha) colonized the Great Lakes Ecosystem, ecologists and managers have expressed concern about potential impacts it would have on native benthic macroinvertebrate communities in lakes and streams. We compared post-Dreissena invasion data (1991-1992) with pre-invasion data (1983) from the same sites in Lake Ontario. Dreissena was the overwhelmingly dominant taxon in 1991-1992. Nevertheless, the overall abundance of other benthic macroinvertebrates, and the number of taxa collected, were greater following establishment of Dreissena. Our study failed to provide evidence that Dreissena had induced a population in any non-bivalve taxon that was present in 1983. The invasion of Dreissena and other recent environmental changes appear to have created conditions that are more favorable for most benthic macroinvertebrate taxa in the nearshore region of Lake Ontario. We also asked why zebra mussels have not colonized many creeks in Western New York, some with apparently ideal habitat, that are fed partially by water from the Erie Canal which is a source of Dreissena larvae. Counts of Dreissena larvae and counts of chlorophyll a were much higher in the canal than in out study creek, yet water quality, current velocity and particulate organic carbon concentrations in the creak and the canal were very similar. Four factors appear to limit colonization of creeks by the zebra mussel: 1) Retention of larvae by wetlands through which discharges from the canal often flow, 2) Filtering of phytoplankton and larvae by dense beds of adult zebra mussels often found at the beginning of channels connecting the canal to creeks, 3) Inappropriate food quality (e.g., lack of small0diameter phytoplankton with important fatty-acid constituents) reaching creeks from the canal, or 4) Muddy substrates inappropriate for attachment and filter-feeding by Dreissena.

A major environmental and economic concern in the Pacific Northwest is the continuing decline in the numbers of Columbia and Snake River salmonids. The author used radiotelemetry to evaluate effect of Little Goose Dam on the movements of chinook salmon in the lower Snake River, and compared the results with those of previous studies at other dams.

Reef fishes in the Gulf of Mexico, particularly snappers (Lutjanidae) and groupers (Serranidae), occupy restricted live bottom habitats that are subjected to intense commercial and recreational fishing. Reliable, fishery-dependent stock assessment methods are needed to make sound population estimates, protect important fishery resources and habitats, and to maintain viable, co-existing commercial and recreational fisheries.

movements and behavior of 56 stream-spawning smallmouth bass and rock bass from Lake Ontario were examined in spring and summer 1985 and 1986. Fish were captured by electrofishing near spawning areas in two tributaries 60 km apart, fitted with temperature-sensing radiotransmitters and released in their "home" tributaries or or displaced to the lake 3 - 10 km from those tributaries. twenty-six percent of displaces smallmouth bass and 42% of rock bass returned to their original sites of capture in tributaries. Non-homing fish generally dispersed along the lake shore and eventually established small residence areas in the lake, often near home or other tributaries. No differences were observed in movement rates, temperatures occupied or diel activity patterns between years or tributary stocks, but differences were found between species and between lake and tributary habitats for smallmouth bass. Smallmouth bass homing to, or released in, tributaries generally established home ranges downstream from spawning areas and often occupied tributaries all summer, but rock bass did not. Both species occupied temperatures between 20-22 C in lake and tributary habitats when available. Smallmouth bass were most active in May, least active in July and generally more active in the lake than in tributaries. Rock bass activity did not appear to vary by season or habitat. Both specie were most active in Lake Ontario in mid-day; differences in tributaries were less pronounced.

Forested riparian buffers are implemented by watershed managers to reduce pollutant runoff into waterbodies. They have been shown to accomplish this task in rivers and streams, but few studies have investigated their efficacy around lakes. Hemlock and Canadice are oligo-mesotrophic lakes with reforested watersheds, including a shoreline buffer strip. Immediately to the west and east of Hemlock and Canadice, Conesus and Honeoye lakes are unprotected, meso-eutrophic systems with mostly mixed, forested, agricultural, and developed land uses. This study explored whether having a shoreline forest buffer strip supports a macroinvertebrate community indicative of good water quality in lakes. In addition, this study examined relationships between individual subwatershed land use and biotic indicators of water quality, as determined by benthic macroinvertebrates. Macroinvertebrate community composition showed some dissimilarity between lakes (R = 0.09, p = 0.04), with the largest dissimilarity between Conesus and Honeoye. Comparisons did not follow expected patterns based on land use, management protections, and presence of a shoreline forest buffer strip. No difference was found in a biotic index of water quality between the lakes. The benthic community of each lake was rated as moderately impacted by humans. Subwatershed land use generally did not correlate with biotic indices of water quality within lakes. This finding suggests that near-shore forest buffers had no measurable effect on benthic macroinvertebrate communities and their biotic indicators of water quality. Macroinvertebrate communities in these lakes are likely driven by within-lake habitat conditions and legacy effects of agricultural land.