Department of Biosciences, University of Oslo, Oslo, Norway.
Section for Marine Pollution, Norwegian Institute for Water Research, Oslo, Norway.
Integr Environ Assess Manag. 2021 Mar;17(2):422-433. doi: 10.1002/ieam.4340. Epub 2020 Oct 8.
Seabirds like gulls are common indicators in contaminant monitoring. The herring gull (Larus argentatus) is a generalist with a broad range of dietary sources, possibly introducing a weakness in its representativeness of aquatic contamination. To investigate the herring gull as an indicator of contamination in an urban-influenced fjord, the Norwegian Oslofjord, we compared concentrations of a range of lipophilic and protein-associated organohalogen contaminants (OHCs), Hg, and dietary markers in blood (n = 15), and eggs (n = 15) between the herring gull and the strict marine-feeding common eider (Somateria mollissima) in the breeding period of May 2017. Dietary markers showed that the herring gull was less representative of the marine food web than the common eider. We found higher concentrations of lipophilic OHCs (wet weight and lipid weight) and Hg (dry weight) in the blood of common eider (mean ± SE ∑PCB = 210 ± 126 ng/g ww, 60 600 ± 28 300 ng/g lw; mean Hg = 4.94 ± 0.438 ng/g dw) than of the herring gull (mean ± SE ∑PCB = 19.0 ± 15.6 ng/g ww, 1210 ± 1510 ng/g lw; mean Hg = 4.26 ± 0.438 ng/g dw). Eggs gave opposite results; higher wet weight and lipid weight OHC concentrations in the herring gull (mean ± SE ∑PCB = 257 ± 203 ng/g ww, 3240 ± 2610 ng/g lw) than the common eider (mean ± SE ∑PCB = 18.2 ± 20.8 ng/g ww, 101 ± 121 ng/g lw), resulting in higher OHC maternal transfer ratios in gulls than eiders. We suggest that the matrix differences are due to fasting during incubation in the common eider. We suggest that in urban areas, herring gull might not be representative as an indicator of marine contamination but rather urban contaminant exposure. The common eider is a better indicator of marine pollution in the Oslofjord. The results are influenced by the matrix choice, as breeding strategy affects lipid dynamics regarding the transfer of lipids and contaminants to eggs and remobilization of contaminants from lipids to blood during incubation, when blood is drawn from the mother. Our results illustrate the benefit of a multispecies approach for a thorough picture of contaminant status in urban marine ecosystems. Integr Environ Assess Manag 2021;17:422-433. © 2020 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).
海鸥等海鸟是污染物监测中的常见指示物。银鸥（Larus argentatus）是一种杂食性动物，其食物来源广泛，这可能使其在代表水生污染方面存在弱点。为了研究海鸥作为受城市影响的峡湾——挪威奥斯陆峡湾污染指示物的作用，我们比较了繁殖期（2017 年 5 月）海鸥和严格的海洋食性普通绒鸭（Somateria mollissima）血液（n=15）和卵（n=15）中一系列亲脂性和与蛋白质结合的有机卤代污染物（OHC）、汞和膳食标志物的浓度。膳食标志物表明，海鸥在海洋食物网中的代表性不如普通绒鸭。我们发现，普通绒鸭血液中的亲脂性 OHC（湿重和脂重）和汞（干重）浓度高于海鸥（∑PCB 湿重平均值±标准误=210±126ng/g ww，60600±28300ng/g lw；Hg 平均值±标准误=4.94±0.438ng/g dw）（∑PCB 干重平均值±标准误=19.0±15.6ng/g ww，1210±1510ng/g lw；Hg 平均值±标准误=4.26±0.438ng/g dw）。卵的结果则相反；海鸥卵中的亲脂性 OHC（∑PCB 湿重平均值±标准误=257±203ng/g ww，3240±2610ng/g lw）比普通绒鸭（∑PCB 湿重平均值±标准误=18.2±20.8ng/g ww，101±121ng/g lw）高，这导致了海鸥体内 OHC 的母体转移率高于普通绒鸭。我们认为，基质差异是由于普通绒鸭在孵化期间禁食造成的。我们认为，在城市地区，海鸥可能不是海洋污染的代表性指示物，而是城市污染物暴露的指示物。普通绒鸭是奥斯陆峡湾海洋污染的更好指示物。结果受到基质选择的影响，因为繁殖策略会影响脂质动力学，从而影响到脂质和污染物向卵的转移，以及在孵化期间从脂质向血液中重新动员污染物，此时从母体抽取血液。我们的研究结果说明了采用多物种方法的好处，它可以全面了解城市海洋生态系统中的污染物状况。《综合环境评估与管理》2021 年；17：422-433。©2020 作者。综合环境评估与管理由 Wiley 期刊 LLC 代表环境毒理与化学学会（SETAC）出版。
