防城港人工礁区内5种恋礁鱼类的声学标志跟踪

为了解人工鱼礁区鱼类的活动特点及使用超声波遥测方法进行人工鱼礁区鱼类研究的可行性, 2017年7月7日至9月8日于防城港人工鱼礁区利用Vemco定位系统(Vemco position system, VPS)对5种北部湾沿海常见的野生恋礁性鱼类共9尾体长(21.7±3.8) cm,体重(314±186) g]进行超声波标志遥测跟踪。结果表明, 9尾鱼中的3尾定位效果较为理想(1749～9591个定位结果),活动范围较小,其中100%最小凸多边形(minimum convex polygon, MCPs)范围为12687.6～17123.2 m^2。而50%和95%核心利用分布(Kernelutilizationdistribution,KUDs)范围为5788.1～8708.9 m^2和10240.5～16463.7 m^2。另6尾鱼未取得理想的定位效果(0～14个定位结果),接收机接收回的定位数据可以被检测,表明鱼依然在礁区附近活动。在游离检测范围28～51 d后又有信号返回,说明样本鱼对人工鱼礁环境有一定的偏好性,研究期间样本鱼表现出一定的活动深度变化规律,在15:00～22:00时段活动深度相对较浅,主要集中于人工鱼礁礁体上方(距水底5 m以上)。研究表明,应用超声波遥测技术可以了解鱼类在自然生活状态下的活动特点,可作为鱼类研究的有效手段加以应用。

Exploration of 5 species of rock fishes in the Fangchenggang artificial reef area using ultrasonic biotelemetry

To understand the attractive effect of artificial reefs, the activity traits of fishes, and the feasibility of ultrasonic telemetry for fish research in artificial reef areas, 5 species of 9 common rock fishes (22.0 cm±3.5 cm; 314 g±186 g) in the Beibu Gulf were tagged and tracked within an artificial reef area between July 7 and September 8, 2017, using the Vemco position system(VPS). Eleven receivers (VR2Tx, Vemco, 69 kHz) were launched in the artificial reef area of Fangchenggang inshore and the transmitters (V9P-2x, Vemco, 69 kHz) were tied to the backs of fishes. Not all fishes had good position results, and only 3 fishes had data available for analysis of home range size using 95% minimum convex polygons (MCPs). Home ranges were between 12687.6 m² and 17123.2 m², and the MCPs showed the activity of fishes in the small ranges. The other 6 fishes had poor position results (between 0 and 14 locations), and although the signal could not be received by 3 or more receivers, the data still indicated that the fishes were moving near the reef area because the range of signal reception was only approximately 200 m in the artificial reef area. Three fishes with poor position results left the area during this study between 28 to 51 days and then retured. This indicated that the fishes preferred the environment of the artificial reef area. During the study, the activity of fishes showed certain depth change rules. The fish activity in the shallower layer was between 15:00-22:00, and fish activity occurred above the reefs during this time, and perhaps it is the optimum time frame to determine the quantity of resources of these fish species in this area. To ensure the accuracy of the results, we eliminated the effect of tide before the calculation of depth results. The method of ultrasonic biotelemetry has an intuitive feeling for fish activity, but the method is in an experimental stage in China. The high cost is one reason why it cannot be widely promoted; furthermore, in the current experiment it was difficult to achieve the desired effects. We hope to analyze effectiveness for fish attraction and daily activities of fishes to provide a reference for subsequent research, and accumulate experience for subsequent application of this method.