Aarif K M, Rubeena K A, Nefla Aymen, Musilova Zuzana, Musil Petr, Bin Muzaffar Sabir
Department of Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences, Kamýcka 129, Praha Suchdol, Prague CZ-165 21, Czech Republic.
Centre for Environment and Marine Studies, Research & Innovation, King Fahd University of Petroleum & Minerals, Dhahran 31251, Saudi Arabia.
Ecotoxicol Environ Saf. 2025 Jan 1;289:117690. doi: 10.1016/j.ecoenv.2025.117690. Epub 2025 Jan 10.
Heavy metal pollution is a growing environmental concern as it causes the degradation of wetlands by affecting the organisms at different trophic levels. Shorebirds typically feed on benthic invertebrates including polychaete worms, crustaceans and molluscs. Thus, the assessment of bioconcentration of heavy metals in shorebirds provides an insight into the extent of bioaccumulation of these hazardous metals in the upper trophic levels. We studied the variation in the bioconcentration of hazardous heavy metals (chromium, lead and cadmium) in the faeces of 12 species of shorebirds (belonging to different foraging guilds including Endangered Great Knot, Vulnerable Grey Plover, Broad billed Sandpiper and Curlew Sandpiper and Near Threatened Eurasian Oystercatcher, Ruddy Turnstone and Dunlin) in relation to trends in their abundance over a period of five years (2019-2023). The study spanned over three different habitats (mudflats, mangroves and sand beaches) of Kadalundi Vallikkunnu Community Reserve (KVCR) and adjoining sand beaches, which are important wintering/ stop-over sites for the migrant shorebirds that provide abundant nutritional resources for the foraging shorebirds. We demonstrate that there has been a drastic increase in the heavy metal concentration in shorebird faeces from 2019 to 2023. Further, the findings indicate that predating and biofilm-grazing shorebirds in mangrove habitats, as well as small-bodied shorebirds in general are exposed to high levels of heavy metals. This study highlights that heavy metals in the coastal habitats are increasing and that there are potential risks from exposure to foraging shorebirds. Heavy metals have known adverse effects on shorebirds. Our study shows that reducing pollution and protecting community reserves alongside their surrounding habitats are crucial to combat biodiversity loss and maintain diversity in these areas.
重金属污染日益引起环境关注，因为它通过影响不同营养级的生物导致湿地退化。滨鸟通常以底栖无脊椎动物为食，包括多毛类蠕虫、甲壳类动物和软体动物。因此，评估滨鸟体内重金属的生物富集情况有助于深入了解这些有害金属在上营养级的生物累积程度。我们研究了12种滨鸟（属于不同觅食类群，包括濒危的大滨鹬、易危的灰斑鸻、阔嘴鹬和弯嘴滨鹬，以及近危的欧亚蛎鹬、赤颈鸻和黑腹滨鹬）粪便中有害重金属（铬、铅和镉）的生物富集变化，以及它们在五年（2019 - 2023年）期间数量的变化趋势。该研究涵盖了卡达伦迪瓦利昆努社区保护区（KVCR）的三个不同栖息地（泥滩、红树林和沙滩）以及毗邻的沙滩，这些地方是候鸟滨鸟重要的越冬/中途停留地，为觅食的滨鸟提供了丰富的营养资源。我们证明，从2019年到2023年，滨鸟粪便中的重金属浓度急剧增加。此外，研究结果表明，红树林栖息地中捕食和刮食生物膜的滨鸟，以及一般体型较小的滨鸟都暴露在高水平的重金属环境中。这项研究强调，沿海栖息地的重金属含量在增加，觅食的滨鸟面临接触重金属的潜在风险。已知重金属对滨鸟有不利影响。我们的研究表明，减少污染并保护社区保护区及其周边栖息地对于应对生物多样性丧失和维持这些地区的多样性至关重要。
