Campbell Abigail, Perold Vonica, Ryan Peter G
FitzPatrick Institute of African Ornithology, University of Cape Town, Rondebosch 7701, South Africa.
FitzPatrick Institute of African Ornithology, University of Cape Town, Rondebosch 7701, South Africa.
Mar Pollut Bull. 2025 Jun;215:117904. doi: 10.1016/j.marpolbul.2025.117904. Epub 2025 Apr 5.
Plastic floating at sea is difficult to measure due to its high spatial and temporal variation. White-chinned Petrels Procellaria aequinoctialis are surface-foraging seabirds found in the Southern Ocean that often ingest plastic. They are susceptible to being caught accidentally on long-line fishing gear, providing carcasses that can be used to monitor changes in the incidence and characteristics of plastic floating at sea. Of the 2486 White-chinned Petrels sampled off South Africa between 1979 and 2024, 57 % contained plastic. Data were grouped into time periods to determine temporal variation while accounting for unequal yearly sample sizes. The proportion of birds containing plastic has not changed since 1979. The number of plastic items ingested increased from an average of 2 items per bird in the early 1980s to 7 in 2017-24, mainly due to an increase in the last 5 years, but there has been no change in the total mass of ingested plastic. The proportion of pellets declined from 25 % to 17 %, with the average number of pellets per bird following a similar trend until two highly impacted birds were found in 2022 and 2023, possibly reflecting recent large pellet spills at sea off South Africa. White-chinned Petrels ingest more flexible plastics (threads and films) than other petrels, potentially linked to their behaviour of scavenging behind ships. Some birds contained fibrous gastroliths, up to 20 mm in diameter. Recording plastic loads in White-chinned Petrels offers a useful method to monitor long-term changes in floating plastic at sea.
由于海上漂浮塑料具有高度的时空变异性，因此很难对其进行测量。白额圆尾鹱是在南大洋发现的在海面觅食的海鸟，经常摄入塑料。它们很容易意外地被延绳钓渔具缠住，从而提供了可以用来监测海上漂浮塑料的发生率和特征变化的尸体。在1979年至2024年间从南非附近海域采样的2486只白额圆尾鹱中，57%体内含有塑料。数据按时间段分组，以确定时间变化，同时考虑到每年样本量不等的情况。自1979年以来，体内含有塑料的鸟类比例没有变化。摄入的塑料物品数量从20世纪80年代初每只鸟平均2件增加到2017 - 2024年的7件，这主要是由于过去5年的增加，但摄入塑料的总质量没有变化。丸粒的比例从25%下降到17%，每只鸟摄入丸粒的平均数量也呈现类似趋势，直到2022年和2023年发现了两只受影响严重的鸟，这可能反映了南非附近海域近期发生的大型丸粒泄漏事件。白额圆尾鹱比其他圆尾鹱摄入更多的柔性塑料（线和薄膜），这可能与其在船后觅食的行为有关。一些鸟体内含有直径达20毫米的纤维状胃石。记录白额圆尾鹱体内的塑料负荷为监测海上漂浮塑料的长期变化提供了一种有用的方法。
