We assessed the levels of Pb, Cd, and Mn in contour feathers of the feral pigeon (Columba livia) and house crow (Corvus splendens) obtained from five urban/suburban locations across Sri Lanka, using the AAS following wet digestion. Our key objectives were to compare accumulation levels in the two avian species with different foraging habits and living in common locations, and to establish baseline information on the presence of these metals in multiple locations in Sri Lanka with varying levels of urbanization. Owing to reservations that have been expressed by previous workers regarding the use of feathers for assessing heavy metal pollution, we first tested the efficacy of contour feathers by using our data for comparing the coefficients of variation in metal levels within and between locations. This showed that in over 95% of the cases, variations within locations were lower than between locations, indicating that freshly shed contour feathers that were used in the present study were reliable indicators of the status of bioaccumulation of the heavy metals in the environment. In interspecific comparisons, other than in the two suburban locations, Pb was present at much higher levels in the house crow than in the feral pigeon, whereas accumulation patterns with respect to Cd and Mn were inconsistent, suggesting that granivores may not, in all situations, accumulate lower levels than scavengers in the same environment. Owing to such interspecific variations in the patterns of accumulation of different heavy metals, the selection of a single species for assessing levels of pollution from heavy metals may not be prudent. Pb and Cd levels in both species were strongly and positively associated with human population density. The levels of Pb and Cd were highest in Colombo (commercial capital). In Colombo and Kalutara, the recorded levels in the house crow exceeded the thresholds that have the potential to inflict adverse impacts on avian species.

我们评估了野鸽（Columba livia）和家鸦（Corvus splendens）的轮廓羽毛中Pb，Cd和Mn的水平）是通过湿法消化后使用原子吸收光谱法从斯里兰卡五个城市/郊区获得的。我们的主要目标是比较两种具有不同觅食习惯和生活在共同地点的鸟类的积累水平，并建立有关这些金属在城市化程度不同的斯里兰卡多个地方存在的基准信息。由于以前的工作人员对使用羽毛评估重金属污染表达了保留意见，因此我们首先通过使用我们的数据来比较轮廓金属在位置之间和位置之间的变化系数，来测试轮廓羽毛的功效。这表明在超过95％的情况下，位置内部的差异小于位置之间的差异，这表明本研究中使用的刚脱落的轮廓羽毛是环境中重金属生物积累状态的可靠指标。在种间比较中，除了在两个郊区以外，家禽中的铅含量都比野生鸽子高，而镉和锰的积累方式却不一致，这表明在所有情况下食肉动物可能并非如此在相同的环境中，其清除水平要比清除剂低。由于不同重金属的积累方式存在种间差异，选择单一物种评估重金属污染水平可能并不明智。两种物种中的铅和镉含量均与人口密度密切相关。铅和镉的含量在可伦坡（商业资本）中最高。在科伦坡和卡卢特勒，家鸦的记录水平超过了可能对禽类造成不利影响的阈值。