# Environmental Quality Assessment Using Fecal Metabolomics in Waterfowl from Protected Wetlands in Southwest Spain

## TL;DR

This study uses fecal metabolomics in waterfowl to assess environmental quality in protected wetlands in Spain, revealing pollution-related physiological changes.

## Contribution

The study introduces fecal metabolomics as a noninvasive method to evaluate environmental stress in wetland ecosystems using waterfowl.

## Key findings

- Key metabolites like fatty acids and steroids showed significant alterations linked to diet and pollution.
- Multivariate analyses revealed clear differences between species and wetland sites.
- Altered metabolic pathways included fatty acid, bile acid, and sphingolipid metabolism.

## Abstract

The study of environmental stress requires an understanding
of
biological responses to pollutants, which can be difficult to interpret
due to multiple influencing factors. This study investigates the fecal
metabolome of waterfowl as bioindicators of environmental quality
in two protected wetlands in southwestern Spain: the Odiel Marshes
Biosphere Reserve (OMBR) and the Cádiz Bay Important Bird Area
(CBIBA). Using untargeted UHPLC-QTOF-MS metabolomics, fecal samples
were analyzed from five species: spoonbills, black-headed gulls, yellow-legged
gulls, lesser black-backed gulls, and storks. Significant alterations
were observed in key metabolites, including fatty acids, steroids,
glycerophospholipids, and sphingolipids, reflecting differences in
diet, habitat use, and pollutant exposure. In spoonbills, steroids
and fatty acids represented the largest fractions of the detected
metabolites, while comparisons between gull species revealed variations
in fatty acid and glycerophospholipid levels. Multivariate analyses
showed a clear separation between species and sites. Pathway analysis
identified several altered metabolic routes, primarily involving fatty
acid, bile acid, and sphingolipid metabolism. Overall, these results
demonstrate that fecal metabolomics is a robust noninvasive tool for
assessing pollution-related physiological changes, confirming waterbirds
as effective bioindicators of wetland ecosystem health.