Abstract:
Seabirds accumulate mercury (Hg) due to their long-life span together with their high trophic position. A Hg monitoring in Venice\'s Lagoon using three seabird species occupying different trophic habitat (Thalasseus sandvicensis, Ichthyaetus melanocephalus, and Chroicocephalus ridibundus) confirmed that fledgelings might effectively be used as sentinels of Hg bioavailability. The significant differences in Hg residues in feathers observed among the species highlighted a possible differential exposure due to different diets, with C. ridibundus accumulating more Hg than the other species. Average residues in feathers were not above the threshold associated with adverse effects on birds (5 mg kg- 1). Nevertheless, a large part of the C. ridibundus individuals (58%) exceeded the adverse effect level, underlining the need for strengthening Hg monitoring. Seabirds indeed may provide relevant insight on Hg transfer in food webs and a better picture of the hazards to men when bird species forage on species exploited for human consumption.
摘要:
海鸟由于其长寿命和高营养位置而积聚汞(Hg)。使用占据不同营养栖息地的三种海鸟物种(Thalasseussandvicensis,黑头鱼,和Chroicocephalusridibundus)证实,雏鸟可能有效地用作汞生物利用度的哨兵。物种之间观察到的羽毛中汞残留的显着差异突出表明,由于不同的饮食,可能存在差异暴露,C.ridibundus积累的汞比其他物种多。羽毛中的平均残留物不超过与对鸟类的不利影响相关的阈值(5mgkg-1)。然而,大部分C.ridibundus个体(58%)超过了不良反应水平,强调需要加强汞监测。海鸟确实可以提供有关食物网中汞转移的相关见解,并更好地了解当鸟类觅食供人类食用的物种时对人类的危害。