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Abstract has not been submitted...

Diets of salmonines in Lake Michigan have been dominated by alewives Alosa pseudoharengus since the 1960s, and information on alewife population dynamics is critical to the management of salmonine fisheries. We monitored alewife size at age and condition (K) at several different locations in Lake Michigan during fall 1984–2001. Alewives were aged...

We characterized, at millimeter resolution, bacterial biomass, diversity, and vertical stratification of biological soil crusts in arid lands from the Colorado Plateau. Microscopic counts, extractable DNA, and plate counts of viable aerobic copiotrophs (VAC) revealed that the top centimeter of crusted soils contained atypically large bacterial populations, tenfold larger than...

Estimates of larval sea lamprey (Petromyzon marinus) abundance are used to rank Great Lakes tributaries for lampricide treatment. Observers subjectively stratify habitat into three categories: type I = preferred, type II = acceptable, type III = unacceptable. Agreement was evaluated among eight observers classifying habitats in small discrete plots in...

Bayluscide is an additive to TFM that increases the effectiveness of TFM as a lampricide. A review of the literature was undertaken to determine the environmental fate and effects of Bayluscide. Niclosamide (2', 5-dichloro-4'-nitrosalicylanilide), the active ingredient of Bayluscide, degrades rapidly in natural water and sediment systems, however, the rate...

The toxicity of the lampricides 3-trifluoromethyl-4-nitrophenol (TFM) and 2',5-dichloro-4'-nitrosalicylanilide (niclosamide) to non-target fishes has been a major point of concern since their use to control larval sea lamprey (Petromyzon marinus) populations began in the early 1960s. The toxicity of TFM to several non-target fish species has been demonstrated in previous...

The effects of a 12-h exposure to the lampricide 3-trifluoromethyl-4-nitrophenol (TFM) and a combination of TFM and 1% niclosamide (active ingredient in Bayluscide 70% wettable powder) on the short and long-term (10 mo post exposure) survival and behavior of two unionid freshwater mussel species Elliptio complanata and Pyganadon cataracta were...

We analyzed fish abundance and environmental data collected over nine years from six side channels of the unimpounded upper Mississippi River between river km 46.7 and 128.7. A partial canonical correspondence analysis revealed differences in fish assemblages and environmental factors correlated with the six side channels. Fishes correlated with open...

IntroductionThe U.S. Geological Survey (USGS) conducts scientific investigations in south Florida to improve society’s understanding of the environment and assist in the sustainable use, protection, and restoration of the Everglades and other ecosystems within the region. The investigations summarized in this document have been carried out under the Greater Everglades...

Hydrogenetic ferromanganese oxyhydroxide crusts (Fe-Mn crusts) precipitate out of cold ambient ocean water onto hard-rock surfaces (seamounts, plateaus, ridges) at water depths of about 400 to 4000 m throughout the ocean basins. The slow-growing (mm/Ma) Fe-Mn crusts concentrate most elements above their mean...

The efficacy of hydrogen peroxide in controlling saprolegniasis on eggs of walleye Stizostedion vitreum, white sucker Catostomus commersoni, and paddlefish Polyodon spathula was evaluated at four private, state, and federal production hatcheries participating in an Investigational New Animal Drug efficacy study (experiment 1; walleyes) and in a laboratory-based miniature egg...

No abstract available....

Freshwater mussels are emersed (exposed to air) during conservation activities such as surveys and relocations. Success of these activities depends upon the ability of mussels to survive emersion and to re-burrow in the substratum. We evaluated the acute sublethal effects of emersion on three species of unionid mussels [pocketbook, Lampsilis...

Invasions of boll weevil (Anthonomus grandis) into the United States and sea lamprey (Petromyzon marinus) into the Great Lakes were similar in many ways. Important species (American cotton, Gossypium hirsutum, and lake trout, Salvelinus namaycush) and the industries they supported were negatively affected. Initial control efforts were unsuccessful until pesticides...

No abstract available....

Abstract has not been submitted...

Profiles of 4He in pore water were measured in clay aquitards in SW Ontario. The 4He distributions are consistent with groundwater velocities that are <6 mm yr−1, and thus diffusion is the dominant transport mechanism for 4He. Modeling indicates that the effective diffusion coefficient for 4He is 6.3 ± 1.6 × 10−6 cm2 s−1. Furthermore, the...

Grassland bird populations are declining. Invasive plant species may be contributing to these declines by altering habitat quality. However, the effects of invasive plants on grassland birds are largely unknown. Leafy spurge (Euphorbia esula) is an exotic, invasive weed in the northern Great Plains. We examined the effects of leafy spurge infestation on densities of breeding birds, nest-site selection, and nest success in grasslands on the Sheyenne...

We used Sr/Ca and stable isotope data from well dated and preserved corals from the northeastern Caribbean to determine the seasonal environmental conditions for four continuous years during the Eemian, the last time the Earth was in a prolonged warm phase. We determined that the seasonal range in SST during...

The southern rim of the Isidis basin contains one of the highest densities of valley networks, several restricted paleolake basins, and the stratigraphically lowest (oldest) terrain on Mars. Geologic mapping in Viking, MGS/MOC, and MOLA data, Odyssey/THEMIS data, and other multispectral data products supports the presence of extensive fans of...

The U.S. Geological Survey Earth Resources Observation Systems Data Center responds to emergencies in support of various government agencies for human-induced and natural disasters. This response consists of satellite tasking and acquisitions, satellite image registrations, disaster-extent maps analysis and creation, base image provision and support, Web-based mapping services for product...

This study documents the presence of Plasmodium spp. in landbirds of central Polynesia. Blood samples collected from eight native and introduced species from the island of Tutuila, American Samoa were evaluated for the presence of Plasmodium spp. by nested rDNA PCR, serology and/or microscopy. A total of 111/188 birds (59%)...

A national survey of Conservation Reserve Program (CRP) contractees was completed to obtain information about Abstract environmental and social effects of the program on participants, farms, and communities. Of interest were observations concerning wildlife, attitudes about long-term management of program lands, and effectiveness of U.S. Department of Agriculture (USDA) assistance...

A marker based on randomly amplified polymorphic DNA (RAPD), OT-38, was discovered that nonlethally discriminates between stream-type and ocean-type populations of chinook salmon Oncorhynchus tshawytscha in the Columbia River basin, including the threatened fall-run (ocean-type) and spring-run (stream-type) Snake River populations. This marker was developed by amplifying chinook salmon genomic...

Fragmentation of the landscape by large-scale mining may affect Red-shouldered Hawk (Buteo lineatus) populations by reducing the amount of forested habitat available in a landscape and by creating fragmented forest parches surrounded by reclaimed mine lands. We examined habitat characteristics and relative abundance of Red-shouldered Hawks in reclaimed mine landscapes...