Seasonal and annual trends in forage fish mercury concentrations, San Francisco Bay

Greenfield, B. K.; Melwani, A. R.; Allen, Rachel M.; Slotton, Darell G.; Ayers, Shaun M.; Harrold, K. H.; Ridolfi, K.; Jahn, Andrew E.; Grenier, J. Letitia; Sandheinrich, Mark B.

doi:10.1016/j.scitotenv.2012.12.009

Cited by 20 publications

(19 citation statements)

References 49 publications

(86 reference statements)

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“…For example, as observed in our study, lower mercury concentrations were observed in winter than in spring in the Mississippi silverside (Menidia audens) collected in San Francisco Bay, but this pattern differed depending on the site (Greenfield et al 2013b). In the literature, seasonal variations in Hg species concentrations are usually related to different patterns in net mercury methylation in the sediment or water column (Gorski et al 1999;Heim et al 2007;Stoichev et al 2004).…”

Section: Temporal Variationsupporting

confidence: 74%

“…A number of studies, dealing with sediment and forage fish monitoring, reported seasonal variation in Hg concentrations which might be consistent (Eagles-Smith and Ackerman 2009;Zhang et al 2012) or fluctuate depending on the site and/or the year (Greenfield et al 2013b). For example, as observed in our study, lower mercury concentrations were observed in winter than in spring in the Mississippi silverside (Menidia audens) collected in San Francisco Bay, but this pattern differed depending on the site (Greenfield et al 2013b).…”

Section: Temporal Variationsupporting

confidence: 73%

“…Finally, it is noteworthy that a similar pattern of interannual variation was observed between the marine and estuarine sites, while in San Francisco Bay, inter-annual patterns of MeHg concentrations varied considerably among site and species (Greenfield et al 2013b). This supports the idea of a weak bioaccumulation of MeHg in glass eels during their migration in the Adour estuary but also raises the question of the source of contamination that might explain MeHg concentration values observed in glass eels.…”

Section: Temporal Variationmentioning

confidence: 53%

“…The weight in glass eels is known to show seasonal fluctuation, probably because of different trophic resources during the oceanic migration of the leptocephalus larvae, but seasonal variations in MeHg concentrations have never been investigated. Several authors have reported consistent or distinct seasonal and annual variations of mercury concentrations in fish depending on species and sites (Eagles-Smith and Ackerman 2009; Greenfield and Jahn 2010, 2013bZhang et al 2012). These variations might result from changes in MeHg production, different growth patterns or behaviour, temporary anthropogenic activities and/or climatic events.…”

Section: Introductionmentioning

confidence: 94%

“…These results were only weakly explained by weight (15 % for marine and 18 % for estuarine individuals), while year explained up to 40 % of the results. Inter-annual fluctuations have been hypothesized to result from fish movement behaviour, extreme weather events or temporary management activities resulting in variations in MeHg exposure (Greenfield et al 2005(Greenfield et al , 2013b. Such seasonal variation might also result from temporal variability of MeHg production in the sediment (Stoichev et al 2004), but a long-term survey of MeHg concentrations in glass eels and sediment might provide a better understanding of the bioaccumulation of MeHg in glass eels during estuarine migration.…”

Section: Temporal Variationmentioning

confidence: 99%

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Spatial and seasonal variations of methylmercury in European glass eels (Anguilla anguilla) in the Adour estuary (France) and relation to their migratory behaviour

Claveau

Monperrus

Jarry

et al. 2015

Environ Sci Pollut Res

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Overall recruitment of European glass eels (Anguilla anguilla) has decreased significantly since the early 1980s. Due to their long life cycle, benthic/demersal habits and high lipid content, eels might accumulate high concentrations of contaminants, but data concerning glass eels are still scarce. This study provides original data on methylmercury (MeHg) concentrations in glass eels at spatial (marine and estuarine), annual and seasonal scales. The relationship between MeHg concentrations in glass eels and their propensity to migrate up estuaries was also investigated. MeHg data were individually related to the eels' energetic condition which was estimated by dry weight. Glass eel migratory behaviour was investigated in an experimental flume and related to the MeHg concentration and dry weight at the individual scale. Marine and estuarine glass eels were caught from 2004 to 2011. There was a strong inverse correlation between MeHg concentrations and dry weight. MeHg concentrations increased in marine and estuarine glass eels from 2004 to 2009 and from 2004 to 2010, respectively, and then, both groups decreased in 2011. On a seasonal time scale, MeHg concentrations were higher at the end of the fishing season (April). MeHg bioaccumulation is likely to result from different sources, but the lack of significant differences between marine and estuarine glass eels suggests that direct contamination during estuarine migration is low. Other sources such as maternal transfer or oceanic contamination are discussed.

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Section: Temporal Variationsupporting

confidence: 74%

Section: Temporal Variationsupporting

confidence: 73%

Section: Temporal Variationmentioning

confidence: 53%

Section: Introductionmentioning

confidence: 94%

Section: Temporal Variationmentioning

confidence: 99%

See 3 more Smart Citations

Spatial and seasonal variations of methylmercury in European glass eels (Anguilla anguilla) in the Adour estuary (France) and relation to their migratory behaviour

Claveau

Monperrus

Jarry

et al. 2015

Environ Sci Pollut Res

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Predictors of mercury spatial patterns in San Francisco Bay forage fish

Greenfield

Slotton²,

Harrold

2013

Enviro Toxic and Chemistry

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Pollution reduction efforts should be targeted toward those sources that result in the highest bioaccumulation. For mercury (Hg) in estuaries and other complex water bodies, carefully designed biosentinel monitoring programs can help identify predictors of bioaccumulation and inform management priorities for source reduction. This study employed a probabilistic forage fish Hg survey with hypothesis testing in San Francisco Bay (California, USA). The goal was to determine what pollution sources, regions, and landscape features were associated with elevated Hg bioaccumulation. Across 99 sites, whole-body Hg concentrations in Mississippi silversides (Menidia audens) and topsmelt (Atherinops affinis) followed a broad spatial gradient, declining with distance from the Guadalupe River (Pearson's r = -0.69 and -0.42, respectively), which drains historic mining areas. Site landscape attributes and local Hg sources had subtle effects, which differed between fish species. Topsmelt Hg increased in embayment sites (i.e., enclosed sites including channels, creek mouths, marinas, and coves) and sites with historic Hg-contaminated sediment, suggesting an influence of legacy industrial and mining contamination. In 2008, Mississippi silverside Hg was reduced at sites draining wastewater-treatment plants. Fish Hg was not related to abundance of surrounding wetland cover but was elevated in some watersheds draining from historic Hg-mining operations. Results indicated both regional and site-specific influences for Hg bioaccumulation in San Francisco Bay, including legacy contamination and proximity to treated wastewater discharge.

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Historical and Contemporary Patterns of Mercury in a Hydroelectric Reservoir and Downstream Fishery: Concentration Decline in Water and Fishes

Green

Duffy

Janz

et al. 2016

Arch Environ Contam Toxicol

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Mercury (Hg) contamination can pose risks to human and animal health as well as commercial fisheries. Reservoir construction in riverine systems produces flooded conditions amenable to Hg(II)-methylating bacteria, which can transform this relatively benign environmental contaminant into the bioaccumulative, environmentally relevant, and neurotoxic methyl-Hg (MeHg). Hg concentrations ([Hg]) in fishes from reservoirs can take decades to decrease to pre-dam levels, but less is known about Hg exported downstream and its dynamics within downstream fish populations. We examined and compared the multidecadal rates of biotic [Hg] decrease and contemporary factors affecting [Hg] in fish collected from a hydroelectric reservoir (Tobin Lake) and a related downstream fishery (Cumberland Lake) along the Saskatchewan River, Canada. Rates of [Hg] decrease were considered in four species-northern pike (Esox lucius), sauger (Sander canadensis), goldeye (Hiodon alosoides), and walleye (S. vitreus)-all of which showed a significant decrease over time (p < 0.001) and are now lower than Health Canada consumption guidelines (0.5 μg/g). Rates of decrease ranged from 0.5 to 3.9 %/year and were similar between sites in the cases of northern pike and sauger. Contemporary factors affecting [Hg] in walleye collected downstream include fish length (p < 0.001), fish age (p < 0.001), and trophic magnification through the food web (p < 0.001), and relationships between [Hg] and trophic level in predatory and prey fish are now similar to those found in non-Hg-inundated systems at a similar latitude. Together, these results suggest connected contamination between the two sites and delineate the timeline during which [Hg] in a variety of fish species decreased to nontoxic levels in both locations.

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Seasonal and annual trends in forage fish mercury concentrations, San Francisco Bay

Cited by 20 publications

References 49 publications

Spatial and seasonal variations of methylmercury in European glass eels (Anguilla anguilla) in the Adour estuary (France) and relation to their migratory behaviour

Spatial and seasonal variations of methylmercury in European glass eels (Anguilla anguilla) in the Adour estuary (France) and relation to their migratory behaviour

Predictors of mercury spatial patterns in San Francisco Bay forage fish

Historical and Contemporary Patterns of Mercury in a Hydroelectric Reservoir and Downstream Fishery: Concentration Decline in Water and Fishes

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