1a.Objectives (from AD-416):
Develop technology and methodology for both passive and active acoustic applications to improve the production and profitability of aquaculture in the United States. This includes the use of ultrasound to mechanically clean water, utilizing acoustic stimuli on catfish to improve seining operations and passive acoustic monitoring of small fry. This project supports the unit objective to develop new equipment and technologies to improve profitability of channel catfish farming.
1b.Approach (from AD-416):
Preliminary acoustic measurements of commercial algae control systems will be made in the National Center for Physical Acoustics (NCPA) calibration tank. Customized equipment will be assembled at the NCPA and delivered to National Warmwater Aquaculture Center (NWAC) for lab and field trials by USDA personnel. Measurements on fish stimuli with sound will be made at USDA-NWAC tanks and ponds with later trials performed in conjunction with seining to determine effectiveness. Equipment for passive monitoring of catfish fry will be assembled at the NCPA. Measurements will be made by NCPA personnel at USDA-NWAC facilities.
The purpose of this agreement is to investigate active and passive acoustic techniques to improve the profitability of U.S. aquaculture. Work progressed on the use of sound to move fish in advance of seine nets to improve harvesting. Using sounds previously found to be annoying to fish, direct assessments were made on ponds during seining. Numerous ponds at Delta Western Research Center, in Indianola, MS, were seined with and without the use of sound emissions. The results indicated that the use of sound did not statistically increase the number of fish. While the literature provides numerous examples of using sound to alter fish behavior and movement, those examples were not moving fish toward some other perceived danger. It is presumed that being captured in the net was more of perceived threat than the annoying sound. Experiments were also conducted at the University of Mississippi to investigate the observation that exposure to high amplitude ultrasound may mortally wound a significant percentage of snails and to determine the optimum duration of exposure. Results from the tests run on snails collected in the summer of 2012 are very promising, with one experiment indicating a mortality as high as 85% one week after exposure, compared to 30% of the non-exposed snails. Continued experimentation is planned throughout the summer of 2013.