Arthropod communities in a selenium-contaminated habitat with a focus on ant species

• Published in: Environmental pollution (1987) Vol. 220; no. Pt A; pp. 234 - 241
• Main Authors: De La Riva, Deborah G., Hladun, Kristen R., Vindiola, Beatriz G., Trumble, John T.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-01-2017
• Subjects: Animals; Ants - drug effects; Ants - physiology; Arthropoda; Arthropods - physiology; Bioaccumulation; Disturbance; Ecosystem; Environmental Monitoring; Formicidae; Plants; Pollution; Selenium - toxicity; Soil - chemistry; Soil Pollutants - toxicity; Solenopsis xyloni; Species composition; Trophic groups; USA, California, Kesterson Reservoir; Pollution; Species composition; Trophic groups; Bioaccumulation; Disturbance
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2016.09.052

The selenium contamination event that occurred at Kesterson Reservoir (Merced Co., CA) during the 1970–80s is a frequently cited example for the negative effects of contamination on wildlife. Despite the importance of arthropods for ecosystem services and functioning, relatively little information is available as to the impacts of pollution on arthropod community dynamics. We conducted surveys of the arthropod community present at Kesterson Reservoir to assess the impacts of selenium contamination on arthropod diversity, with a focus on ant species richness, composition and density. Trophic groups were compared to determine which arthropods were potentially receiving the greatest selenium exposure. Plant samples were analyzed to determine the selenium content by site and by location within plant. Soil concentrations varied across the study sites, but not across habitat types. Topsoil contained higher levels of selenium compared to core samples. Plants contained similar concentrations of selenium in their leaves, stems and flowers, but flowers contained the greatest range of concentrations. Individuals within the detritivores/decomposers and predators accumulated the greatest concentrations of selenium, whereas nectarivores contained the lowest concentrations. Species composition differed across the sites: Dorymyrmex bicolor was located only at the site containing the greatest soil selenium concentration, but Solenopsis xyloni was found at most sites and was predominant at six of the sites. Selenium concentrations in ants varied by species and collection sites. Nest density was also found to differ across sites, but was not related to soil selenium or any of the habitat variables measured in our study. Selenium was not found to impact species richness, but was a significant variable for the occurrence of two out of the eight native species identified.
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•Eight native ant species were found residing at Kesterson Reservoir.•Selenium was a significant factor in the presence/absence of two ant species.•Native ant species may be more tolerant than certain invasive ant species.•Bioaccumulation of selenium differed across ant species and trophic groups.•Selenium exposure to pollinating insects may vary across seasons.