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Objective: To describe coronavirus disease 2019 (COVID‐19) mitigation measures in workplaces of employed US blood donors by industry and work arrangement. Methods: During May–December 2021, blood donors responded to a survey; we describe the distribution of reported workplace mitigation measures by industry and work arrangement, organized using the hierarchy of controls. Results.: Of 53,433 respondents representing 21 industries, ventilation upgrades were reported by 4%–38% of respondents (overall: 20%); telework access ranged from 14%–80% (53% overall). Requiring masks (overall: 84%; range: 40%–94%), physical distancing (77%; 51%–86%), paid leave for illness (70%; 38%–87%), and encouraging vaccination (61%; 33%–80%) were common. Independent workers reported fewer mitigation measures than those in traditional employment settings. Conclusions: Mitigation measures varied by industry and work arrangement. Some mitigation measures may be challenging to implement or irrelevant in certain industries, supporting the idea that mitigation is not a one‐size‐fits‐all strategy. Policy Implications: Tailored strategies to mitigate workplace risks of disease transmission are vital. Strategies should rely on effective methods for identifying workplace controls (e.g., through the hierarchy of controls) and account for industry‐specific characteristics and workplace environments. [ABSTRACT FROM AUTHOR]

Background: Work is a social determinant of health that is often overlooked. There are major work‐related differences in the risk of severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) infection and death, but there have been few analyses of infection rates across industry groups. To date, only one national assessment of SARS‐CoV‐2 infection prevalence by industry based on self‐report has been completed. No study has looked at seroprevalence of COVID‐19 by industry. Methods: During May–December 2021, blood donors with SARS‐CoV‐2 antinucleocapsid testing were sent an electronic survey about their work. Free‐text industry responses were classified using the North American Industry Classification System. We estimated seroprevalence and 95% confidence intervals (CIs) of SARS‐CoV‐2 infection by industry. Results: Of 57,726 donors, 7040 (12%, 95% CI: 11.9%−12.5%) had prior SARS‐CoV‐2 infection. Seroprevalence was highest among Accommodation & Food Services (19.3%, 95% CI: 17.1%−21.6%), Mining, Quarrying, and Oil and Gas Extraction (19.2%, 95% CI: 12.8%−27.8%), Healthcare & Social Assistance (15.6%, 95% CI: 14.9%−16.4%), and Construction (14.7%, 95% CI: 13.1%−16.3%). Seroprevalence was lowest among Management of Companies & Enterprises (6.5%, 95% CI: 3.5%−11.5%), Professional Scientific & Technical Services (8.4%, 95% CI: 7.7%−9.0%), and Information (9.9%, 95% CI: 8.5%−11.5%). Conclusions: While workers in all industries had serologic evidence of SARS‐CoV‐2 infection, certain sectors were disproportionately impacted. Disease surveillance systems should routinely collect work characteristics so public health and industry leaders can address health disparities using sector‐specific policies. [ABSTRACT FROM AUTHOR]

The Northern Sunfish (Lepomis peltastes Cope, 1870) is threatened in New York state, USA, but this was not the case before 1940 when the NY Biological Survey documented the species at scattered, specialized habitats in six watersheds in the central and western parts of the state. After 1940 the historic populations could not be detected, but a new population was discovered in 1974 in lower Tonawanda Creek and the nearby Erie Canal. Northern Sunfish, and a few of their hybrids with other Lepomis species, were caught at these locations during irregular sampling through 2009, but no Northern Sunfish were caught after 2009. The objectives of our study were to: (1) Determine the extent of Northern Sunfish hybridization with other Lepomis species, and (2) Evaluate how well identifications of Lepomis species and their hybrids agreed among field keys, morphometric measurements and meristic counts, and genetic methods. In 2013, we collected Northern Sunfish (descended from fish captured in lower Tonawanda Creek from 2006-2009) from NY State Department of Environmental Conservation rearing ponds, plus wild Green Sunfish (L. cyanellus Rafinesque, 1819), Pumpkinseed (L. gibbosus Linnaeus, 1758), Bluegill (L. macrochirus Rafinesque, 1819), and suspected Lepomis hybrids from lower Tonawanda Creek. Ultimately, 91 fish were identified using field keys, morphometric-meristic analysis, and mtDNA and nuclear DNA analysis. Assuming genetic analysis provided accurate identification, we found 7 Bluegill × Northern Sunfish, 8 Bluegill × Pumpkinseed, 13 Bluegill × Green Sunfish, and 3 Green Sunfish × Pumpkinseed hybrids in our sample (female parent listed second in these crosses). Keyed and morphometric-meristic identifications did not differ in accuracy and averaged 81% of genetic identification accuracy. After Northern Sunfish stocking (not in our study area) and sampling from 2008 to 2018 in several watersheds with appropriate habitat and no recaptures after 2014, we conclude that the Northern Sunfish is extirpated in western New York state. While populations of Northern Sunfish (Lepomis peltastes) existed in several New York state watersheds before 1940, only one, discovered in 1974, persisted in small areas of lower Tonawanda Creek and the nearby Erie Canal. Despite high effort, no Northern Sunfish were captured after 2009 in the places they had occupied since 1974. Because many Northern Sunfish, all descended from wild fish in lower Tonawanda Creek and the Erie Canal, exist in two New York state hatchery ponds, we recommend attempting restoration in their former habitat by stocking. [ABSTRACT FROM AUTHOR]

We evaluated antibodies to the nucleocapsid protein of SARS-CoV-2 in a large cohort of blood donors in the United States who were recently infected with the virus. Antibodies to the nucleocapsid protein of SARS-CoV-2 indicate previous infection but are subject to waning, potentially affecting epidemiologic studies. We longitudinally evaluated a cohort of 19,323 blood donors who had evidence of recent infection by using a widely available serologic test to determine the dynamics of such waning. We analyzed overall signal-to-cutoff values for 48,330 donations (average 2.5 donations/person) that had an average observation period of 102 days. The observed peak signal-to-cutoff value varied widely, but the waning rate was consistent across the range, with a halflife of 122 days. Within the cohort, only 0.75% of persons became seronegative. Factors predictive of higher peak values and longer time to seroreversion included increasing age, male sex, higher body mass index, and non-Caucasian race. [ABSTRACT FROM AUTHOR]

Background: U.S. blood donors are tested at each donation for human T‐lymphotropic virus (HTLV) antibodies. Depending on donor incidence and other mitigation/removal technologies, a strategy of one‐time selective donor testing should be considered. Methods: Antibody seroprevalence was calculated for HTLV‐confirmed‐positive American Red Cross allogeneic blood donors from 2008 to 2021. Incidence was estimated for seven 2‐year time periods using confirmed‐positive repeat donors having seroconverted in 730 days. Leukoreduction failure rates were obtained from internal data from July 1, 2008–June 30, 2021. Residual risks were calculated using a 51‐day window period. Results: Between 2008 and 2021, >75 million donations (>18 million donors) yielded 1550 HTLV seropositives. HTLV seroprevalence was 2.05 antibody‐positives per 100,000 donations (0.77 HTLV‐1, 1.03 HTLV‐2, 0.24 HTLV‐1/2), and 10.32 per 100,000 among >13.9 million first‐time donors. Seroprevalence differed significantly by virus type, sex, age, race/ethnicity, donor status, and U.S. census region. Over 14 years and 24.8 million person‐years of observation, 57 incident donors were identified (25 HTLV‐1, 23 HTLV‐2, and 9 HTLV‐1/2). Incidence decreased from 0.30 (13 cases) in 2008–2009 to 0.25 (7 cases) in 2020–2021. Female donors accounted for most incident cases (47 vs. 10 males). In the last 2‐year reporting period, the residual risk was 1 per 2.8 million donations and 1 per 3.3 billion donations when coupled with successful leukoreduction (0.085% failure rate). Conclusions: HTLV donation seroprevalence for the years 2008–2021 varied by virus type and donor characteristics. Low HTLV residual risk and use of leukoreduction processes support the conclusion that a selective one‐time donor testing strategy should be considered. [ABSTRACT FROM AUTHOR]

Background There are limited data on the risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in the United States by occupation. We identified occupations at higher risk for prior SARS-CoV-2 infection as defined by the presence of infection-induced antibodies among US blood donors. Methods Using a nested case-control study design, blood donors during May–December 2021 with anti-nucleocapsid (anti-N) testing were sent an electronic survey on employment status, vaccination, and occupation. The association between previous SARS-CoV-2 infection and occupation-specific in-person work was estimated using multivariable logistic regression adjusting for sex, age, month of donation, race and ethnicity, education, vaccination, and telework. Results Among 85 986 included survey respondents, 9504 (11.1%) were anti-N reactive. Healthcare support (20.3%), protective service (19.9%), and food preparation and serving related occupations (19.7%) had the highest proportion of prior infection. After adjustment, prior SARS-CoV-2 infection was associated with healthcare practitioners (adjusted odds ratio [aOR], 2.10; 95% confidence interval [CI], 1.74–2.54) and healthcare support (aOR, 1.82; 95% CI, 1.39–2.40) occupations compared with computer and mathematical occupations as the referent group. Lack of coronavirus disease 2019 vaccination (aOR, 16.13; 95% CI, 15.01–17.34) and never teleworking (aOR, 1.17; 95% CI, 1.05–1.30) were also independently associated with prior SARS-CoV-2 infection. Construction and extraction occupations had the highest proportion of unvaccinated workers (30.5%). Conclusions Workers in healthcare, protective services, and food preparation had the highest prevalence of prior SARS-CoV-2 infection. Occupational risks for SARS-CoV-2 infection remained after adjusting for vaccination, telework, and demographic factors. These findings underscore the need for mitigation measures and personal protection in healthcare settings and other workplaces. [ABSTRACT FROM AUTHOR]

Background Blood donors were tested for antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2); resulting antibody levels were monitored over time. Methods Donors reactive to anti-SARS-CoV-2 spike protein (S1-total antibodies) participated in a follow-up study of 18 months. Testing for nucleocapsid antibodies distinguished between vaccination and infection. Vaccination and symptom information were collected for anti-S1-reactive donors by completing a survey. Results The majority of 249 followed donors were over 60 years old (54%), White (90%), and female (58%); 83% had not been vaccinated at enrollment, but by study completion, only 29% remained nonvaccinated. Of the 210 (84%) anti-N-reactive donors, 138 (66%) reported vaccination, whereas 37 (95%) of donors vaccinated and anti-N negative at enrollment remained uninfected. Vaccinated (2 doses) and infected donors showed a steady increase in anti-S1 that increased markedly for vaccinated donors after a booster and infected donors after vaccination (slightly higher for those with hybrid immunity), whereas anti-N levels declined. Most surveyed nonvaccinated donors (65%) reported symptoms, whereas 85% of vaccinated donors were asymptomatic. A coronavirus disease 2019 (COVID-19) diagnosis was reported by 48 (31%) nonvaccinated and 3 (8%) vaccinated donors. Of asymptomatic donors, 38% never tested diagnostically for COVID-19, and 35% tested negative, suggesting an absence of knowledge of the infection. Conclusions Healthy blood donors were vaccinated at high rates and remained mostly asymptomatic and noninfected, whereas approximately two thirds of infected donors reported symptoms. Anti-S1 levels increased while anti-N decreased over 18 months but remained comparable between vaccinated and hybrid immune individuals with dramatic anti-S1 increases after vaccination or boosting. [ABSTRACT FROM AUTHOR]

Background: A national serosurvey of U.S. blood donors conducted in partnership with the Centers for Disease Control and Prevention (CDC) was initiated to estimate the prevalence of SARS‐CoV‐2 infections and vaccinations. Methods: Beginning in July 2020, the Nationwide Blood Donor Seroprevalence Study collaborated with multiple blood collection organizations, testing labs, and leadership from government partners to capture, test, and analyze approximately 150,000 blood donation specimens per month in a repeated, cross‐sectional seroprevalence survey. Results: A CDC website (https://covid.cdc.gov/covid-data-tracker/#nationwide-blood-donor-seroprevalence) provided stratified, population‐level results to public health professionals and the general public. Discussion: The study adapted operations as the pandemic evolved, changing specimen flow and testing algorithms, and collecting additional data elements in response to changing policies on universal blood donation screening and administration of SARS‐CoV‐2 spike‐based vaccines. The national serosurvey demonstrated the utility of serosurveillance testing of residual blood donations and highlighted the role of the blood collection industry in public–private partnerships during a public health emergency. [ABSTRACT FROM AUTHOR]

Background: Most single-donor platelet (SDP) donors transition to plateletpheresis after prior red blood cell (RBC) donation. Recruitment may follow identification of a high platelet count, a marker associated with iron depletion (ID). SDP donors may have underrecognized risk for iron depletion.Study Design and Methods: To assess the prevalence of ID, we performed ferritin testing on male plateletpheresis donors with hemoglobin levels less than 13.5 g/dL. Multivariable logistic regression identified risk factors for low ferritin (LF; ferritin ≤26 ng/mL) and absent iron stores (AIS; ferritin <12 ng/mL). To assess the impact of notifying donors of LF results, we compared donation behavior of "Test" subjects before and after sending an LF notification letter to that of "Control" subjects before and after increasing the minimum hemoglobin for male donors. An electronic survey to Test donors inquired about iron supplementation practices.Results: Prevalence of LF was 50% and AIS was 23%, with increase in risk associated with more frequent SDP donation, both controlling for RBC donation and in donors with no recent RBC donations. Donation frequency after intervention declined less in 1272 Test donors (19%, from 13.9 to 11.2 annualized donations) than in 878 Control donors (49%, from 12.3 to 6.3 donations). Only 20% of Test donors reported taking supplemental iron when they received the LF letter; 64% of those not taking iron initiated iron supplementation following the letter.Conclusions: Donors were responsive to notification of LF and attendant messaging on iron supplementation. Ferritin testing potentially benefits donor health and a stable platelet supply. [ABSTRACT FROM AUTHOR]

Describes a course which focuses student activities on the preparation of an environmental impact statement. The course provides undergraduate/graduate students with an intensive field ecology experience which exposes them to scientific principles of biology, environmental analysis, and quantitative sampling methods. Includes course format, activities, and evaluation. (JN)

Background: Babesia microti, an intraerythrocytic parasite endemic in the Northeast and upper Midwest United States, is responsible for over 200 reported cases of transfusion-transmitted babesiosis (TTB). The American Red Cross has prospectively screened donations in endemic areas for B. microti since 2012.Methods: Blood donation samples from Massachusetts, Connecticut, Minnesota, and Wisconsin were tested by arrayed fluorescence immunoassay and real-time polymerase chain reaction. Donors with reactive results by any test were deferred and invited to participate in a follow-up study.Results: Screening of 506,540 donations (June 2012-May 2018) yielded 1299 reactives, 177 of which were DNA and antibody positive and 25 DNA positive only. During the same time, 23 unscreened RBC units collected in Connecticut and Massachusetts were involved in TTB cases, making the risk of transmitting the infection from an unscreened donation in these two states 15.6-times greater than from a Babesia-negative unit. B. microti screening in Connecticut and Massachusetts has been associated with a reduction in TTB cases; none reported from blood donors residing in Connecticut since 2016. The positive donor rate has also decreased in Connecticut from 0.67% in 2013 to 0.23% in 2017. Ongoing follow-up testing has shown that only 10% of antibody-positive donors serorevert within 1 year, while 94% of polymerase chain reacton-positive donors become negative within 12 months.Conclusions: Blood donation screening for B. microti in endemic areas effectively mitigates TTB risk. Screening should be considered for all areas demonstrating ongoing risk defined as clinical cases or positive blood donors including those associated with TTB cases. [ABSTRACT FROM AUTHOR]

Beginning in the mid-1980s, the Laurentian Great Lakes underwent successive invasions by Ponto-Caspian species. We quantified major changes in the diversity and relative abundance of pre-invasion benthic macroinvertebrates at the same study site in southwestern Lake Ontario from 1983-2014. The zebra mussel Dreissena polymorpha Pallas arrived at the study site before 1991, the quagga mussel Dreissena rostriformis bugensis Andrusov and the amphipod Echinogammarus ischnus Stebbing arrived before 1999, and the Round Goby Neogobius melanostomus Pallas arrived about 2004. The macroinvertebrate community in 2014 was very different from 3 earlier communities in 1983, 1991, and 1999. In 2014, pulmonate and prosobranch snails and sphaeriid bivalves were absent, D. r. bugensis replaced D. polymorpha, E. ischnus replaced Gammarus fasciatus Say as the dominant amphipod, and a previously diverse community of benthic fish was replaced by abundant N. melanostomus. From 1983 to 1999, the relative abundance of prosobranchs and pulmonates declined 10-fold and rose 2-fold, respectively. From 1991 to 2014, the relative abundance of oligochaetes and chironomids increased 32- and 78-fold, respectively. The shifts we report probably are attributable to nutrient enrichment of the nearshore of Lake Ontario during the 1990s leading to a thick carpet of macroalgae, a change in the base of the benthic food web from dressenid feces and pseudofeces to macroalgal detritus, and predation by N. melanostomus on snails. [ABSTRACT FROM AUTHOR]

San Salvador Island in The Bahamas is home to approximately 1,200 people, and a popular vacation destination. In order to expand our knowledge of the bacterial population found on and around the island, and to assess possible health risks, we analyzed and identified the cultivable bacterial population found in several lakes and ponds throughout the island. The sites tested were located on the northern, north-eastern, eastern, and western districts, as well as one lake located inland. Ten sites with varying salinity, levels of oxygen, visibility, and distance from the ocean were analyzed. The nature of the bacteria present in these sites was identified by microscopy, as well as a series of biochemical tests based on bacterial metabolism. Seven bacterial species, predominantly from the genera Staphylococcus and Klebsiella were identified. Most bacteria identified are part of the normal microbiota of the skin and the gastro-intestinal tract of human and mammals, and should not be considered a danger for the health of the majority of the population and tourists of the island. We also isolated bacteria capable of fixing atmospheric nitrogen, a hallmark of marine bacterial populations. Overall, this study enabled us to add to the repertoire of bacterial species isolated and identified in the diverse marine environments found on San Salvador Island. [ABSTRACT FROM AUTHOR]

The red lionfish, Pterois volitans, was first reported at San Salvador, Bahamas in January 2006; by 2009 they were common in waters 2 to 40 m deep around the island. Among the 5,078 fish observed on shallow patch reefs in 2007, only two were P. volitans; they were much more prevalent in deeper water along San Salvador's platform wall. Captured P. volitans ranged in size from 19-32 cm, all longer than maturity length. Pallid goby (Coryphopterus eidolon), blackcap basslet (Gramma melacara) and red night shrimp (Rynchocienetes rigens) were the most commonly identified stomach contents. Our study in 2007 also collected data on coral and fish communities at three, near-shore patch reef complexes (Rice Bay, Rocky Point, Lindsay Reef, and compared the results to a similar study done in 2001, before P. volitans was discovered at San Salvador. Scleractinian and, therefore, total coral species richness decreased significantly from 2001 to 2007; however, coral percentage cover increased significantly by approximately 50% during the same period, probably due to a more precise estimation procedure rather than a real increase. Even after adjustment for CPUE (2.25 more effort in 2007 than in 2001), significantly more fish were observed in 2007 than in 2001. Continued monitoring of lionfish numbers and potentially associated changes in patch reef ecology is recommended. [ABSTRACT FROM AUTHOR]

This project assessed the significance of Pigeon Creek, San Salvador, Bahamas as a nursery habitat for coral reef fishes. Pigeon Creek's perimeter is lined with mangrove and limestone bedrock. The bottom is sand or sea grass and ranges in depth from exposed at low tide to a 3-m deep, tide-scoured channel. In June 2006 and January 2007, fish were counted and their maturity was recorded while sampling 112 of 309 possible 50-m transects along the perimeter of the Pigeon Creek. Excluding silversides (Atherinidae, 52% of fish counted), six families each comprised more than 1% of the total abundance (Scaridae/parrotfishes, 35.3%; Lutjanidae/snappers, 23.9%; Haemulidae/grunts, 21.0%; Gerreidae/mojarras, 8.5%; Pomacentridae/damselfishes, 6.1%; Labridae/wrasses, 2.4%). There were few differences in effort-adjusted counts among habitats (mangrove, bedrock, mixed), sections (north, middle, southwest) and seasons (summer 2006 and winter 2007). Red mangrove (Rhizophora mangle), covering 68% of the perimeter was where 62% of the fish were counted. Snappers, grunts and parrot fishes are important food fishes and significant families in terms of reef ecology around San Salvador. Mangrove was the most important habitat for snappers and grunts; bedrock was most important for parrot fishes. The southwest section was important for snappers, grunts and parrot fishes, the north section for grunts and parrot fishes, and the middle section for snappers. Among the non-silverside fish counted, 91.2% were juveniles. These results suggest that Pigeon Creek is an important nursery for the coral reefs surrounding San Salvador and should be protected from potential disturbances. [ABSTRACT FROM AUTHOR]

Over eight million walleye (Sander vitreus) fry are stocked annually in Honeoye Lake, a small lake in the Finger Lakes region of west-central New York. The objectives of our study were to find and describe the spawning locations and habitats of walleye and to assess natural production of fry. Twenty-three adult walleye were radio-tagged and tracked for up to 2.5 years. They established relatively small home ranges (24-188 ha) and moved more during the three-week spawning season (149 m/d) than the rest of the year (37 m/d). No naturally produced walleye eggs were collected in the Honeoye Lake inlet channel where adults congregated during the 2002 and 2003 spawning seasons, nor were fry collected in the lake until after 8.7 million were stocked in 2003. Radio-tagged walleye exhibited homing and site fidelity in Honeoye Lake but not to the few known areas with suitable spawning substrates (no eggs were collected at these locations). [ABSTRACT FROM AUTHOR]

The article reports on a study which measured the abundance and diversity of corals and fishes at three patch reef complexes near San Salvador, Bahamas. The relationships among species and ecological measures coral and fish community structure were investigated. Results indicated relationships between coral and fish species at each reef. Reefs with the most coral cover had the highest number of species.

We explored the foraging ability of rock bass (Ambloplites rupestris) by testing three hypotheses consistent with the predictions of optimal foraging theory: 1) fish can learn to associate food with a visual cue; 2) trained fish will go to a visual cue faster than untrained fish: and 3) over time, without the reinforcement of food, trained fish will exhibit a diminished response to a visual cue. Our results supported each hypothesis. During the first 96 h of testing, 88 to 100% of trained fish went to the visual cue fast; 50% of the trained fish went to the visual cue first after 312 h. None of the untrained fish went to the visual cue fast. Trained fish went to the visual cue significantly faster (11.0 cm sec-1) than untrained (1.6 cm sec-1) fish. There were no significant differences in velocity to the visual cue among the times tested for control fish (0.8 to 2.6 cm sec-1). However, velocities of experimental fish were significantly higher from 0 to 24 h (16.7 cm sec-1) than from 48 to 312 h (6.7 cm sec-1), suggesting that they began extinguishing their responses as the time since the last food reward associated with the cue increased. If rock bass use these abilities in their natural habitats, they likely improve their foraging efficiency and, thus, their overall fitness. [ABSTRACT FROM AUTHOR]

The objective of our study was to collect age, growth, and catch-per-unit-effort information from a new or recovering population of lake sturgeon Acipenser fulvescens in the lower Niagara River, New York. From July 1998 through August 2000, we captured 67 lake sturgeon by use of gill nets, baited setlines, and scuba diving. Active capture by scuba divers (1.50 fish/ h) was much more effective than passive capture with gill nets (0.07 fish/h) and setlines (0.06 fish/h). Eggs of Chinook salmon Oncorhynchus tshawytscha were more effective as setline bait than were alewives Alosa pseudoharengus, but neither bait differed in effectiveness from rainbow smelt Osmerus mordax. Ages of captured lake sturgeon ranged from 1 to 23 years; 47 of the 61 aged fish were younger than age 10. Strong relationships were found between weight, W, and length, L (W = 0.0000005 · L3.5564; R² = 0.977) and between L and age (L = 394.05 · loge[age] + 248.77; R² = 0.878). The lake sturgeon population in the lower Niagara River is probably small relative to its historic abundance. This naturally reproducing population should remain listed as threatened by New York State, and commercial and recreational fisheries should remain closed so that the population can rebuild adult numbers and reproductive potential. [ABSTRACT FROM AUTHOR]

The objective of our study was to determine habitat conditions in a stream where walleye successfully produce fry and to compare these conditions with the nationally-applicable Habitat Suitability Index (HSI) model for walleye. During 17–20 d migration periods in April of 1996, 1997 and 2000, walleye were observed spawning; eggs were collected primarily in April and fry primarily in May. Water depths, velocities, and temperatures where walleyes spawned were at the lower end of or below the optimum ranges specified in the HSI for spawning walleye. However, random sampling indicated that optimum HSI conditions for these parameters generally did not exist in the stream. Substrate, dissolved oxygen, and pH were optimal according to the HSI. Our results indicate that predictions using the HSI alone are not sufficient to identify regional tributaries where walleye can successfully establish viable populations. [ABSTRACT FROM PUBLISHER]

Using video traps, we tested the commonly held view that Mink, Neovison vison, are mostly noctumal. We compared Mink passages during daylight and darkness in two habitats. Mink were significantly more nocturnal in uplands with streams and significantly more diurnal in wetlands. Assuming that uplands have a higher proportion of terrestrial prey active at night and wetlands have a higher proportion of aquatic prey, the observed difference in activity periods may be related to the difficulty of seeing aquatic prey at night and suggests a dynamic interaction between food visibility and diel activity in Mink. [ABSTRACT FROM AUTHOR]

The New York State Erie Barge Canal was first colonized by the zebramussel (Dreissena polymorpha) in 1989. Canal water supplements flowsin many creeks in western New York, including six creeks in Monroe County that have not been colonized by zebra mussels. We chose Salmon Creek to study why zebra mussels have not colonized regional creeks because the rocky substrate of the creek appears ideal for colonization, yet 100 meters downstream from the input of canal water to the creek adult zebra mussel densities drop to less than one mussel m{sup}-2{end}. In the summer of 1993, veliger counts in the canal averaged 52times greater than they were in Salmon Creek yet water quality, current velocity, and particulate organic carbon concentrations in the creek and the canal were very similar. Chlorophyll a in the canal was higher than in the creek. Given the appropriate physical habitat and water quality conditions and an abundant source of veligers, the factors limiting zebra mussel colonization in Salmon Creek remain unknown,but three factors appear important: 1) Partial retention of zebra mussel veligers by the wetland through which the canal discharge flows,2) Filtering of phytoplankton and veligers by the dense bed of adultzebra mussels at the beginning of the outfall channel from the canalto the creek, or 3) Inappropriate food quality (e.g., lack of phytoplankton with important fatty acid constituents) in the creek. [ABSTRACT FROM AUTHOR]