Food Web Fuel Differs Across Habitats and Seasons of a Tidal Freshwater Estuary

• DOI: 10.1007/s12237-020-00762-9
• Publication Date: 2020-07-12T06:02:57Z
• Authors: Matthew Young; Emily Howe; Teejay O’Rear; Kathleen Berridge; Peter Moyle
• Keywords: Primary producers

Abstract Estuarine food webs are fueled by multiple different primary producers. However, identifying the relative importance of each producer to consumers is difficult, particularly for fishes that utilize sources due both their mobility and generally high trophic levels. Previous studies have documented broad spatial differences in producers within Upper San Francisco Estuary, California, including separation between pelagic littoral webs. In this study, we evaluated adult three closely spaced subregions represented disparate habitat types (a tidal wetland channel, a turbid backwater deep open-water channel), potential outcome local restoration projects. Using stable isotope analysis coupled with Bayesian mixing model, identified significant primary-producer contribution invertebrates across habitats seasons, especially submersed aquatic vegetation phytoplankton. Most utilized showed little segregation among habitats. Availability differs seasonally scales, helping buffer environmental variability thus enhancing web resilience. Ecosystem may improve emphasis on restoring wide variety support consumers.