Mollusk Restoration around Wastewater Treatment Plant (NY) # Progress Report: August 26, 2011

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1 To date, the project has involved numerous teleconferences, s and permitting exercises with the goal of ribbed mussel seed collection, construction and installation of a mussel raft in the Bronx/East River, and initiation of activities to seed the raft in and study the growth and physiology of ribbed mussels and seaweed cultures and their effects on water quality. Milestone 1. Ribbed mussel seed collection in the intertidal zone. On May 23, 2011, coir mats and logs were deployed in the Bronx River with Carter Newell and Rocking the Boat staff and Program Assistants. The mats were located in two areas across from Hunts Point Riverside Park, at the lower intertidal zone: one adjacent to a bed of spartina alterniflora, and one along rocky rip rap. Wild ribbed mussels were observed in both locations. In the first location, 30 feet x 8 feet wide coir mats were pinned to the mud, and 3 coir logs were pegged and tied to the sediment. In the second location, 70 feet x 8 feet wide coir mats were pinned to the mud, and 6 coir logs were pegged and tied to the sediment. Their ability to attract ribbed mussel seed will be monitored throughout 2011 and Carter Newell also gave a presentation on mussel biology and culture to the RTB students in May. Ribbed mussels along the rocks in the Bronx River

2 Coir logs and mats at the second location in the Bronx River

3 Coir logs and mats at the first location in the Bronx River Coir logs and mats at the second location in the Bronx River

4 Ribbed mussels and eelgrass along the east shore of the Bronx River

5 RTB staff and intern loading up the coir mat and logs for deployment. Milestone 2. Raft assembly and deployment. In August of 2011, a 20x20 foot mussel raft brought down in late winter from Maine was assembled by Carter Newell and assistant, and Rocking the Boat staff and Environmental Program Assistants. The floats were bolted to wooden cross-member beams, lumber was fixed to the raft for walkways and support, and the raft was lifted into the water by Rocking the Boat neighbor SIMS Metal Management using a crane. It was towed to the designated site and moored using the anchoring system consisting of 4 x 300 lb anchors each with 50 feet of bar link chain and 75 feet of mooring line with a buoy attached to the chain and a tension buoy attached to the line near the raft. The vessel tensioned the mooring system near low tide to approximated 150 lbs. of torque on each mooring line. Soon after, RTB staff and apprentices deployed 20 coiled and 20 uncoiled ropes on the raft for seed collection, as well as lines that had been previously placed in the water from June to July to test for mussel spatfall. As of August, no wild mussel seed were observed on either the coir or the mussel ropes, but sea squirts were abundant on the mussel ropes.

6 Anchors for the mussel raft delivered to RTB

7 Raft assembled in the yard at RTB with mooring lines attached

8 Lowering the mussel raft into the river Mussel raft in place at the designated location Future plans Final arrangements are being made for the deployment of seaweed lines along the east and west sides of the raft. Wild seed will be collected in September to attach to the ropes using biodegradable cotton binder. The spat collection study will continue along with physiological studies of ribbed mussels at the study site.