Efficient fuelling is essential for migratory birds because fuel loads and fuelling rates affect individual fitness and survival during migration. Many migrant shorebirds are exposed to oil pollution and its toxic constituents, polycyclic aromatic hydrocarbons (PAHs), at migratory staging sites, which has the potential to interfere with avian refuelling physiology. In this study, we orally dosed shorebirds with environmentally-relevant PAH mixtures to simulate dietary exposure during staging. Forty-nine wild-caught Sanderling (Calidris alba) were exposed to 0 (control), 12.6 (low), 126 (medium), or 1260 (high) μg total PAH/kg body weight/day. Birds were dosed during a 21-day period of autumn pre-migratory fuelling to mimic the typical staging duration of Sanderling. We measured daily changes in mass and fat loads, as well as ethoxyresorufin-O-deethylase (EROD) activity, serum biochemical profiles, and liver mass and lipid content following dosing. All dose groups gained fat and increased in mass (size-corrected) during the study period, with females having a higher average body mass than males. However, mass gain was 3.9, 5.4, and 3.8 times lower in the low, medium, and high dose groups, respectively, relative to controls, and body mass in the medium and high dose groups significantly declined near the end of the experiment. EROD activity showed a dose-dependent increase and was significantly elevated in the high dose group relative to controls. Higher individual EROD activity was associated with reduced serum bile acid and elevated serum creatine kinase concentrations in both sexes, and with elevated serum lipase concentrations in females. These results suggest that PAH exposure in Sanderling can interfere with mechanisms of lipid transport and metabolism, can cause muscle damage, and can lead to reduced overall fat loads that are critical to staging duration, departure decisions, migratory speed, and flight range. Given that many shorebirds migrate thousands of kilometers between the breeding and wintering grounds and frequently aggregate at key staging sites that are subject to contamination, PAH exposure likely represents a significant threat to shorebird migratory success.

有效的加油对于候鸟来说是必不可少的，因为加油量和加油速率会影响候鸟的个体健康和生存。许多迁徙shore鸟在候鸟迁徙地点暴露于石油污染及其有毒成分多环芳烃（PAHs）中，有可能干扰鸟类的加油生理。在这项研究中，我们给水鸟口服与环境相关的PAH混合物，以模拟分期期间的饮食暴露。四十九野外捕猎的桑德林（Calidris alba）暴露于0（对照），12.6（低），126（中）或1260（高）μg总PAH / kg体重/天。鸟类在迁徙前的21天秋季加油期间进行剂量给药，以模仿桑德林犬的典型分期持续时间。我们测量了体重和脂肪负荷以及乙氧基间苯二酚-O的每日变化给药后的脱-脱氢酶（EROD）活性，血清生化特征以及肝脏质量和脂质含量。在研究期间，所有剂量组均增加了脂肪并增加了体重（经尺寸校正），女性的平均体重高于男性。但是，相对于对照组，低，中和高剂量组的体重增加分别低3.9、5.4和3.8倍，中，高剂量组的体重在实验快结束时显着下降。EROD活性显示出剂量依赖性的增加，并且相对于对照组在高剂量组中明显升高。男女个体的较高EROD活性与血清胆汁酸减少和血清肌酸激酶浓度升高有关，与女性血清脂肪酶浓度升高有关。这些结果表明，桑德林的PAH暴露会干扰脂质运输和新陈代谢的机制，会导致肌肉损伤，并会导致总体脂肪负荷降低，这对于分期时间，出发决策，迁徙速度和飞行范围至关重要。鉴于许多shore鸟在繁殖场和越冬场之间迁移了数千公里，并且经常聚集在容易受到污染的关键分阶段，因此，PAH暴露可能对bird鸟的迁徙成功构成重大威胁。