This working paper was prepared for the Secretariat of the Commission for Environmental Cooperation (CEC) and the Global Programme of Action Coalition for the Gulf of Maine (GPAC). The views contained herein do not necessarily reflect the views of the CEC, or governments of Canada, Mexico or the United States of America. Reproduction of this document in whole or in part and in any form for educational or non-profit purposes may be made without special permission from the CEC Secretariat, provided acknowledgement of the source is made. The CEC and the Wells National Estuarine Research Reserve would appreciate receiving a copy of any publication or material that uses this document as a source. Published by the Wells National Estuarine Research Reserve For more information about this report or to obtain additional copies contact: The Wells National Estuarine Research Reserve Research Department 342 Laudholm Farm Road Wells, ME 04090 Tel: (207) 646-1555vFax: (207) 646-2930 E-mail:
[email protected] Internet: http://www.wellsreserve.org For information about this or other publications from the CEC, contact: Commission for Environmental Cooperation 393, rue St-Jacques Ouest, bureau 200 Montreal (Quebec) Canada H2Y 1N9 Tel: (514) 350-4300vFax: (514) 350-4314 E-mail:
[email protected] Internet: http://www.cec.org Cover Photo Collage Background photo: mid-tide in an unaltered salt marsh (i.e., no tidal restrictions). Foreground photos clockwise from top right: wading birds foraging in a salt marsh panne; volunteer sampling vegetation on high marsh (orange color of grass indicates a fall rather than a summer sample date); road crossing with undersized culvert alters hydrology, functions and values of upstream marsh (photo taken at low tide in early spring); the mummichog (Fundulus heteroclitus) plays an important role in the marsh food web; Phragmites australis (commonly referred to as Phrag), a brackish marsh plant that can become invasive in salt marsh areas where elevations and/or hydrology have been altered.