Rationalization of Set Net Fishery by Radio Transmission System for Underwater Video Image

Accession number;06A0177343
Title;Rationalization of Set Net Fishery by Radio Transmission System for Underwater Video Image
Author; AKIYAMA SEIJI (Tokyo Univ. Marine Sci. and Technol., JPN)
Journal Title;Fisheries Engineering
Journal Code:F0449B
ISSN:0916-7617
VOL.42;NO.3;PAGE.213-217(2006)
Figure&Table&Reference;FIG.6, TBL.1, REF.14
Pub. Country;Japan
Language;Japanese
Abstract;In order to observe of fish behavior to the set net, a radio transmission system for underwater video image was constructed and tested. This system consists of a transmitting station on the sea and a receiving station on the land. The transmitting station is composed of an underwater video camera, a video transmitter, a transmitting antenna, lead-acid batteries, a cellular phone and a sound sensor for remote control of power supply. The underwater video image is transmitted to the receiving station with microwave of 1.2GHz. The receiving station is composed of a receiving antenna, a video receiver, a monitor and a VCR. The maximum transmission distance of the system was measured with about 7km on the sea. The test run of the radio transmission system for underwater video image was conducted on the set net fishing ground in Tateyama Bay, Chiba Prefecture. The underwater video camera was installed in front of a funnel net to observe the fish behavior to the final trap of the set net. The transmitting station was moored near the final trap and the recciving station was set up in the Banda Marine Laboratory of Tokyo University of Fisheries where is 1.5km away from the set net. The test run lasted for 23 days in November, 2002. A total of 60 hours of the underwater video image were recorded and the fish behavior of 18 species were observed clearly during the test run. The inshore fish such as rudderfish Kyphosus vaigiensis, filefish Stephanolepis cirrhifer and blackfish Girella punctata frequently swam in and out the final trap through the funnel net. In contrast, yellowtail Seriola quinqueradiata did not escape from the final trap except for only one fish. The radio transmission system for underwater video image is useful equipment for the rationalization of set net fishery. (author abst.)