| mercury concentrations in fish from a sierra nevada foothill reservoir located downstream from historic gold-mining operations. | this study examined mercury concentrations in whole fish from camp far west reservoir, an 830-ha reservoir in northern california, usa, located downstream from lands mined for gold during and following the gold rush of 1848-1864. total mercury (reported as dry weight concentrations) was highest in spotted bass (mean, 0.93 microg/g; range, 0.16-4.41 microg/g) and lower in bluegill (mean, 0.45 microg/g; range, 0.22-1.96 microg/g) and threadfin shad (0.44 microg/g; range, 0.21-1.34 microg/g). spati ... | 2010 | 19283498 |
| spatiotemporal trends in fish mercury from a mine-dominated ecosystem: clear lake, california. | clear lake, california, usa, receives acid mine drainage and mercury (hg) from the sulphur bank mercury mine, a u.s. environmental protection agency (u.s. epa) superfund site that was active intermittently from 1873 to 1957 and partially remediated in 1992. mercury concentrations were analyzed primarily in four species of clear lake fishes: inland silversides (menidia beryllina, planktivore), common carp (cyprinus carpio, benthic scavenger/omnivore), channel catfish (ictalurus punctatus, benthic ... | 2008 | 19475924 |
| changes in fish diets and food web mercury bioaccumulation induced by an invasive planktivorous fish. | the invasion, boom, collapse, and reestablishment of a population of the planktivorous threadfin shad in clear lake, california, usa, were documented over a 20-year period, as were the effects of changing shad populations on diet and mercury (hg) bioaccumulation in nearshore fishes. threadfin shad competitively displaced other planktivorous fish in the lake, such as inland silversides, young-of-year (yoy) largemouth bass, and yoy bluegill, by reducing zooplankton abundance. as a result, all thre ... | 2008 | 19475926 |
| sublethal dietary effects of microcystin producing microcystis on threadfin shad, dorosoma petenense. | the presence of the toxic cyanobacterium microcystis in the upper san francisco estuary (sfe) since 1999 is a potential but unquantified threat to the health and survival of aquatic organisms such as fish and zooplankton. the microcystins (mcs) predominantly in the lr-form (mc-lr) produced by microcystis is hepatotoxic and a potential threat to the fishery. concurrently, in the sfe significant declines in pelagic fish, known as the pelagic organism decline (pod), has been recognized by state and ... | 2012 | 22925841 |
| bayesian change point analysis of abundance trends for pelagic fishes in the upper san francisco estuary. | we examined trends in abundance of four pelagic fish species (delta smelt, longfin smelt, striped bass, and threadfin shad) in the upper san francisco estuary, california, usa, over 40 years using bayesian change point models. change point models identify times of abrupt or unusual changes in absolute abundance (step changes) or in rates of change in abundance (trend changes). we coupled bayesian model selection with linear regression splines to identify biotic or abiotic covariates with the str ... | 2010 | 20666259 |
| analysis of pelagic species decline in the upper san francisco estuary using multivariate autoregressive modeling (mar). | four species of pelagic fish of particular management concern in the upper san francisco estuary, california, usa, have declined precipitously since ca. 2002: delta smelt (hypomesus transpacificus), longfin smelt (spirinchus thaleichthys), striped bass (morone saxatilis), and threadfin shad (dorosoma petenense). the estuary has been monitored since the late 1960s with extensive collection of data on the fishes, their pelagic prey, phytoplankton biomass, invasive species, and physical factors. we ... | 2010 | 20666258 |