福建沿海文昌鱼的分布及其资源保护对策

Lancelet distribution in Fujian sea waters and its protection strategy

采用现场采样方法对福建沿海文昌鱼(Branchiostoma balcheri)的分布和资源状况进行了调查,为文昌鱼的保护提供依据。全省19个海区潮间带均未捕获文昌鱼;12个海区的潮下带浅海定量调查中,仅5个海区采集到文昌鱼。东山湾海区文昌鱼密度最高,为41.67尾/m2,其次是厦门十八线海区,为14.5尾/m2,厦门南线海区和黄厝海区分别为5.39尾/m2和4.71尾/m2,泉州大港海区仅捕到1尾,闽江口3个海区均未捕获。所获文昌鱼年龄大多为1龄,占39.2%,2龄占23.5%,3龄占25.5%,其他(1龄以下、4龄、5龄及以上)占11.8%。与20多年前的历史资料相比,文昌鱼的分布区大为缩小,资源量大为降低,资源已濒临枯竭。必须加大对文昌鱼资源的保护力度,有必要增设文昌鱼自然保护区,并加强对文昌鱼保护区的管理。

The resources and distribution of lancelet were investigated by field sampling along the coast of Fujian Province, at low, middle tidal zones and areas below the tidal zone. No lancelets were found in all 19 sites across the low and middle tidal zones. Lancelets were obtained in five of 12 investigated locations below the tidal zone with the highest density （41.67 individuals / m^2） in the Dongshan Bay, followed by the Shibaxian sea area in Xiamen （14.5 individuals/ m^2）, the Nanxian sea area and Huangcuo sea area in Xiamen （5.39 individuals / m^2 and 4.71 individuals / m^2, respectively）; only one sample was caught in the Dagang sea water of Quanzhou; and no lancelets were obtained in the three stations of the Minjiang River Estuary. The age distribution was as the following： the largest numbers of lancelet, accounting for 39.2%, were in age Ⅰ, 23.5% in age Ⅱ, and 25.5% in age Ⅲ; and others （under age Ⅰ, above age Ⅳ and age Ⅴ） accounted for only 11.8% of the samples. Compared to the historical data 20 years ago, the abundance of laneelet has experienced dramatic declines, its distribution has reduced sharply, and the resources of this species are at the verge of depletion. It is necessary to establish lancelet natural reserves and strengthen the management.