Indicators of recovery in a tropical freshwater marsh invaded by an African grass.
Antelope grass (Echinochloa pyramidalis) is an African grass species used for cattle grazing in Mexican wetlands. It has been introduced because of its tolerance to flooding and is now a widespread invasive. In this work, we present the advances of a freshwater marsh restoration project represented by bulltongue (Sagittaria lancifolia) but invaded by antelope grass. This project began in 2007 with the goals of eliminating antelope grass and other problematic species, increasing the cover of the native vegetation, and recovering habitat for waterfowl. Two sets of controls were established (in the remaining marsh and the inundated grassland) along with three other managed sites (variations of clipping by hand, drowning the cut plants, burning, covering with black plastic, or selectively applying herbicide). With two years of restoration activities, the antelope grass was almost completely eliminated, remaining only in one control set. The dry conditions of 2009 have favored the resprouting of the invader, but it still has low cover values. Pickerelweed (Pontederia sagittata), cattail (Typha domingensis), and bulltongue have appeared with high cover values in most of the quadrats in almost all sites. Plant species richness has increased with time. Amphibians and reptiles have varied through time but are showing a slight increasing trend.