Bioacoustic application on fisheries management in an artificial reefs’ ecological reserve of Bohai Gulf China

• Published in: Environmental earth sciences 2018-11, Vol.77 (21), p.1-11, Article 728
• Main Authors: Zeng, Lei, Tang, Zhenzhao, Chen, Pimao, Hou, Chunqiang, Chen, Guobao
• Format: Article
• Language: English
• Subjects: Acoustic surveying; Acoustics; Adaptability; Artificial reefs; Bioacoustics; Biogeosciences; Community structure; Control; Correlation analysis; Dry season; Earth and Environmental Science; Earth Sciences; Echo sounding; Echo surveys; Echoes; Echosounders; Ecosystem management; Environmental Science and Engineering; Fish; Fisheries; Fisheries management; Fisheries surveys; Fishery management; Fishery resources; Fishery surveys; Fishing; Geochemistry; Geology; Hydrology/Water Resources; Marine fish; Marine fisheries; Marine fishes; Marine resources; Migration; Original Article; Post-production processing; Rainy season; Seasons; Target strength; Terrestrial Pollution; Underwater construction; Vertical distribution; Water depth; Wet season
• ISSN: 1866-6280; 1866-6299
• DOI: 10.1007/s12665-018-7912-6

Various techniques have been used in marine fishery resources assessment. Among those, acoustic techniques have high efficiency and wide adaptability, and are environment friendly. Therefore, acoustic techniques played a key/indispensable role in the field of ecosystem-based fishery management. Acoustic surveys were conducted during the wet (May) and dry (November) seasons in 2016 in the artificial reefs ecological reserve of Bohai Gulf and a nearby control region to understand the current situation of fishery resources and explore the effectiveness of underwater artificial constructions by a dual-frequency identification sonar (DIDSON) and a scientific split-beam echosounder (120 KHz, Simrad EY60). Fish densities in various seasons and regions showed significant differences and interaction, with a maximum value of 358020.34 ind/n.mile 2 in the artificial reefs’ region and a minimum value of 71898.35 ind/n.mile 2 in the control region during the wet season. Fish densities in defined parallel transects revealed a roughly southward migration trend of small-size individuals from wet season to dry season. Single echo detections in the artificial reefs region demonstrated a wider target strength (TS) range (− 60 ~ − 30 dB vs − 60 ~ − 51 dB) and higher mean TS values (− 55.87 dB vs − 58.31 dB) than the control region both in the wet and dry seasons, which indicated a more complicated and stable fish community structure in the artificial reefs area. The vertical distribution of single echo detections tracked by the echoview post-processing system showed an apparent downward gathering effect. A positive correlation between TS and water depth was discovered from Pearson correlation analysis in the artificial reefs region during the dry season.