Geographic Variation in Salt Marsh Structure and Function for Nekton: a Guide to Finding Commonality Across Multiple Scales

Abstract

Coastal salt marshes are distributed widely across the globe and are considered essential habitat for many fish and crustacean species. Yet the literature on fishery support by salt marshes has largely been based on a few geographically distinct model systems, and as a result, inadequately captures the hierarchical nature of salt marsh pattern, process, and variation across space and time. A better understanding of geographic variation and drivers of commonalities and differences across salt marsh systems is essential to informing future management practices.Here, we address the key drivers of geographic variation in salt marshes: hydroperiod, seascape configuration, geomorphology, climatic region, sediment supply and riverine input, salinity, vegetation composition, and human activities. Future efforts to manage, conserve, and restore these habitats will require consideration of how environmental drivers within marshes affect the overall structure and subsequent function for fisheries species. We propose a future research agenda that provides both the consistent collection and reporting of sources of variation in smallscale studies and collaborative networks running parallel studies across large scales and geographically distinct locations to provide analogous information for data poor locations. These comparisons are needed to identify and prioritize restoration or conservation efforts, identify sources of variation among regions, and best manage fisheries and food resources across the globe.

Using successional drivers to understand spatiotemporal dynamics in intertidal mudflat communities

“…They also observed seasonal variation in successional dynamics influenced by the various natural processes listed above, and so had difficulty defining a single successional model that could describe observed dynamics regardless of season. Our study adds its voice to the call (e.g., Ziegler et al, 2021) for more research that specifically builds into field experimental designs evaluation of temporal and spatial variation, such as start times and geographic locations, since such variation may or may not significantly impact the outcome.…”

“…The influence of successional drivers can be affected by seasonal and weather differences (Pacheco et al, 2010), species reproductive cycles (Antoniadou et al, 2011), and migratory behavior (Boudreau & Hamilton, 2012). In addition, particular ecosystems may vary depending on differences in climate (Ziegler et al, 2021), hydroperiod (Baker et al, 2015), and site history (Matthews & Endress, 2010). Logistical constraints have often restricted researchers to conducting field experiments at a single time of year, in one location, and focusing on individual drivers (Meiners et al, 2015).…”

Estimating and Applying Fish and Invertebrate Density and Production Enhancement from Seagrass, Salt Marsh Edge, and Oyster Reef Nursery Habitats in the Gulf of Mexico

“…We illustrate how these estimates can be applied to individual locations to better understand the contribution of existing habitat and the potential fish and invertebrate production benefits of habitat restoration. In addition, by applying our approach to case study locations in the Gulf of Mexico with bay-specific fish species information, we highlight geographic variation in the functional values of coastal habitats (Ziegler et al 2021). The approach described is easily transferable to other regions where sufficient juvenile fish and invertebrate density data exist across paired unstructured and threatened structured habitats.…”

Complex Tidal Marsh Dynamics Structure Fish Foraging Patterns in the San Francisco Estuary

“…While direct transport may occur during periods of tidal or fluvial exchange (Teal 1962;Nixon 1980;Odum 2000), indirect transport may occur when primary and secondary consumers (fishes and invertebrates) move out of marshes via tidal migration, juvenile recruitment to adult habitats, or consumption by transient predators (in a series of "trophic relays" (Kneib 2000)). Trophic relays have now been examined in numerous systems across the globe (Litvin and Weinstein 2004;Hollingsworth and Connolly 2006;Able et al 2009;Nelson et al 2012;Baker et al 2013;Ziegler et al 2019;Lesser et al 2020;Nemerson and Able 2020), which have revealed substantial geographic variation in tidal marsh structure and function (Ziegler et al 2021).…”