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Katherine C. Marois

Publications and source records attributed to Katherine C. Marois.

5 recordsLinked to original sources
USGS2002

Sublethal effects in avocet and stilt hatchlings from selenium-contaminated sites

Excess selenium (Se) in the aquatic food chain is embryotoxic and teratogenic to avocets, stilts, and other waterbirds. American avocet ( Recurvirostra americana ) and black-necked stilt ( Himantopus mexicanus ) eggs were collected from three sites in the Tulare Lake Basin of California, USA, and hatched in the laboratory. These sites included the Tulare Lake Drainage District-north (TLDD-N, water 2.5 ppb Se), TLDD-south (TLDD-S, water 8.6 ppb Se), and Westfarmers (WF, water 190 ppb Se). Highest egg Se concentrations occurred at WF (geometric mean 31.4 ppm dry wt for avocets and 20.5 ppm dry wt for stilts). Mean egg Se concentrations were 6.7 ppm for avocets and 8.4 ppm for stilts at TLDD-S, and 3.3 ppm for avocets and 2.3 ppm for stilts at TLDD-N. Hatching success and incidence of malformations did not differ among sites, but yolk sac-free hatching weights and bone lengths were less for avocets at the WF site, whereas liver weights and liver to body weight ratios were greater at that site. With increasing Se concentration, oxidative stress was most apparent in avocet hatchlings from WF: hepatic glutathione (GSH) peroxidase activity increased, glucose-6-phosphate dehydrogenase activity decreased, and oxidized glutathione (GSSG) concentration as well as the ratio of GSSG to reduced GSH concentration increased. In stilts, hepatic GSH concentration was lower in WF hatchlings. In conclusion, our findings of Se-impaired embryo growth and hepatotoxicity in avocet hatchlings suggest that oxidative stress observed in hatchlings may be related to these biological effects and may serve as a potential bioindicator of subsequent impaired functions.

California↗
USGS1991

Trace elements and organochlorines in surf scoters from San Francisco Bay, 1985

Surf scoters ( Melanitta perspicillata ) were collected from 6 locations in San Francisco Bay during January and March 1985. Overall, mean concentrations of cadmium and zinc were higher in livers of scoters from the southern region of the Bay, whereas mean iron and lead were higher in those from the northern Bay region. Mean concentrations of arsenic, copper, lead, zinc, aluminum (January only) and iron (January) also differed among individual locations. Mean concentrations of copper and zinc increased, arsenic decreased, and cadmium remained the same between January and March. Selenium and mercury concentrations in scoter livers were not significantly correlated ( P >0.05), but cadmium concentrations in livers and kidneys were positively correlated ( P <0.0001), and body weight was negatively related to mercury concentration in the liver ( P <0.05). Body weight differed among locations but not between January and March. Body weight was correlated with lipid content ( P <0.0001). DDE and PCBs were each detected in 34 of 36 scoter carcasses. DDE increased significantly between January and March at Richmond Harbor, but BCBs did not differ between January and March at the 3 locations that could be tested.

Environmental Monitoring and Assessment↗
USGS1990

Organochlorines and selenium in California night-heron and egret eggs

Exceptionally high concentrations of DDE were found in black-crowned night-heron ( Nycticorax nycticorax ) (geometric mean 8.62 μg g −1 wet wt.) and great egret ( Casmerodius albus ) (24.0 μg g −1 ) eggs collected from the Imperial Valley (Salton Sea), California in 1985. DDE concentrations in 14 of the 87 (16%) randomly selected night-heron eggs from six colonies (two in San Francisco Bay, three in the San Joaquin Valley, and one at Salton Sea) were higher than those associated with reduced reproductive success of night-herons (8 μg g −1 ). In addition, mean shell thickness of night-heron eggs collected from the San Joaquin Valley and from San Francisco Bay during 1982–1984 was significantly less than pre-DDT thickness and was negatively correlated ( r =−0.50, n =75, P <0.0001) with DDE concentration. Mean selenium concentration in night-heron eggs from Salton Sea (1.10 μg g −1 ) was significantly higher than in eggs from three locations in the San Joaquin Valley, and in egret eggs from Salton Sea.

Environmental Monitoring and Assessment↗
USGS1990

Bioaccumulation of selenium in birds at Kesterson Reservoir, California

This study was conducted to determine selenium (Se) concentrations in tissues of birds collected during the 1983-1985 nesting seasons at Kesterson Reservoir (an area receiving high-Se irrigation drainage water), compare them with birds from reference sites within California's Central Valley, and relate them to food-chain Se concentrations at the study sites. Within years, Se in livers of adult birds collected early and late in the nesting season changed significantly at both Kesterson and the primary reference site (Volta Wildlife Area). These changes were related to the length of time birds had been present at the study sites and the associated accumulation (at Kesterson) or depuration (at Volta) of Se. All species showed significant location differences, which were greatest in species that occurred at Kesterson throughout the year or fed more consistently within the reservoir. There were few species differences in Se for birds at the reference sites (where food-chain Se levels were 'normal' [ < 2?g/g, dry wt]). At Kesterson (where bird foods generally contained >50 ?/g Se/g), species patterns varied by year, probably because of varying periods of residence and other factors. Se concentrations in kidneys and livers of American coots (Fulica americana) were significantly correlated (r = 0.9845); Se concentrations in breast muscles and livers of juvenile ducks (Anas spp.) also were correlated (r = 0.8280). Body weights of adult coots were negatively correlated with liver Se concentration. Late-season resident breeding birds or pre-fledging juvenile birds reared at a site usually provided the best indication of site-specific Se bioaccumulation.

California↗