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Salt marsh pools are shallow, steep-sided depressions that remain flooded throughout a tidal cycle and provide important habitat for nekton (fish and decapod crustaceans). Although New England pools are relatively unstudied, efforts are underway to expand pool habitat through an open marsh water management technique known as ditch plugging. The purpose of this study was to quantify pool geomorphic and geographic characteristics, to determine distribution of vegetative cover types and nekton species, and to evaluate effects of ditch plugging on nekton use of pools. Over 30 ditched and unditched marshes were surveyed from the Connecticut shore of Long Island Sound to southern Maine, USA for pool physical traits. Pools from ditched and unditched marshes had similar sizes, depths, and distances to tidal flow, but pool density (#/ha marsh) and coverage (m pool/ha marsh) were over twice as great at unditched versus ditched marshes. Ditch intensity (m ditch/ ha marsh) was negatively correlated to pool density and coverage. Pool vegetative cover was surveyed at 12 New England marshes using 0.25 m quadrats and the Braun-Blanquet scale for coverage estimation. Eight cover types were identified with the most common being "bare" (pool bottom visible), filamentous green algae, algal flocculation, and Ruppia maritima. Pool cover types varied by region, with bare more prevalent at northern sites. Canonical correlation analysis indicated that environmental conditions supporting R. maritima and algal floe coverage were distinguished by water depth, soft sediment depth, and water column nitrogen concentrations. Pool nekton sampling using 1 m throw traps in 1999 and 2000 documented 12 fish and 4 decapod species with Fundulus heteroclitus comprising 80% of the fish catch. Species richness and density were greater in southern than in northern New England sites. In contrast to results from other studies, fish densities were not affected by the presence of submerged aquatic vegetation (R. maritima). Data suggested that F. heteroclitus use pools as nursery habitat and as refuges from predation, selecting among pools with different environmental conditions as the season progressed and juvenile size increased. Restoration efforts, therefore, should maintain a range of pool conditions to support a diverse nekton community and its changing needs. The effects of ditch plugging at 3 salt marshes in the Rachel Carson National Wildlife Refuge, Maine, USA, were evaluated using a BACI (Before-After-ControlImpact) study design. Throw-trap sampling produced a total of 7 fish and 3 decapod species in salt marsh pools with F. heteroclitus accounting for 89% of the fish catch. After controlling for natural variation using the BACI design, nekton community and total fish density remained unaltered at Moody and Granite Point. Decreased species richness at Granite Point marsh was thought due to physical barriers created by ditch plugs and a 51 % reduction in tidal interface. At Marshall Point, ditch plugging resulted in increased pool habitat and nekton use at the experimental versus control area pools. Both fish and decapods occupied newly created pools within weeks and within months new pools were not different from old pools in terms of nekton use. This study documents only initial nekton response to ditch plugging; longer term monitoring is necessary to ensure achieving management goals. ACKNOWLEDGEMENT This study was supported by the USGSBiological Resources Division, administered through the Patuxent Wildlife Research Center, Coastal Field Station at the University of Rhode Island. My deepest thanks also to the USFWS for promoting this research and to the staff at Rachel Carson National Wildlife Refuge for their support and for providing exquisitely beautiful study sites. My gratitude extends particularly to Jan Taylor, USFWS; Ward Feurt, Rachel Carson National Wildlife Refuge; and Mike Morrison, SW AMP, Inc. Thanks also to all those who braved summer heat and autumn chill to help with field work especially Susan Williams, Brandi Bomt, Kenny Raposa, Mike Adamowicz, Sean Ballou, MJ James-Pirri, Ryan Taisch, and Linda Longo. Charles Roman is the best advisor a graduate student could hope to find . Thank you for your support, reality checks, field assistance, and introduction to Fat Boys in Maine. Your ecological and editorial insights have proven critical. Thank you for your patience and your good sense of humor. Thank you for carefully reading all those rewrites and for keeping high standards. My sincere appreciation goes to Candace Oviatt who encouraged me to stop messing around and just get the Ph.D. Your support came at a time when I doubted even the simplest things. Thank you for your staunch backing. James Heltshe opened the world of statistics and proved great help throughout the course of this study. Any mistakes in that realm, however, are my own. Michael Pilson and Peter August also have my gratitude for their help and insights during my studies and particularly for their assistance as committee members.

New England Salt Marsh Pools: Analysis of Geomorphic and Geographic Parameters, Macrophyte Distribution and Nekton Use