Design of a Dredge for Collection of Juvenile Surfclams and Ocean Quahogs

Juvenile ocean quahogs - Arctica islandica
Juvenile ocean quahogs (Arctica islandica – age range 3-10 years).  Collected using a Dameron Kubiak hydraulic clam dredge at Latitude 40 o 48.43’ N, Longitude 72 o 11.23’ W, and depth of 125 feet aboard the F/V Pursuit.  Photo: Roger Mann.

Surfclam and ocean quahog projects containing an at-sea component often require the collection of small clams that routinely are not adequately caught and retained by standard surfclam and ocean quahog dredges. The Dameron-Kubiak dredge designed for the F/V Pursuit solves this problem for the federal survey and projects requiring a large vessel. However, often a smaller, less costly option would suffice.  In the past, to use such a vessel required the laborious lining of the dredge with a mesh insert which, consequently, restricts options at sea and increases mobilization and demobilization costs. This project funded the design and drawings for a custom dredge built to collect juveniles of both SC and OQ in research mode that fits on the smaller F/V Joey D. This survey tool can facilitate critical examination of age structure and recruitment frequency/intensity in both species that would be a necessary component of a wide range of research projects.

The surfclam and ocean quahog fisheries of the Mid Atlantic and Georges Bank regions support productive and sustainable fisheries.  Clam population stock assessment including estimates of standing stock and recruitment is critical to maintenance of the fisheries. Over the past 25 years the clam industry has worked with the National Marine Fisheries Service at Woods Hole and academic partners through the Science Center for Marine Fisheries (SCEMFIS, to ensure data collection on all aspects of the clam life cycle in the regions targeted by fishing activity. A particular focus was given the assessing recruitment, that is clam abundance in year classes too small to be captured by the commercial or survey dredge. This was of particular concern for ocean quahogs that are long lived and may take up to several decades to recruit into the fishery. The industry, working with SCEMFIS, addressed this challenge in 2014 by constructing a research dredge with a variable bar spacing capable of retaining small clams. Termed the Dameron-Kubiak dredge after its designer and fabricator the dredge was deployed from the vessel F/V Pursuit south of Long Island and successfully demonstrated the presence of multiple year classes of pre recruit to fishery size ocean quahogs (see image). 

Fast forward to 2022, and the industry faces imminent challenges with access to traditional fishing grounds as wind farms are developed on that same footprint. Future co-existence on this footprint is an active discussion for all parties. Information on the status of the underlying clam resource is critical to assess wind farm impact. Surveys are necessary for pre-construction, during construction, and ongoing post construction periods. At 160 inches width, the unique Dameron-Kubiak dredge and the support vessel Pursuit are believed to be too large to survey in the wind farm fields post construction. In this difficult situation NJ DEP has stepped forward to fund the construction of a smaller, 100-inch width version of similar dredge design, to be termed the NJ RMI – SCEMFIS dredge. The new dredge was designed by Tom Dameron, drawings prepared by Farrell & Norton Marine Architects, is owned by Rutgers University, and operated from the support vessel Joey D owned by Oceanside Marine of Millville, NJ. This new pairing of a critical sampling tool and a new vessel offer the prospect of continuing high caliber research and survey data that will serve both the clam and wind industries as they work together to ensure future access to and sustainability of the clam resource. 

New Dredge Architectural Drawings by Farrell & Norton Naval Architects (2021) – C779-100C779-101C779-102C779-103C779-104C779-105