Review on Birds

In this study heavy metal accumulation examined in avian species using invasive (organs) and non-invasive (feathers) approach. Heavy metals enter ecosystems through natural processes like weathering and anthropogenic sources such as industrial emissions, waste disposal and agricultural practices. The aim of the study is to compare the patterns of heavy metal accumulation among various species. Birds absorb these metals via ingestion, inhalation and direct contact resulting in bioaccumulation and bio magnification across trophic levels. As birds are terrestrial bio indicator of environmental pollution.Feather analysis of birds reflects both internal and external means of exposure, while organ analysis provides insights into tissue-specific accumulation with the liver, gizzard and kidneys typically showing the highest concentrations. Highest and lowest mean±SD values of heavy metals in different types of bird species analyzed and compared across the world. Exposure to heavy metals on birds causes oxidative stress, DNA damage, reproductive impairments and behavioral disruptions in birds. Accumulation patterns vary by species, habitat and trophic level with aquatic and predatory bird.