Elucidating Sexual and Spatial Influences on the Trophic Ecology of Amazon River Dolphins (<i>Inia geoffrensis</i>) and Mercury Contamination.

ABSTRACT: The Amazon Basin hosts an immense biodiversity, including the endemic Amazon River dolphin (Inia geoffrensis). Dietary exposure to mercury (Hg) is one of the threats to this top predator species. This study investigated the relationship between Hg exposure, trophic position and foraging areas in I. geoffrensis. We analyzed Hg concentrations and stable carbon (δ¹³C) and nitrogen (δ¹⁵N) isotope ratios in 111 blood samples collected in different years. The Hg concentrations ranged from 23 to 582 μg/kg wet weight, while mean δ¹³C and δ¹⁵N values were -29.6 ± 1.7‰ and 9.8 ± 0.5‰, respectively. Narrower isotopic niche areas were observed in the latest year analyzed, suggesting reduced prey availability and/or restricted foraging areas. Ma

SUBMITTER: Vannuci-Silva M 

PROVIDER: S-EPMC12573784 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature