US EPA

2481259 

Journal Article 

Does mercury contamination reduce body condition of endangered California clapper rails? 

Ackerman, JT; Overton, CT; Casazza, ML; Takekawa, JY; Eagles-Smith, CA; Keister, RA; Herzog, MP 

2012 

Yes 

Environmental Pollution
ISSN: 0269-7491
EISSN: 1873-6424 

162 

439-448 

English 

22243896 

10.1016/j.envpol.2011.12.004 

WOS:000301087800056 

http://www.sciencedirect.com/science/article/pii/S0269749111006610
Exit
 

We examined mercury exposure in 133 endangered California clapper rails (Rallus longirostris obsoletus) within tidal marsh habitats of San Francisco Bay, California from 2006 to 2010. Mean total mercury concentrations were 0.56 mu g/g ww in blood (range: 0.15-1.43), 9.87 mu g/g fw in head feathers (3.37-22.0), 9.04 mu g/g fw in breast feathers (3.68-20.2), and 0.57 mu g/g fww in abandoned eggs (0.15-2.70). We recaptured 21 clapper rails and most had low within-individual variation in mercury. Differences in mercury concentrations were largely attributed to tidal marsh site, with some evidence for year and quadratic date effects. Mercury concentrations in feathers were correlated with blood, and slopes differed between sexes (R-2 = 0.58-0.76). Body condition was negatively related to mercury concentrations. Model averaged estimates indicated a potential decrease in body mass of 20-22 g (5-7%) over the observed range of mercury concentrations. Our results indicate the potential for detrimental effects of mercury contamination on endangered California clapper rails in tidal marsh habitats. Published by Elsevier Ltd. 

Mercury; Bird; Bioaccumulation; Body condition; San Francisco Bay