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At least 1,405 records · Page 78Linked to original sources
USGS1960

Evaporation control research, 1955-58

One hundred fifty-two compounds and compositions of matter were screened as potential evaporation retardants. The homologous straight-chain fatty alkanols are considered the best materials for retardants. Several methods of application of the alkanols to the reservoir surface were investigated. Although wick-type drippers for the application of liquids and cage rafts for the application of solids appear to be the most promising methods from an economic standpoint, both methods have serious disadvantages. Considerable study was given to reducing biochemical oxidation of the evaporation retardants. Copper in several forms was found adequate as a bacteriostatic agent but posed a potential hazard because of its toxicity. Many other bactericides that were tested were also toxic. Two sets of large-scale field tests have been completed and several others are still in progress. On the larger reservoirs, the reduction of evaporation was not more than 20 percent under the prevailing conditions and the application procedure used. Three major practical problems remain; namely, the effects and action of wind on the monofilm, the effects of biochemical oxidation, and the most effective method of application. Fundamental problems remaining include the effects of various impurities, and the composition of the best evaporation retardant; the long-range effects of monofilms on the limnology of a reservoir, including the transfer of oxygen and carbon dioxide; toxicological aspects of all components of any evaporation-retardant composition, plus toxicology of any composition chosen for large-scale use; and further studies of the calorimetry and thermodynamics involved in the mechanism of evaporation and its reduction by a monofilm.

Water Supply Paper↗
USGS1998

Cadmium resistance in an oligochaete and its effect on cadmium trophic transfer to an omnivorous shrimp

It has been demonstrated that the deposit-feeding oligochaete Limnodrilus hoffmeisteri inhabiting Foundry Cove (FC), a severely cadmium (Cd)-contaminated cove located on the Hudson River, New York, USA, has evolved resistance to Cd. In this study we investigate how this resistance influences Cd trophic transfer from this oligochaete to the grass shrimp Palaemonetes pugio. Cadmium-resistant worms collected from FC and nonresistant worms collected from an adjacent unpolluted site were investigated for differences in Cd tolerance, accumulation, subcellular distribution and bioavailability to shrimp. FC worms were more tolerant of Cd, surviving twice as long as worms from the unpolluted site during a toxicity bioassay. The 7 d concentration factor of Cd-resistant worms was 4 times greater than that of nonresistant worms (2020 vs 577). There were also differences between worm populations with respect to subcellular Cd distributions. Cd-resistant worms produced metallothionein-like proteins (MT) as well as metal-rich granules (MRG) for Cd storage and detoxification; nonresistant worms only produced MT. These differences in subcellular Cd distributions led to large differences in Cd bioavailability to shrimp; shrimp fed Cd-resistant worms absorbed 21% of the ingested Cd, while those fed nonresistant worms absorbed roughly 4 times that amount (~75%). These absorption efficiencies were in good agreement with the proportions of Cd bound to the worm's most biologically available subcellular fractions (i.e. the cytosol and organelles). Although Cd-resistant worms predominantly stored the toxic metal in biologically unavailable MRG, their increased accumulation of Cd would still result in substantial trophic transfer to shrimp because of the storage of Cd in the biologically available fractions. This work demonstrates that the evolution of Cd resistance can have profound implications for Cd bioavailability and cycling within aquatic ecosystems.

Marine Ecology Progress Series↗
USGS2022

What’s It worth? Estimating the potential value of early warnings of cyanobacterial harmful algal blooms for managing freshwater reservoirs in Kansas, United States

Cyanobacterial blooms are an issue drawing increasing concern in freshwater lakes and reservoirs in the United States due to the real and sometimes perceived harms they can cause through cyanotoxin production or other effects. These types of blooms are often referred to as cyanobacterial harmful algal blooms (cyanoHABs). Cyanotoxin exposure can potentially lead to human health effects through recreation and consumption of drinking water and may impact fisheries, wildlife, domestic pets, and livestock. Characterizing the societal impacts of cyanotoxin production, exposure, and effects and estimating the potential value of information of an early warning system can inform and support freshwater lake and reservoir management decisions and future research directions. A Bayesian decision tree analysis was utilized to identify uses, users, and benefits of the information provided by this research. Specifically, the potential value related to a cyanoHAB early warning system, based on potential toxicity, was analyzed that would provide information two additional days earlier relative to cyanoHAB toxicity. The evaluation considers the application of this information for freshwater lake management - whether or not to post an advisory or warning to avoid recreational water contact. The model was parameterized with data from the state of Kansas and the value of avoided foregone recreation and avoided health effects was derived. The estimated annual value of information ranges between \$565 thousand to \$2.3 million (2018 United States Dollars (USD)) for the state of Kansas alone based on provided assumptions. The results demonstrate a lower bound of the value of a cyanoHAB early warning system and suggest additional research to understand how the use and value of this information could support research prioritization and further illustrate the return on research investment. This analysis does not incorporate the full suite of potential societal costs that may be associated with a cyanoHAB event such as drinking water treatment, impacts to irrigation, or power generation.

Kansas↗
USGS2008

Effectiveness of piscicides for controlling round gobies (Neogobius melanostomus)

Round gobies (Neogobius melanostomus) were introduced to the Great Lakes presumably as a result of ballast water releases from seagoing freighters returning from European water bodies. These unwelcome fish have become established in the Great Lakes region and are expanding their range to suitable portions of other interior drainage basins including the Mississippi River traversing the central United States and the Trent-Severn waterway spanning south-central Ontario. If the invasion continues, use of chemical toxicants as a control measure may be necessary. Toxicity tests of the currently registered piscicides antimycin, rotenone, 3-trifluoromethyl-4-nitrophenol (TFM), and Bayluscide?? were conducted with three fish species native to the Great Lakes and round gobies collected from the Illinois Waterway. Tests indicated that round gobies are sensitive to all of the piscicides, however, the level of sensitivity is similar to that of the native fish species tested. Therefore, currently registered piscicides have limited potential to selectively remove round gobies. Bottom-release formulations of Bayluscide?? and antimycin were also evaluated as control agents for the normally bottom-dwelling round goby. Avoidance behavior tests demonstrated that the round goby did not react to the presence of either chemical. Therefore, the bottom-release formulations may have some application for the selective removal of round gobies, and may be one of the few tools presently available to fishery managers to help limit the range expansion of this invasive fish.

Journal of Great Lakes Research↗
USGS2009

The weathering of a sulfide orebody: Speciation and fate of some potential contaminants

Various potentially toxic trace elements such as As, Cu, Pb and Zn have been remobilized by the weathering of a sulfide orebody that was only partially mined at Leona Heights, California. As a result, this body has both natural and anthropogeni- cally modified weathering profiles only 500 m apart. The orebody is located in a heavily urbanized area in suburban Oakland, and directly affects water quality in at least one stream by producing acidic conditions and relatively high concentrations of dissolved elements (e.g., ??500 ??g/L Cu, ??3700 ??g/L Zn). Micrometric-scale mineralogical investigations were performed on the authigenic metal-bearing phases (less than 10 ??m in size) using electron-probe micro-analysis (EPMA), micro-Raman, micro X-ray absorption spectroscopy (??XAS), scanning X-ray diffraction ((??SXRD) and scanning X-ray fluorescence (??-SXRF) mapping techniques. Those measurements were coupled with classical mineralogical laboratory techniques, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Authigenic metal-bearing phases identified are mainly sulfates (jarosite, epsomite, schwertmannite), Fe (oxy-)hydroxides (goethite, hematite and poorly crystalline Fe products) and poorly crystalline Mn (hydr-)oxides. Sulfates and Fe (oxy-)hydroxides are the two main secondary products at both sites, whereas Mn (hydr-) oxides were only observed in the samples from the non-mining site. In these samples, the various trace elements show different affinities for Fe or Mn compounds. Lead is preferentially associated with Mn (hydr-)oxides and As with Fe (oxy-)hydroxides or sulfates. Copper association with Mn and Fe phases is questionable, and the results obtained rather indicate that Cu is present as individual Cu-rich grains (Cu hydroxides). Some ochreous precipitates were found at both sites and correspond to a mixture of schwertmannite, goethite and jarosite containing some potentially toxic trace elements such as Cu, Pb and Zn. According to the trace element distribution and relative abundance of the unweathered sulfides, this orebody still represents a significant reservoir of potential contaminants for the watershed, especially at the non-mining site, as a much greater proportion of sulfides is left to react and because of the lower porosity at this site.

Canadian Mineralogist↗
USGS2025

Leisure boat harbours, hidden alien species, and pollution: A case study of Hinsholmskilen harbour (Gothenburg, Sweden)

Small leisure boat harbours have important aesthetic and recreational values in any country with a coastline. In Sweden, there are about 860 000 leisure boats, which is one of the world's highest numbers in relation to the country's population. However, small boat harbours also present a wide range of environmental problems, including the introduction of alien species and high pollution. In this study, we investigated the ecological quality status (EcoQS) of the Hinsholmskilen small boat harbour, located southwest of the city of Gothenburg (Sweden). We performed a reconnaissance survey of the harbour's previously unstudied benthic foraminiferal communities and analysed surface sediment (0–2 cm) samples for potentially toxic elements: copper (Cu), zinc (Zn), lead (Pb), cobalt (Co), nickel (Ni), chromium (Cr), mercury (Hg), and arsenic (As). The results show that, based on the total benthic foraminiferal distribution (dead and live specimens), the assemblages in Hinsholmskilen harbour represent a typical European estuarine community with highly abundant Ammonia and Elphidium species. Based on molecular and morphological data, we report the presence of two alien and putatively invasive species likely originating from Asia: Trochammina hadai and Ammonia confertitesta (phylotype T6). Both species have recently been identified elsewhere on the Swedish west coast based on molecular and morphological data but do not have a well-known distribution. The sediment analysis for potentially toxic elements showed that the harbour has good to high EcoQS corresponding to no or little deviation from reference conditions for Cd, Co, Ni, and Pb distribution. Some of the contaminants (Pb, As, Zn, and Cr) showed poor to bad EcoQS in the innermost harbour in proximity to high-pressure cleaning plants, where boats are usually lifted, cleaned, and prepared for winter storage on land. Finally, Cu and Hg showed consistently bad and poor EcoQS all over the harbour, reflecting the use of both metals as biocides in antifouling boat paints.

Gothenburg↗
USGS2012

Metal dispersion resulting from mining activities in coastal environments: A pathways approach

Acid rock drainage (ARD) and disposal of tailings that result from mining activities impact coastal areas in many countries. The dispersion of metals from mine sites that are both proximal and distal to the shoreline can be examined using a pathways approach in which physical and chemical processes guide metal transport in the continuum from sources (sulfide minerals) to bioreceptors (marine biota). Large amounts of metals can be physically transported to the coastal environment by intentional or accidental release of sulfide-bearing mine tailings. Oxidation of sulfide minerals results in elevated dissolved metal concentrations in surface waters on land (producing ARD) and in pore waters of submarine tailings. Changes in pH, adsorption by insoluble secondary minerals (e.g., Fe oxyhydroxides), and precipitation of soluble salts (e.g., sulfates) affect dissolved metal fluxes. Evidence for bioaccumulation includes anomalous metal concentrations in bivalves and reef corals, and overlapping Pb isotope ratios for sulfides, shellfish, and seaweed in contaminated environments. Although bioavailability and potential toxicity are, to a large extent, functions of metal speciation, specific uptake pathways, such as adsorption from solution and ingestion of particles, also play important roles. Recent emphasis on broader ecological impacts has led to complementary methodologies involving laboratory toxicity tests and field studies of species richness and diversity.

Oceanography↗
USGS2013

Occurrence and mobility of mercury in groundwater: Chapter 5

1. Introduction 1.1. FORMS, TOXICITY, AND HEALTH EFFECTS Mercury (Hg) has long been identified as an element that is injurious, even lethal, to living organisms. Exposure to its inorganic form, mainly from elemental Hg (Hg(0)) vapor ( Fitzgerald & Lamborg, 2007 ) can cause damage to respiratory, neural, and renal systems ( Hutton, 1987 ; USEPA, 2012 ; WHO, 2012 ). The organic form, methylmercury (CH 3 Hg + ; MeHg), is substantially more toxic than the inorganic form ( Fitzgerald & Lamborg, 2007 ). Methylmercury attacks the nervous system and exposure can prove lethal, as demonstrated by well-known incidents such as those in 1956 in Minimata, Japan ( Harada, 1995 ), and 1971 in rural Iraq ( Bakir et al., 1973 ), where, in the former, industrial release of MeHg into coastal waters severely tainted the fish caught and eaten by the local population, and in the latter, grain seed treated with an organic mercurial fungicide was not planted, but eaten in bread instead. Resultant deaths are not known with certainty but have been estimated at about 100 and 500, respectively ( Hutton, 1987 ). Absent such lethal accidents, human exposure to MeHg comes mainly from ingestion of piscivorous fish in which MeHg has accumulated, with potential fetal damage ascribed to high fish diets during their mothers’ pregnancies ( USEPA, 2001 ). Lesser human exposure occurs through ingestion of drinking water (USEPA, 2001), where concentrations of total Hg (THg; inorganic plus organic forms) typically are in the low nanograms-per-liter range [1] - , particularly from many groundwater sources, and concentrations at the microgram-per-liter level are rare.

Book chapter↗
USGS2016

Evaluation of chemical control for nonnative crayfish at a warm-water fish production hatchery

Invasive crayfish are known to displace native crayfish species, alter aquatic habitat and community structure and function, and are serious pests for fish hatcheries. White River Crawfish (WRC; Procambarus acutus) were inadvertently introduced to a warm-water fish hatchery in Missouri, USA, possibly in an incoming fish shipment. We evaluated the use of chemical control for crayfish to ensure incoming and outgoing fish shipments from hatcheries do not contain live crayfish. We conducted acute (≤24 hr) static toxicity tests to determine potency, dose-response, and selectivity of pesticides to WRC, Virile Crayfish (VC; Orconectes virilis), and Fathead Minnow (FHM; Pimephales promelas). Testing identified a formulation of cypermethrin (Cynoff®) as the most potent of five pesticides evaluated for toxicity to crayfish. A 4-hr exposure to a cypermethrin concentration of 100 μg · L-1 was found to kill 100% of juvenile and adult WRC; however, adult VC were not consistently killed. Concentrations of cypermethrin ≤100 μg · L-1 did not cause significant (>10%) mortality in juvenile FHM. Additional testing is needed to examine selectivity between crayfish and hatchery fish species. Biosecurity protocols at hatcheries that use chemical control have the potential to reliably prevent inadvertent transfers of live crayfish in fish shipments.

Missouri↗
USGS2004

Zinc toxicosis in a free-flying trumpeter swan (Cygnus buccinator)

A trumpeter swan (Cygnus buccinator) was observed near it mill pond in Picher, Oklahoma. USA. It became weakened and emaciated after about 1 mo, was captured with little resistance, and taken into captivity for medical care. Serum chemistry results were consistent with hepatic, renal, and muscular damage. Serum zinc concentration was elevated at 11.2 parts per million (ppm). The swan was treated for suspected heavy-metal poisoning, but died overnight. Gross postmortem findings were emaciation and pectoral muscle atrophy. Histopathologic lesions in the pancreas included mild diffuse disruption of acinar architecture, severe diffuse depletion or absence of zymogen granules, occasional apoptotic bodies ics in acinar epithelial cells, and mild interstitial and capsular fibrosis. Zinc concentration in pancreas was 3,200 ppm wet weight, and was similar to that reported in the pancreases of waterfowl known to be killed by zinc toxicity. Zinc concentrations in liver (154 ppm) and kidneys (145 ppm) also were elevated. Acute tubular necrosis of the collecting tubules of the kidneys was also possibly due to zinc toxicity. To the authors' knowledge, this is the first confirmed case of zinc poisoning in a trumpeter swan associated with mining wastes..

Journal of Wildlife Diseases↗
USGS2010

Persistent organic pollutants in the blood of free-ranging sea otters (Enhydra lutris ssp.) in Alaska and California

As part of tagging and ecologic research efforts in 1997 and 1998, apparently healthy sea otters of four age-sex classes in six locations in Alaska and three in California were sampled for persistent organic pollutants (POPs) and other chemicals of ecologic or environmental concern (COECs). Published techniques for the detection of POPs (specifically Σpolychlorinated biphenyls [PCBs], ΣDDTs, Σhexachlorocyclohexanes [HCHs], Σpolycyclic aromatic hydrocarbons [PAHs], Σchlordanes [CHLs], hexachlorobenzene [HCB], dieldrin, and mirex) in the tissue of dead otters were modified for use with serum from live sea otters. Toxic equivalencies (TEQs) were calculated for POPs with proven bioactivity. Strong location effects were seen for most POPs and COECs; sea otters in California generally showed higher mean concentrations than those in Alaska. Differences in contaminant concentrations were detected among age and sex classes, with high levels frequently observed in subadults. Very high levels of ΣDDT were detected in male sea otters in Elkhorn Slough, California, where strong freshwater outflow from agricultural areas occurs seasonally. All contaminants except mirex differed among Alaskan locations; only ΣDDT, HCB, and chlorpyrifos differed within California. High levels of ΣPCB (particularly larger, more persistent congeners) were detected at two locations in Alaska where associations between elevated PCBs and military activity have been established, while higher PCB levels were found at all three locations in California where no point source of PCBs has been identified. Although POP and COEC concentrations in blood may be less likely to reflect total body burden, concentrations in blood of healthy animals may be more biologically relevant and less influenced by state of nutrition or perimortem factors than other tissues routinely sampled.

Alaska, California↗
USGS2003

Effects of lampricide exposure on the survival, growth, and behavior of the unionid mussels Elliptio complanata and Pyganadon cataracta

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 measured. Growth of juvenile E. complanata mussels 10 months after exposure was also compared. Toxicity was determined after 12 h exposures at maximum concentrations from 2- to 2.5- fold higher than the LC99 for sea lamprey larvae. A logistic model was used to estimate the probability of survival among treatments, trials, species, and sizes. Mortality was minimal in all test concentrations of TFM alone and the TFM/1% niclosamide combination. Estimated survival decreased 6% for each unit increase in the relative toxicity of TFM. Survival was greater for E. complanata than for P. cataracta, and for adults relative to juveniles. Lampricide treatment caused narcotization of both mussels (defined as having gaped shells and an extended foot) in concentrations greater than or equal to LC99 for sea lamprey larvae and narcotization ranged from 0-50% among treatments. Recovery from narcosis was apparent by 12 h post-exposure and complete by 36 h post-exposure. The rate of growth of E. complanata over the 10-month post-exposure period did not vary among treatments.

Journal of Great Lakes Research↗
USGS1984

Lead poisoning of sandhill cranes (Grus canadensis)

Two wild and two captive sandhill cranes ( Grus canadensis ) were diagnosed by National Wildlife Health Laboratory personnel as having died from lead toxicity. Ingestion of lead fishing weights by the wild cranes and of unspent .22 caliber shell cartridges by the captive cranes were responsible for these deaths. One crane force-fed lead pellets showed an increase of blood lead levels from 0.77 ppm to 23.8 ppm (wet weight) just before its death 15 days following exposure. Liver lead concentrations of sandhill cranes dying of causes other than lead toxicity are presented.

California, Indiana, Nebraska, Texas↗
USGS2006

Comparison of trace element concentrations in livers of diseased, emaciated and non-diseased southern sea otters from the California coast

Infectious diseases have been implicated as a cause of high rates of adult mortality in southern sea otters. Exposure to environmental contaminants can compromise the immuno-competence of animals, predisposing them to infectious diseases. In addition to organic pollutants, certain trace elements can modulate the immune system in marine mammals. Nevertheless, reports of occurrence of trace elements, including toxic heavy metals, in sea otters are not available. In this study, concentrations of 20 trace elements (V, Cr, Mn, Co, Cu, Zn, Rb, Sr, Mo, Ag, Cd, In, Sn, Sb, Cs, Ba, Hg, Tl, Pb, and Bi) were measured in livers of southern sea otters found dead along the central California coast (n = 80) from 1992 to 2002. Hepatic concentrations of trace elements were compared among sea otters that died from infectious diseases (n = 27), those that died from non-infectious causes (n = 26), and otters that died in emaciated condition with no evidence of another cause of death (n = 27). Concentrations of essential elements in sea otters varied within an order of magnitude, whereas concentrations of non-essential elements varied by two to five orders of magnitude. Hepatic concentrations of Cu and Cd were 10- to 100-fold higher in the sea otters in this study than concentrations reported for any other marine mammal species. Concentrations of Mn, Co, Zn, and Cd were elevated in the diseased and emaciated sea otters relative to the non-diseased sea otters. Elevated concentrations of essential elements such as Mn, Zn, and Co in the diseased/emaciated sea otters suggest that induction of synthesis of metallothionein and superoxide dismutase (SOD) enzyme is occurring in these animals, as a means of protecting the cells from oxidative stress-related injuries. Trace element profiles in diseased and emaciated sea otters suggest that oxidative stress mediates the perturbation of essential-element concentrations. Elevated concentrations of toxic metals such as Cd, in addition to several other organic pollutants, may contribute to oxidative stress-meditated effects in sea otters.

California↗
USGS1961

Use of 3-trifluormethyl-4-nitrophenol as a selective sea lamprey larvicide

The recent discovery of a group of chemical compounds that are significantly more toxic to sea lampreys than to other aquatic organisms offers promise of an early and effective control of this pest. The sea lamprey has all but destroyed the lake trout populations of Lakes Huron and Michigan. In Lake Superior, production of the lake trout fishery has declined to record low levels. Only a rapid and drastic reduction in sea lamprey predation can save the lake trout population there. Other species of food and game fishes have suffered severe decreases from persistent attack by the lamprey. The sea lamprey spends only a small portion of its life as a parasite in the Great Lakes. The fully grown and sexually mature adults migrate into streams to spawn and thereafter die. The eggs hatch in a week to 10 days and the larvae remain in the stream bottom for 5 years or longer before metamorphosis into the adult form. Following this transformation the young lampreys migrate downstream to the lakes to begin their parasitic existence. The life cycle of the sea lamprey has been described in detail elsewhere (Applegate 1950; Applegate and Moffett 1955). Control of the adult lampreys distributed throughout a body of open water as large as one of the Great Lakes, by known and available techniques, is not feasible. Fortunately, this pest can be attacked effectively at those stages in its life cycle when it is concentrated in restricted areas. Various devices have been developed which prevent spawning by blocking the streams below the spawning grounds. Electrical weirs, that repel or destroy the lampreys, have been used (Applegate, Smith, and Nielsen 1952; Erkkila, Smith, and McLain 1956). A serious shortcoming of this control method is the time required to achieve the desired effect. Even though the adults have been destroyed before spawning, 5 or more generations of larval lampreys are already in the stream-enough to provide an annual supply of parasitic adults for an equal period of time. Almost all the larvae of the sea lamprey live in the spawning streams. Treatment of these streams with selectively toxic chemicals that kill the larvae provides immediate reduction of all generations in the population before they become parasites. Control of the species can thus be achieved without a delay of several years.

Technical Report↗
USGS1974

Control of the sea lamprey (Petromyzon marinus) in Lake Superior, 1953-70

The sea lamprey (Petromyzon marinus) gained entrance into Lake Superior in the early 1940's, and began making drastic inroads on the fish stocks by the early 1950's. Serious efforts to control the parasite began in 1953 with the installation of electrical barriers in streams to block spawning runs. Control measures became much more effective after 1958, when a selective toxicant, the lampricide 3-trifluoromethyl-4-nitrophenol (TFM), was used to destroy larval lampreys in streams. A unique methodology was developed for stream treatments which included surveys to find sea lamprey larvae, bioassays to determine effective lampricide concentrations, analytical techniques to monitor concentrations of lampricide throughout the treatment, and feeder systems to apply the toxicant in controlled amounts. Evidence of successful control was indicated first by reduced sea lamprey spawning runs, as measured by the numbers of adults taken at electrical barriers. The runs declined in 1962 by about 86%; periodic re-treatments of lamprey-infested streams held the population at a low level in 1963-70. Other indicators of success were decreases in the incidence of sea lamprey wounds on lake trout (Salvelinus namaycush), in the numbers of sea lamprey larvae in streams, and in the number of streams regularly used by sea lampreys for spawning. Although sea lamprey control and heavy plantings of hatchery-reared stock had restored lake trout abundance to prelamprey levels in many areas by 1970, the trout had not yet become self-sustaining. Additional effort will be required to further reduce the effects of lamprey predation.

Technical Report↗
USGS1959

The reclamation of Indian and Abrams creeks in Great Smoky Mountains National Park

A complete program of stream reclamation was developed and applied on Indian and Abrams creeks in Great Smoky Mountains National Park. A salt-resistivity technique was used to estimate the dilution and velocity of a toxicant in running water. Streamside toxicity trials on resident fishes established minimal, effective concentrations of the rotenone material. The successful removals of undesirable fish were followed by restocking with selected strains of eastern brook trout and rainbow trout. Post-reclamation observations demonstrated enhanced survival, growth, reproduction, and catch of trout. Factors which might limit the effectiveness of stream reclamation programs ar e discussed.

North Carolina, Tennessee↗
USGS1990

Resistance to 3-trifluoromethyl-4-nitrophenol (TFM) in sea lamprey

The lampricide 3-trifluoromethyl-4-nitrophenol (TFM) has been used in the United States and Canada for more than 30 years to control populations of sea lamprey (Petromyzon marinus) in the Great Lakes. There is concern that sea lamprey might become resistant to TFM. Lampricide toxicity tests have been conducted at the Hammond Bay Biological Station, Millersburg, Michigan, since the 1950s and examination of TFM toxicity data for larval lamprey from 1963 to 1987 indicated that sea lamprey have not developed increased resistance to TFM. Maintenance of current control practices are unlikely to cause the development of TFM-resistant sea lamprey strains in the foreseeable future.

Technical Report↗