Production and Field Planting of Vegetative Propagules for Restoration of Redhead Grass and Sago Pondweed in Chesapeake Bay

BACKGROUND: During the last several decades, seagrasses and related submerged aquatic vegetation (SAV) have been lost from shallow waters of Chesapeake Bay (Orth and Moore 1983) and other coastal ecosystems worldwide (Short and Wyllie-Echeverria 1996). Losses of SAV beds are of particular concern because these plants tend to create rich habitat and food for animals, supporting growth of diverse fish, invertebrate and waterfowl populations (e.g., Kemp et al. 1984; Orth and van Montfrans 1990; Heck et al. 1995). In the mesohaline portion of Chesapeake Bay, historical SAV abundance, which had been decimated by the late 1970s, has gradually increased from the mid-1980s to present levels. Compared to historical SAV communities in this region, however, the number of recovering plant species has remained depressed, with one species, Ruppia maritima (widgeon grass), predominating throughout (Orth et al. 1997). This “pioneer” SAV species is an annual plant with prolific production of viable seeds and high growth potential (Silberhorn et al. 1996; Stevenson et al. 1993; Kautsky 1988). More stable species, like Potamogeton perfoliatus (redhead grass) and Stuckenia pectinata (sago pondweed), that had previously represented a large component of the SAV community in mesohaline areas of Chesapeake Bay (Stevenson and Confer 1978), are presently scarce in this region (Moore et al. 2000; Orth et al. 1997).