SALT MARSH VEGETATION AND NEKTON COMMUNITY MONITORING AT ASSATEAGUE ISLAND NATIONAL SEASHORE
2008 Summary Report
Natural Resource Report
NPS/NCBN/NRDS—2010/065

Erika L. Patenaude
Penelope S. Pooler
National Park Service
Northeast Coastal and Barrier Network
University of Rhode Island
1 Greenhouse Rd
Kingston, RI 02881

August 2010

U.S. Department of the Interior
National Park Service
Natural Resource Program Center
Fort Collins, Colorado
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Executive Summary

The Northeast Coastal and Barrier Network (NCBN) is one of 32 networks of parks created by the Inventory and Monitoring Program (I&M Program) of the National Park Service. The I&M Program has two components, 1) to collect baseline ecological inventory datasets and 2) to implement Vital Signs monitoring, a long-term ecological monitoring program, in each of the Network parks. The Northeast Coastal and Barrier Network consists of eight parks linked by geography and shared ecological characteristics along the Northeastern Atlantic Coast. As part of the Vital Signs program, each Network has developed detailed protocols for monitoring a select number of Vital Signs, or ecological indicators. Because the majority of parks in the NCBN are coastal parks, salt marsh monitoring was chosen as a high priority and a protocol was developed for collecting long-term data on salt marsh vegetation and nekton (James-Pirri In Development--a, b).

This annual report summarizes the first year of data collected at Assateague Island National Seashore (ASIS) located in Maryland and Virginia. Fifty vegetation plots and a subset of pools, creeks and shoreline were sampled for nekton at nine marshes June-September, 2008. Monitoring data is to be collected at these same marsh sites biennially. Nekton in marsh pools, large tidal creeks, and shoreline habitats (all less than 1m deep) were sampled with a 1m2 aluminum throw trap (Kushlan 1981, Sogard & Able 1991, Raposa and Roman 2001). Vegetation was monitored using 1m2 plots and a revised Braun-Blanquet method (Kent and Coker 1992) to estimate percent cover of each vegetation species and non-vegetation cover type within each plot.

At the nine ASIS sites, 27 vegetation species along with 5 non-vegetation cover types were recorded during vegetation sampling in 2008. Non-vegetation cover types recorded included horse manure, wrack and litter, bare ground, water, and trash. Seventeen species of nekton were recorded at ASIS in 2008, including 15 fish species, 1 crab species, and 1 shrimp species. Examination of percent catch data indicates that four fish species account for approximately 94% of all nekton captured. The most prevalent species, sheepshead minnow (Cyprinodon variegatus), accounts for approximately 66% of all nekton recorded at ASIS in 2008. The other three species, common mummichog (Fundulus heteroclitus), rainwater killifish (Lucania parva), and inland Silverside (Menidia beryllina), account for approximately 10%, 9% and 9% respectively.

The information collected through this long-term monitoring program will equip park managers with scientific data to make informed decisions on both the aquatic and terrestrial resources they manage. This report summarizes the 2008 baseline data for ASIS salt marshes. Changes in salt marsh condition will be examined following data collection in 2010. By understanding the changes or trends occurring in salt marsh vegetation and nekton communities, managers will be able to better adapt and respond to these changes through their management practices.

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