A Meta-analysis of Nekton Responses to Restoration of Tide-Restricted New England Salt Marshes

Abstract

Salt marsh landscapes provide a mosaic of valuable habitats for a diverse array of estuarine nekton (defined here as free-swimming fish, shrimp, and crabs). Different species and life-history stages of nekton use salt marshes for foraging (Allen et al. 1994; James-Pirri et al. 2001; McMahon et al. 2005; Nemerson and Able 2005; Shervette and Gelwick 2007), overwintering (Smith and Able 1994; Raposa 2003), spawning (Taylor et al. 1977; Kneib 1997), as nurseries (Talbot and Able 1984; Rountree and Able 1992; Able and Fahay 1998; Minello et al. 2003), and as a refuge from predation (Kneib 1987; Minello 1993; Kneib 1997). Nektonic marsh species in turn play an important ecological role in adjacent estuaries by physically transporting energy from salt marshes into deeper estuarine habitats (Cicchetti and Diaz 2000; Deegan et al. 2000). Marsh nekton are also the primary prey items of economically valuable fishery species (e.g., Grant 1962; Nelson et al. 2003; Gartland et al. 2006) and charismatic estuarine birds such as herons and egrets (e.g., Parsons and Master 2000; McCrimmon et al. 2001). The importance of salt marshes to nekton is well documented, and the link that nekton forges between marshes and estuaries is clear. Unfortunately, human activities have long compromised the direct, physical connections between salt marshes and estuaries that are essential for nekton transport.