SYBIL CREEK RESTORATION Baseline Data and Habitat Assessment Prior to Restoration COVER PAGE FOREWORD & ACKNOWLEDGMENT INTRODUCTION Sybil Creek Baseline Sampling Report • Map of Study Site • Marsh Restoration • Historic Background • Purpose & Goals • Site Conditions BASELINE SAMPLING RESULTS • Transect Location Map • Hydrology • Nutrients • Vegetation • Surface Sediments • Peat Bulk Densities • Palynology • Birds • Mammals • Amphibians & Reptiles • Fish LITERATURE CITED PHOTOS Photo Location Map This study was funded by a grant to the Branford Land Trust by the Long Island Sound License Plate Fund. < Back to BLT Main Site

Hydrology
Examples of continuously recorded water table levels for the restricted (Transect #3) and unrestricted (Transect #1) marsh are shown in Figs. 3 (restricted marsh) & 4 (unrestricted marsh). Spring (first 4 days) and Neap (last 11 days) tidal cycles are reflected in the water table changes for the unrestricted marsh. As expected, the high marsh experienced lower tidal amplitude than the low marsh, which flooded more frequently and had a shallower water table below the surface. The influence of the tide gate on tidal activity in the restricted marsh is evident by the lower water table change in the restricted marsh compared to the unrestricted marsh. In contrast to the restricted high marsh, the restricted low marsh did flood for a brief period during early March, 2000. With the exception of this flooding episode the subsurface water table fluctuations for the high restricted marsh were larger than the low restricted marsh and followed a diel pattern. The high restricted marsh is dominated by Phragmites, whereas the low restricted marsh on this portion of Transect #3 is dominated by S. patens. Daily water table drawdown resulting from high rates of evapotranspiration by Phragmites would explain most of the observed pattern at the high restricted marsh.

Figure 3. Hydrolic data collected in the restricted marsh during the March, 2000 sampling period. Data obtained from measurements of wells along Transect #3.

Figure 4. Hydrolic data collected in the unrestricted marsh during the summer of 1999. Data obtained from measurements of wells along Transect #1.

The hydrology data collected during March 2000 at the restricted marsh and from June - September 1999 at the unrestricted marsh are summarized in Table 2. The mean flooding depth and duration (calculated from the individual flooding episodes recorded continuously for two week time periods) was significantly greater at the low unrestricted marsh relative to the high unrestricted marsh. Flooding depth in the restricted low marsh, during the few episodes in which it was flooded, was similar to depths in the unrestricted marsh recorded the previous summer. Flooding duration, however, was lower in the restricted marsh relative to the unrestricted marsh.

Table 2. Sybil Creek Hydrology Data - Unrestricted and Restricted Wells.