CINEMar/Open Ocean Aquaculture Annual Progress Report for the period 1/01/03 through 12/31/03

Principal Investigator(s): Michael Chambers, Arthur Mathieson, Larry Harris

I. Accomplishments
As much as $40,000 is spent annually on removal of the fouling community from the two fish cages at UNH's Open Ocean Aquaculture (OOA) site. Removal of these organisms is necessary because of their effects on cage behavior, including the potential for causing the cages to sink to the bottom. Hence, these organisms are viewed mainly as a nuisance by aquaculturists. However, the fouling community potentially removes dissolved nutrients and suspended waste materials from the cages because the community includes plants and suspension feeding invertebrates. The overall goal of this 2-year project is to characterize the development over time of fish cage fouling communities, providing information potentially relevant for designing cage maintenance protocols.

A. Scheduled Tasks
Task 1 - Conduct preliminary (6-month) net panel experiment (completed in year 1)
Task 2 - Provide data for engineering and water quality studies (completed in year 1)
Task 3 - Design and initiate full, 1-year net panel experiment
Task 4 - Characterize the successional sequences of fouling communities on the fish cages
Task 5 - Preliminarily assess the effect of the fouling communities on water quality

B. Progress on Tasks
Task 3 - Design and initiate full 1-year net panel experiment
This task was fully accomplished and the 1-year experiment was initiated when panels were deployed on 20 September 2002. The experiment was designed to characterize short-term sequences initiated at different times as well as a 12-month sequence initiated in September (Figure 1), with the aim of yielding information potentially useful for optimization of the timing and extent of cage cleaning.

Task 4 - Characterize the successional sequences of fouling communities on the fish cages
This task was partially completed in 2003. Identical deployments of net panels were made onto the north cage and onto a frame suspended in the water column nearby which functioned as a comparison site potentially less affected by the existing fouling communities on the cages (Figure 2). Preliminary analysis of most of the panels deployed for 1 month show that potential recruits vary widely throughout the year with spring and fall peaks evident (Figure 3 and Figure 4). There were also dramatic differences most months between the north cage and the comparison site, indicating that existing fouling communities on the cages strongly affect the initial recruitment process.

Replicate panels from 3-month, 6-month, and 12-month sequences for both deployments (north cage and buoy) were retrieved but have not been fully processed (Figure 5 and Figure 6). The 9-month sequences were eliminated from the experiment due to budgetary constraints.

The example panels illustrate two potentially important findings. First, the time of initiation of a successional sequence (which would be simulated by a cage cleaning event) dramatically affects the fouling community after 3 months. Hence, it might be possible to refine the cage cleaning protocol so that it is optimized seasonally. Secondly, in some cases there were substantial differences between the panels on the north cage and the comparison buoy panels, suggesting that the extent to which the cages are cleaned might affect how quickly the fouling communities re-develop.

C. Important Results or Findings
Cage cleaning protocols potentially can be optimized by varying the time of year when cleaning is conducted and the extent to which the cages are cleaned.

D. Difficulties Encountered
Task 5 was eliminated from the work plan because of budgetary constraints.

E. Anticipated Success in Meeting Project Objectives on Schedule
It is anticipated that all project objectives (except task 5) will be met on schedule.

F. Reports, manuscripts, and presentations resulting from the project
The present project led to a collaborative study (funded through NOAA's Small Business Innovative Research program) with ePaint Corporation to assess the effectiveness of various anti-fouling compounds. Phase 1 for this project was completed in 2003, and Phase 2 will be conducted in 2004.

II. Tasks and Activities for Next Reporting period

A. Tasks for the next reporting period
Task 4 - Characterize the successional sequences of fouling communities on the fish cages

B. Brief work plan to accomplish tasks
All remaining samples will be processed and the data analyzed. A final report will be prepared and submitted during 2004.

C. Anticipated concerns or difficulties
None.

III. Expenditures
All expenditures were in the range anticipated for the work accomplished.