Charles Darwin Foundation, Charles Darwin Avenue, Santa Cruz, 200350, Galapagos Islands, Ecuador; Museo de Zoología, Escuela de Biología, Facultad de Ciencias Exactas y Naturales, Pontificia Universidad Católica del Ecuador, Quito, Ecuador.
Museo de Zoología, Escuela de Biología, Facultad de Ciencias Exactas y Naturales, Pontificia Universidad Católica del Ecuador, Quito, Ecuador.
Environ Pollut. 2024 Jan 1;340(Pt 2):122780. doi: 10.1016/j.envpol.2023.122780. Epub 2023 Oct 18.
The human population of Galapagos has rapidly increased in the last decades accelerating the anthropogenic pressures on the archipelago's natural resources. The growing human footprint, including inadequate management of garbage, may lead to conservation conflicts. Here, we assessed the ingestion of debris by Western Santa Cruz giant tortoises (Chelonoidis porteri) within human-modified and protected areas. Additionally, we characterized environmental debris and quantified tortoise abundance together with tortoise fecal samples. We processed a total of 6629 fecal samples along a gradient of anthropogenic disturbance based on human debris presence. We found 590 pieces of debris in samples within human-modified areas (mean of 3.97 items/kg of feces) and only two pieces in the protected area (mean of 0.08 items/kg of feces). Plastic waste was the predominant category in feces within the anthropic area (86.3%; n = 511), followed by cloth, metal, paper, synthetic rubber, construction materials, and glass. On average, the proportion of plastic was higher in feces (84%) than it was in environmental debris (67%), denoting that plastics are more readily ingested than other types of debris. We also found that green, white, and light blue plastics were consumed more often than their prevalence in the environment, suggesting color discrimination. Tortoise abundance was higher in the protected area when compared to the human-modified area; however, recapture rates were higher in anthropized landscapes which increases tortoise exposure to plastics and other human associated threats. Our results indicate that plastics are frequently consumed by tortoises in the polluted anthropic areas of western Santa Cruz, but scarce in protected areas. More research is needed to understand the negative impacts associated with plastics for Galapagos terrestrial species. We encourage local stakeholders to implement current policies limiting expansion of urban areas, plastic use, and improving waste management systems to minimize threats to human and animal health.
在过去几十年中，加拉帕戈斯群岛的人口迅速增长，加速了人类对该群岛自然资源的压力。人类足迹的不断扩大，包括垃圾管理不善，可能导致保护冲突。在这里，我们评估了西部圣克鲁斯巨龟（Chelonoidis porteri）摄入碎片的情况，这些碎片来自人类改造和受保护的区域。此外，我们还对环境碎片进行了特征描述，并对巨龟的数量以及巨龟粪便样本进行了量化。我们沿着人为干扰梯度，共处理了 6629 份粪便样本，这些样本来自人类改造区和受保护区。我们在人类改造区的样本中发现了 590 块碎片（粪便平均每公斤 3.97 件），而在受保护区只发现了两块（粪便平均每公斤 0.08 件）。在人为区域的粪便中，塑料垃圾是主要类别（86.3%；n=511），其次是布、金属、纸、合成橡胶、建筑材料和玻璃。平均而言，粪便中塑料的比例（84%）高于环境碎片中的比例（67%），这表明塑料比其他类型的碎片更容易被摄入。我们还发现，绿色、白色和浅蓝色的塑料比它们在环境中的比例更常被消耗，这表明龟类有颜色识别能力。与人类改造区相比，受保护区的巨龟数量更高；然而，在人为景观中，巨龟的再捕获率更高，这增加了它们接触塑料和其他与人类相关威胁的机会。我们的研究结果表明，在西部圣克鲁斯受污染的人类改造区，巨龟经常摄入塑料，但在受保护的地区却很少。需要更多的研究来了解塑料对加拉帕戈斯陆地物种的负面影响。我们鼓励当地利益相关者实施限制城市地区扩张、限制塑料使用和改善废物管理系统的现行政策，以尽量减少对人类和动物健康的威胁。
