In 1978, thousands of concrete-filled tires were lowered into the ocean off Yarmouth, Massachusetts, forming the start of an artificial reef that has continued developing in Nantucket Sound for decades, The Times of India reported.
The project was designed to create physical obstacles on the sandy seabed and provide habitat for fish and lobsters. The reef eventually grew to about 2,500 original units spread across 127 acres, roughly 51 hectares, with later additions bringing in concrete and granite.
A 2019 study gave researchers another way to measure how well the reef was working, finding a striking difference in how quickly fish found the structured habitat compared with bare sandy seafloor nearby.
First permitted artificial reef of its kind
The Yarmouth reef was designed by the town's Department of Natural Resources with assistance from the Division of Marine Fisheries. It became the first permitted artificial reef of this type in Massachusetts and sits more than two miles, about 3.2 kilometers, south of the mouth of the Bass River.
The earliest structures were fairly simple. Three to five tires were filled with concrete and bundled together, forming a low structure above the seafloor. About 1,500 of these units were lowered into the water in 1978, with another 1,000 added in 1994, bringing the total to roughly 2,500.
The goal was to add physical complexity to an otherwise fairly uniform stretch of seabed, giving fish and lobsters places to shelter and move around. The Massachusetts Artificial Reef Program describes such structures as deliberately placed fish habitat that can benefit fisheries, including recreational fishing.
Little sign the structures had shifted
Surveys carried out by the Division of Marine Fisheries in 2009 and 2010 used side-scan sonar and divers to examine the site. They found little evidence that reef material had moved outside the permitted area.
The northern part of the site held the highest concentration of placed material, and fish numbers were also higher where reef structure was denser. Scup and black sea bass were among the fish found in significant numbers. The Massachusetts Artificial Reef Program uses surveys, dives and remote sensing to track how these sites function and how marine communities develop around them.
How quickly fish found the reef
In the 2019 study, researchers compared the Yarmouth reef with another artificial reef, a natural reef and a site of relatively uniform seafloor. Underwater video cameras were used to record when fish arrived at each location.
The difference in arrival time was striking even without dramatic interpretation. Bony fish appeared on camera after an average of about 33 seconds at the reef sites, compared with 502 seconds, roughly eight minutes and 22 seconds, at the bare control site. The study found fish appeared at reef sites 93.4% faster than at the bare stretch.
That did not mean all reefs performed identically. The study also measured species richness and diversity at Yarmouth, at a site in Harwich, at the natural reef and at the bare control area. Black sea bass and scup were recorded at every site, though researchers found differences in fish community composition depending on location and the age of the reef.
Shelter and surfaces for marine life
Part of the value of an artificial reef lies in the spaces created around and between its structures. A flat sandy bottom has relatively little vertical relief, while connected structures create edges, gaps and surfaces where animals can hide, feed or attach themselves.
The Yarmouth site has been linked to a range of marine life, including black sea bass, scup, tautog, summer flounder, winter flounder and lobsters. Other species recorded at the reef include mussels, cunner, butterfish, longfin squid and whelk.
In this way the reef became more than a collection of objects placed underwater. Marine organisms gradually colonized the available surfaces, and fish used the added structure as part of their surrounding environment. Massachusetts planning documents on artificial reefs describe earlier observations at Yarmouth showing the structures stabilizing, becoming colonized by marine life, and recreational fishing increasing around the site.
New material keeps changing the reef
The original 1978 placement was not the end of the project. In 2014, the town and the Division of Marine Fisheries received permits to add further reef material in parts of the site where surveys had found a lower concentration of existing structures.
More material was added around 2019 and in early 2020, including decommissioned concrete sinkers from US Coast Guard buoys, granite blocks recovered from demolished structures, and other concrete material. In total, more than 3,000 cubic yards, about 2,300 cubic meters, of new material was used across these two placement phases.
The later additions also changed the character of the reef. Instead of relying only on the original tire bundles, the site began to include approved building and infrastructure materials capable of providing similar physical relief. One Massachusetts state habitat improvement project, for example, used more than 2,200 cubic yards, about 1,680 cubic meters, of material to create additional structured habitat in an untouched part of the reef's permitted zone.
