Considerations of Habitat Linkages, Estuarine Landscapes, and the Trophic Spectrum in Wetland Restoration Design

• Published in: Journal of coastal research no. 40; pp. 51 - 63
• Main Authors: Weinstein, Michael P., Litvin, Steven Y., Guida, Vincent G.
• Format: Journal Article
• Language: English
• Published: Lawrence, KS Coastal Education & Research Foundation (CERF) 01-12-2005; Coastal Education and Research Foundation
• Subjects: Anchovies; Animal, plant and microbial ecology; Applied ecology; Aquatic habitats; Biological and medical sciences; Conservation, protection and management of environment and wildlife; Creeks; Environmental degradation: ecosystems survey and restoration; Estuaries; Food webs; Fundamental and applied biological sciences. Psychology; Isotopes; Marine ecology; Marshes; Salt marshes; Wetland ecology; Brackish water environment; Landscape; Estuaries; wetland restorationdesign; Feeding; Freshwater environment; Aquatic environment; Estuarine landscapes; trophic spectrum; Diet; Habitat; Ecological recovery; Wetland
• ISSN: 0749-0208; 1551-5036

Wetland restoration designs do not frequently consider functional linkages among habitats in the estuarine landscape, nor do they focus sufficient attention on the role of marsh morphology in promoting the efficient exchange of materials and organisms between the intertidal and subtidal water column. These features should be considered, because many marine organisms may benefit from trophic subsidies from adjacent habitats without ever entering them. Stable isotopes were used to examine trophic linkages between primary producers and marine finfishes to highlight the importance of individual life history traits and to punctuate the argument for promoting habitat connectivity (exchange of materials and organisms) in restoration planning. We demonstrate that the trophic spectrum of an estuarine resident, the Morone americana (white perch), and two marine transients, Anchoa mitchilli (bay anchovy) and Cynoscion regalis (weakfish), are largely functions of locally available organic matter distributed along a gradient of estuarine resources. In both salt marshes and open waters, there was a transition in whole-body isotopic composition in all three species associated with the estuary-wide gradient in nutrient availability ranging from macrophytes and benthic microalgae in marshes, to phytoplankton (as suspended particulate matter) in the open estuary. As anticipated, phytoplankton contributed more to bay anchovy and weakfish biomass, especially in open waters, than to white perch. Our results also suggest that marine transients benefit from the presence of salt marshes without necessarily occupying them. Thus the estuarine "commissary" serves up different recipes in different regions, and the many estuarine-dependent species apparently take full advantage of these varied sources of primary production at the base of the food web when seeking energy for rapid growth and survival.