云南滇池濒危特有种滇池金线鲃繁殖初报

滇池金线鲃(Sinocyclocheilus grahami)是滇池湖泊生态系统的指示物种和特有种。因水质污染和外来物种入侵等因素的影响,该鱼类自1986年起就从湖体中消失,仅有湖周围的少数龙潭中尚保存有少量滇池金线鲃。至2007年3月初,有两次繁殖试验取得了成功。先后试验了5尾雌鱼和6尾雄鱼,获得鱼卵约1600粒,并实施干法受精。约有1320粒受精,平均受精率为73%。孵化出鱼苗约480尾,平均孵化率为36%。经10天饲养,约有95%以上的鱼苗存活,体长达8-12mm。滇池金线鲃人工繁殖成功的意义有三点:能有效保护该物种免于灭绝;繁殖的鱼苗放归湖泊合适水域,将有助于恢复滇池的土著生物多样性;有助于推动当地水产养殖业从非土著鱼类养殖向土著鱼类养殖的方向转变。

Preliminary Report on the Successful Breeding of the Endangered Fish Sinocyclocheilus grahami Endemic to Dianchi Lake

The fish Sinocyclocheilus grahami is one of the indicative and endemic species in the Dianchi Lake eco-system.As a result of pollution and invasion of exotic fishes,the fish had disappeared from Dianchi Lake since 1986 and only a few small populations survive in springs and streams around the lake.Due to the endangered status and special scientific value,S.grahami was listed as the second class protective animal of China in 1989.The importance of S.grahami and the indigenous biodiversity of Dianchi Lake were recognized by the Global Environment Foundation(GEF)/World Bank and Yunnan Development & Reform Committee.Therefore a special grant was set up to restore and conserve the indigenous biodiversity of Dianchi Lake.The artificial breeding of S.grahami is a part of the targeted activities.Two successful breeding experiments were achieved using five females plus six males up to early March 2007.Approximately 1600 eggs were collected,of which 1320 eggs fertilized using the dry-fertilizing method.The mean fertilization rate was 73%.Approximately 480 fish fry was hatched and the mean hatching rate was 36%.After 10 days of cultivation,95% fingerlings survived and their body lengths were up to 8-12 mm.The importance of the artificial breeding success of S.grahami could be summarized as following:effectively protecting the fish from extinction;releasing the fish fry back to appropriate water body of the lake could help to restore the indigenous biodiversity of Dianchi Lake;facilitating the shift of local fish cultivation from the present non-indigenous to the future indigenous fishery.