1. The application of stereo-video technology for the assessment on population change of black rockfish Sebastes schlegeli in a vessel reef area in Haizhou Bay, China.
- Author
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Liu, Hui, Xu, Qiang, Xu, Qinzeng, Zhang, Yingqiu, and Yang, Hongsheng
- Subjects
THORNYHEADS ,ARTIFICIAL reefs ,BIOMASS ,UNDERWATER acoustics ,DEMOGRAPHIC change - Abstract
The assessment of population structure and abundance of fish assemblages associated with artificial reefs (ARs) is an important aspect of AR management. In the present study, we used a Dive-Operated Stereo Video (stereo-DOV) technique to assess the population structure and abundance of Sebastes schlegeli associated with two metallic, and three wooden, vessel reefs in Haizhou Bay during 2012 and 2013. The study used video systems to obtain length measurements and estimates of abundance. The size composition of S. schlegeli differed among reefs and individuals around vessel reefs were all adults, with total lengths (TL) of >20 cm. Juvenile fish were encountered by divers in a rocky area near the island away from the vessel reefs. The largest individual S. schlegeli (with the highest TL) among five reefs were found around a metallic vessel reef in both 2012 and 2013. TL of S. s chlegeli from all reefs increased by an average of 3.2 cm ( P<0.05) from 2012 to 2013, with an estimated mean weight increase of 250.4 g ( P<0.05). The video survey also indicated a decrease in the biomass of schools near two metallic vessels between the years. Stereo-video technology was found to be suitable for rockfish surveys around the reefs. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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