Oyster Research in the Hudson River Estuary

Oyster Research History

Oysters were once a very abundant and cherished resource of the Harbor estuary, but by the early 20th century, sediment and water pollution and overharvesting had all but eliminated these once dominant creatures. While only a few small patches of oyster reef remain today, water and sediment quality has dramatically improved, making the restoration of the Eastern oyster (Crassostrea virginica) possible. For the past decade, the Hudson River Foundation has been working with partners to study, design, and test oyster restoration techniques suitable for the diverse environs of the Harbor Estuary.

Oyster Restoration Research Partnership (ORRP)

The ORRP was formed by the Hudson River Foundation to bring together academic, government, and private entities to deepen scientific understanding of oysters reintroduced into the NY/NJ Harbor Estuary. Partners collaborate on research projects and share data on research experiments and pilot oyster restoration projects. The partners meet regularly as part of the NY-NJ Harbor Estuary Program’s (HEP) Oyster Restoration Work Group.

Soundview Park

Primary Project Collaborators: Billion Oyster Project, NY/NJ Baykeeper, New York City Parks, The Hudson River Foundation, The University of New Hampshire, Bronx River Alliance Rocking the Boat

One of the first oyster research sites in the Hudson River Estuary, Soundview Park remains an active oyster research site where scientific researchers, government agencies, not-for-profit groups, and community members come to study oysters, test restoration techniques, and learn about shallow subtidal oyster reef restoration in the New York Harbor.

From 2009-2012, the Oyster Restoration Research Project (ORRP) Phase I multi-site effort assessed reef development and performance at five experimental reef sites. The ORRP Phase I effort was followed from 2012-2014 by the Community Based Restoration Project in the Bronx River, off Soundview Park.

The current five acre project builds on more than a decade of previous work by the partners. Once completed, the Soundview Oyster Habitat Restoration Project will be the largest oyster restoration project in NYC, with over 600 cubic yards of recycled oyster shells from NYC restaurants and over 225 oyster gabion reefs. The Hudson River Foundation and partners from the University of New Hampshire sampled the benthic community prior to the reef construction, and will monitor the change in the both the benthic and epibenthic community from the project. The team will also monitor oysters in the gabion cages and the newly installed shell reefs to gain insights into how these reefs are developing over time. Monitoring metrics will be used to evaluate the newly planted oysters and determine how well they are growing,surviving, and recruiting new oysters to the reefs.

Community Based Restoration of Oyster Reef Habitat in the Bronx River: Assessing Approaches and Results in an Urbanized Setting

Lodge, J., Grizzle, R., Coen, L., Mass Fitzgerald, A., Comi, M.,. Malinowski, P. 2015. Final Report of the NOAA/WCS Regional Partnership Grant, New York, NY.

This project continued and expanded on the previous smaller-scale multi-site effort of the Oyster Restoration Research Project (ORRP). Project partners focused on the development of general protocols for shallow subtidal oyster reef restoration in the New York Harbor region where natural reefs and recruitment of native eastern oysters (Crassostrea virginica) are uncommon. The primary aim of the multi-year (2012 -2014) effort was: (1) the construction; (2) monitoring; (3) involvement of community partners; and (4) development of novel methods, including adaptive management, ultimately restoring an approximately one acre footprint of productive oyster reef habitat at the confluence of the East and Bronx Rivers, off Soundview Park.

Project Collaborators: The Hudson River Foundation (J. Lodge), NY/NJ Baykeeper (M. Comi, Dr. A. Mass Fitzgerald), Urban Assembly New York Harbor School (P. Malinowski), NY Harbor Foundation, University of New Hampshire (Dr. R. Grizzle), Florida Atlantic University/HBOI (Dr. L. Coen)

Supporting Partners: Bronx River Alliance (L. Cox, D. Griffin), NYC Department of Parks and Recreation, Natural Resources Group (M. Larson, S. Tobing, K. Conrad), Public Lab (L. Barry), Rocking the Boat (A. Green, S. Marquand, C. Ward), NY and NJ Harbor and Estuary Program (K. Boicourt), USACE (L. Baron, P. Weppler).

Tappan Zee Bridge

Partners: Billion Oyster Project, the Hudson River Foundation and the University of New Hampshire

The Tappan Zee project represents the most successful oyster reef restoration project implemented in the Hudson River Estuary. The project exceeded all previous projects in terms of restored area and several metrics of early restoration success. Based on October 2020 sampling results at the close of this study, an estimated total of 5.8 million live oysters had colonized the deployed substrates at the project sites. The Tappan Zee Bridge oyster mitigation project was preceded by a 3-year pilot study assessing the performance of three potential restoration substrates, 1) metal gabion cages containing oyster shells, 2) small Reef Balls (“Lo-Pro”), and 3) larger Reef Balls (“mini-bay ball” style), at several potential restoration sites. The pilot study determined that Mini-Bay reef balls and shell-filled gabions provided effective substrates, and were chosen for the full-scale reef restoration efforts.

NYC Department of Environmental Protection’s Jamaica Bay Oyster Restoration Pilot Project

New York City Department of Environmental Protection. 2020. Developing a Self-Sustaining Oyster Population in Jamaica Bay, New York City. Grant 41931 Final Report.

The Hudson River Foundation is participated in a 3-year (2016-2019) oyster research pilot study in partnership with the Billion Oyster Project, Cornell Cooperative Extension, HDR Engineering, and the University of New Hampshire. The project was directed by the NYC DEP and primarily funded with a grant from the U.S. Department of Interior being administered by the National Fish and Wildlife Foundation (NFWF).

The major objective of the research project was to test a new approach to enhancing recruitment to constructed oyster reefs where natural recruitment is low or does not occur. The researchers hypothesized that enough of the free-swimming larvae that will be produced by the 50,000 adult oysters growing in the newly installed Oyster Nursery a few hundred feet away will find their way to the constructed reefs.

This hypothesis was not supported by this study as there was no observed recruitment of oysters to the receiver reef or evidence of spat settlement in the surrounding area. Results of the study do not suggest that proximity to a healthy reef (population of adult oysters) is unimportant in siting reef restoration projects. Rather, the finding that no oyster recruitment was observed on any of the spat collectors in the Head of Bay area, suggests that the oysters held on the donor reef did not produce larvae that successfully recruited to the benthos in the study area.

Partners: Billion Oyster Project, Cornell Cooperative Extension, HDR Engineering, Inc., the Hudson River Foundation and the University of New Hampshire

Experimental Oyster Reef Development and Performance Results: Phase 1

Grizzle, R., K. Ward, J. Lodge, K. Mosher-Smith, K. Kalchmayr, & P. Malinowski. 2013. ORRP.

This report describes the results of the Oyster Restoration Research Project (ORRP) Phase I (2010-2012) studies to assess development (oyster retention, growth and survival) and performance (water filtration and habitat provision) at five experimental reef sites (Bay Ridge Flats, Governors Island, Hastings, Soundview and Staten Island). This report also provides an assessment of where additional efforts should be focused and questions that need to be answered. Because the constructed experimental reefs essentially replaced the habitat that existed at the time of construction, there is a need to understand these changes on the broader ecosystem. Thus, another objective of the ORRP Phase 1 studies was to evaluate “habitat substitution” by comparing the faunal benthos before and after reef construction.

Hudson River Foundation