ALBERT

Notes: Abstract As a continuing part of the National Contaminant Biomonitoring Program, the U.S. Fish and Wildlife Service collected freshwater fish at 112 monitoring stations in 1978–1979 and 1980–1981. Three composite samples of three to five fish were collected at each of about half of the stations in odd-numbered years and at the other half in even-numbered years, and analyzed for lead, mercury, cadmium, arsenic, selenium, cooper, and zinc. The geometric means, minimum, and maximum of elemental concentrations (μg/g wet weight) during 1978–1979 and (in parentheses) during 1980–1981 were as follows: Pb 0.19, 0.10–6.73 (0.17, 0.10–1.94); Hg 0.11, 0.01–1.10 (0.11, 0.01–0.77); Cd 0.04, 0.01–0.41 (0.03, 0.01–0.35); As 0.16, 0.04–2.08 (0.14, 0.05–1.69); Se 0.46, 0.09–3.65 (0.47, 0.09–2.47); Cu 0.86, 0.29–38.75 (0.68, 0.25–24.10); and Zn 25.63, 7.69–168.1 (23.82, 8.82–109.2). The 85th percentile, calculated for station mean concentrations (μg/g wet weight) for 1978–1979 and 1980–1981, respectively, were: Pb 0.32 and 0.25; Hg 0.18 and 0.18; Cd 0.09 and 0.06; As 0.23 and 0.22; Se 0.70 and 0.71; Cu 1.14 and 0.90; and Zn 46.26 and 40.09. There was no significant upward or downward trend between collection periods of the national geometric means of any of the elements except for cooper which decreased significantly. Species differences in elemental concentrations contributed more variability to the data set than did station differences. The proportion of the collections composed of each species changed little between collection periods. Thus, the magnitude of the species effect on the national geometric mean of each period was probably fairly consistent; however, it precludes our making sound comparisons among various regions of the United States. As a participant in the National Contaminant Biomonitoring Program (NCBP), the U.S. Fish and Wild-life Service is responsible for monitoring temporal and geographic trends of organochlorine chemical and elemental contaminants in the nation's fresh-water fish, European starlings (Sturnus vulgaris), and waterfowl. Primary emphasis has been placed on organochlorine chemical contaminants; however, certain elements have been measured intermittently and additional elements have been added periodically since 1969. We summarize the concentrations of the seven elements—lead, mercury, cadmium, arsenic, selenium, copper, and zinc—measured in freshwater fish collected during 1978–1981. Data for earlier collections have appeared in other reports (Hendersonet al. 1972; May and McKinney 1981; Walshet al. 1977).

Notes: Abstract Survival of anuran embryos and tadpoles is reduced in acidic (pH〈5.0) waters under laboratory conditions. However, field data on the presence-absence of amphibian species and acidity are equivocal. This study attempts to reconcile some of this discrepancy by using macrocosms to examine the interaction of soil type and water acidification on free-ranging tadpole populations. Tadpoles were caught with activity traps in 24 aquatic macrocosms experimentally treated with H2SO4 and Al2(SO4)3 and lined with either comparatively high metal, low organic matter clay soils or lower metal, higher organic matter loams. Northern cricket frog (Acris crepitans) tadpole abundance was less in acidified macrocosms than in circumneutral ones (p〈0.05) and less in those with loam soils than in macrocosms with clay soils (p〈0.04). Gray treefrog (Hyla versicolor) abundance was affected by an interaction between soil and acidification (p〈0.07) in that treatment effects were only observed in macrocosms with clay soils (p〈0.01). No differences were observed among treatments for green frog (Rana clamitans) or southern leopard frog (R. utricularia) tadpoles. The study shows that soil type may interact with water conditions to affect amphibian populations in acidified waters.