East River Shellfish Monitoring

Under the directive of SHoP Architects and New York City Economic Development Corporation (NYCEDC), One Nature LLC was contracted to collect water quality data and report on site conditions at the EcoPark, an intertidal habitat slab located within the East River Waterfront Esplanade (ERWE) – a two-mile waterfront open space on the East River in Lower Manhattan. This report provided data from six months of bi-monthly water quality samples (May-November, 2014). In addition, One Nature analyzed results, discussed biota recruitment patterns, and offered recommendations for further establishment. This report was prepared for the New York Department of State with funds provided under Title 11 of the Environmental Protection Fund.

There was limited recruitment of mussels to the site, despite generally favorable water quality conditions. They tended to be found in niches between the rocks and in protected areas in the back (upriver) of the habitat, which would appear to be suitable habitat for them. Reasons for the limited recruitment may include relatively little supply of larvae from elsewhere in the NY Harbor area. Other organisms settled into the rocky area, including hydroids, sea anemones, and crabs (native rock crabs and non-native Asian shore crabs). These crabs eat mussels, and predation could be one reason why mussel populations did not increase.

Very few animals of any kind recruited onto the slab, which became covered instead by algae, beginning with the green algae, Entermorpha, and succeeding to an eventual dominance by Ulva lactuca. The lack of mussel recruitment to the slab is likely due to the lack of protection it provides for settling larvae which would be swept away by the swift currents of the East River before being able to attach themselves strongly enough. Furthermore, the successive combination of the green algae, Entermorpha and then Ulva, may have occupied potential settling locations for larvae looking to establish.