Does the common reed, Phragmites australis, affect essential fish habitat?

Since the early 1900s Phragmites australis has been replacing other vegetation in Atlantic and Gulf coast marshes at a rate of about 1% to 6% of the marsh surface per year. Vast areas of coastal marsh are now characterized by dense monotypic stands of this species. By virtue of its ability to build up the marsh surface, P. australis affects the landscape, hydrology, and hydroperiod of the marsh as well as drainage density, and other geomorphic features. Smoothed microtopography results in more difficult access to the marsh by nekton, and possibly reduced exchange of organic materials between the marsh and adjacent estuary. The pattern of replacement by Ti australis results in fragmentation of existing stands of Spartina alterniflora and other extant macrophytes, thereby altering landscape ecology and the ability of the marsh to support biodiversity and the production of marsh fauna.