Habitat restoration is commonly used to recover ecosystem services, but due to resource constraints, post-project monitoring often fails to fully evaluate the recovery of important ecosystem functions. Metric-based indicators use simple-to-measure variables to assess ecosystem health and function, thereby providing a time- and cost-effective method to improve monitoring. We used a tidal marsh dataset to develop metric-based indicators of ecosystem recovery. In 2021 and 2022, we surveyed eight restored/created and three natural reference tidal marshes in the northern Gulf of Mexico to assess recovery of ecosystem attributes [e.g., above- and below-ground biomass, soil organic matter (SOM), and sediment total carbon (C) and total nitrogen (N)]. To determine what combinations of variables best predicted recovery, we split our data into model training and testing datasets, used backward model selection, and then created and tested a metric-based indicator of ecosystem recovery. Recovery of plant above- and below-ground biomass and sediment structure (i.e., SOM, C, and N)—important measures of wetland carbon sink capacity and biogeochemical functioning—could be predicted through a combination of simpler-to-measure variables, such as time since restoration, percent plant cover, and sediment bulk density. The indicator constructed from these relationships was highly effective in predicting the development of ecosystem attributes (r = 0.85, p < 0.001). This indicator approach provides an effective but simple method to assess the recovery of ecosystem attributes in tidal marshes, and it can be used to develop similar indicators in other ecosystems. By overcoming resource constraints of post-project monitoring, metric-based indicators of ecosystem recovery may serve as a key strategy to improve restoration outcomes.

A significant amount of tidal marsh restoration has occurred over the past two decades. However, restored marshes often fail to recover biological structure and ecosystem functions comparable to reference marshes. We implemented a 13-site inventory to evaluate the recovery of zooplankton and meroplankton abundance and community composition along the Mississippi and Alabama Gulf coasts. Understanding the recovery of zooplankton and meroplankton communities in restored marshes is critical, as many planktonic invertebrate species contribute to nutrient cycling and food web dynamics. We found that zooplankton and meroplankton communities in restored tidal marshes were comparable in total abundance, taxonomic richness, and taxonomic composition to communities observed in reference tidal marshes — with composition being driven mainly by surface water salinity. But zooplankton and meroplankton communities in restored marshes did have lower evenness and diversity than comparable reference marshes. These results suggest that zooplankton and meroplankton communities in restored marshes along the Mississippi and Alabama Gulf coast tend to recover after 7–34 years and support robust populations of prey items for larger, ecologically and economically-important species (e.g., fishes).