The increase of plastic pollution represents a significant ecological threat, particularly in human-impacted environments. However, the effects of plastic ingestion by urban wildlife are less understood. This study investigates the presence of microplastic (MPs; plastic <5 mm in size) and macroplastics (MaPs, plastic >5 mm in size) in yellow-legged gull (Larus michahellis) chicks inhabiting the urban marine ecosystem of Barcelona (northeastern Spain). The stomach contents of 56 gull chicks were analysed, revealing the presence of MPs in 100 % of the individuals and MaPs in 19.64 % of individuals. Additionally, trophic analysis, through stomach content and stable isotope determination, identified links between diet and plastic ingestion, with diet diversity associated with higher MaP abundance. These results highlight the high presence of plastics in the early stages of an urban-dwelling wildlife species and open the potential role of the use of urban gull chicks as sentinels of marine and terrestrial pollution in urban coastal areas. The findings suggest that chicks can serve as bioindicators of plastic pollution, emphasizing the urgent need to address the high levels of plastic contamination in urban environments.

中文翻译：

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城市鸥雏鸟摄入塑料的特征及其对沿海城市用作污染哨兵的影响


塑料污染的增加构成了重大的生态威胁，尤其是在受人类影响的环境中。然而，城市野生动物摄入塑料的影响尚不清楚。本研究调查了栖息在巴塞罗那（西班牙东北部）城市海洋生态系统中的黄腿鸥 （Larus michahellis） 雏鸟中存在的微塑料（MPs;塑料 <5 毫米大小）和大塑料（MaPs，塑料 >5 毫米）。分析了 56 只海鸥雏鸡的胃内容物，显示 100% 的个体存在 MP，19.64% 的个体存在 MaP。此外，通过胃内容物和稳定同位素测定进行营养分析，确定了饮食与塑料摄入之间的联系，饮食多样性与较高的 MaP 丰度相关。这些结果突出了塑料在城市居住野生动物物种早期阶段的大量存在，并揭示了使用城市海鸥雏鸟作为城市沿海地区海洋和陆地污染哨兵的潜在作用。研究结果表明，雏鸡可以作为塑料污染的生物指标，强调迫切需要解决城市环境中高水平的塑料污染问题。