from 1995 to 1999. Wilcox et al. (2003) hypothesize that expansion will continue quickly 
through the Great Lakes. In addition, Bertness et al. (2002) demonstrate that increased nitrogen 
from shoreline development is facilitating expansion of Phragmites across New England salt 
marshes. 
Phragmites control activities are important for wetland restoration projects. Methods to 
control Phragmites include biocontrol, flooding, non-specific herbicide control, cutting, and/or 
burning (Ailstock et al., 2001). Most states carry out herbicide applications in conjunction with 
other management techniques, such as mechanical removal, burning, or induced tidal flooding. 
Ohio, Delaware, and Virginia have had success applying herbicides aerially, and other states are 
considering this method. Several states carry out herbicide control measures on private lands 
through cost-sharing programs or through financial and technical assistance. Virginia has 
mapped Phragmites distribution within the state and uses this information to prioritize control 
and management actions. 
Climate change may affect Phragmites control. Phragmites can tolerate brackish but not 
saline water (Asaeda et al., 2003), and therefore, sea level rise may help control this species and 
increase restoration success of some coastal wetlands. Areas predicted to be inundated by 
saltwater and to experience increased frequency of saltwater intrusion due to climate change may 
not be priority target areas for control actions. However, Phragmites populations also increase 
with higher-than-average ambient air temperatures (Wilcox et al., 2003), and thus other wetland 
areas may need to increase their control activities. 
2.5.4. Green Crab 
Invasive species have been introduced into marine ecosystems via a variety of vectors: 
ballast water and other shipping vectors; pet, aquaculture, and aquarium releases/escapes; 
opening of seaway canals between water bodies; and, to a lesser extent, research activities 
(Fofonoff et al., 2003; Siguan, 2003). The European green crab ( Carcinus maenus) is a well- 
known invasive predator on both the western and eastern U.S. coasts and in various coastal 
regions of South Africa and Australia (Grosholz and Ruiz, 1996). The crustacean damages 
coastal fisheries by consuming juvenile native bivalves (Glude, 1955; Walton et al., 2002; Floyd 
and Williams, 2004). It is difficult to control and manage green crab populations. Lafferty and 
Kuris (1996) recommend developing and implementing biocontrol methods, although a 
biocontrol agent is currently not available (ANSTF Green Crab Control Committee, 2002). 
Maine has attempted physical control through fencing and manual control such as selective 
harvests, but the state has not been successful at controlling the green crab. In Maine, winters 
with below average temperatures have been the only thing that has succeeded in diminishing 
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