Restoration Research Projects

Researchers are investigating whether adding organic matter as fertilizer can help speed the process of full habitat restoration. They are also comparing the feeding habits of marine organisms in natural and restored marshes in Mission Bay, CA.

Developing the most effective methods of habitat restoration is an ongoing process. The researchers are comparing the feeding habits of marine organisms in natural and restored marshes in Mission Bay, CA, with those in a nearby restored marsh to determine whether the revegetated marsh supports a macrofaunal community (snails, crabs and shellfish) similar to that found in a nearby natural marsh (Levin et al. 1999). Furthermore, they are investigating whether adding organic matter such as alfalfa, peat, kelp or sewage as fertilizer can help speed the process of full habitat restoration in the revegetated marsh. Preliminary findings have suggested that additional organic matter appears to "jumpstart" the marsh's food chain. Sewage encourages greater microalgal growth, which in turn attracts gastropods, amphipods and copepods. These organisms are fed upon by small fish, which are consumed, in turn, by even larger predators.

This study has demonstrated both spatial and temporal variation in carbon, nitrogen and sulfer stable isotopes of primary producers, invertebrates and fishes in created and natural reference marshes. Vascular plants appeared to provide little nutrition to created marsh fauna and blue-green algae appeared important food resources for insects and annelids. Fauna inhabiting creek beds fed on different food resources relative to those inhabiting the marsh surface. Although benthic microalgal biomass and infaunal biomass became similar between created and natural marshes within three years, food webs remained distinct suggesting dissimilar functions within the two marsh types. These findings are expected to help ensure the successful implementation of future restoration projects (NOAA 2000).