标记重捕技术对湖北钉螺滇川亚种在湖沼水网地区种群动态的实验研究

Population dynamics of Oncomelania hupensis robertsoni in lake marshland and water network regions by mark-recapture method

目的观察湖沼水网地区外来输入性湖北钉螺滇川亚种的种群动态。方法于2009年10月-2011年4月,在湖北省江陵县血吸虫病疫区的有螺环境构建实验现场,将异地采集的湖北钉螺滇川亚种采取野外放养的方式,定期查螺,通过标记重捕技术方法对输入性湖北钉螺滇川亚种的种群进行估测。结果湖北钉螺滇川亚种丹棱株从2009年10月引入湖沼水网地区经过6个月生存后,至2010年4月预测钉螺种群数有1 501.88±134.38只,进入钉螺的繁殖季节后,钉螺通过繁殖形成新老交替,于2010年7月查获的钉螺多数为当年子代钉螺,预测钉螺种群数达到1 587.17±429.09只。然而,随着观察时间的延续,2010年10月预测钉螺种群数仅210.34±151.69只。彭山株钉螺经过一个繁殖季节,2010年7月预测钉螺种群数分别为1112.63±292.48只,至2010年10月,预测彭山株钉螺种群数为1 12.23±107.54只。通过湖北钉螺滇川亚种理论标记的钉螺在种群中的总数Mx和实际标记释放总数qx配对t检验,显示差异无统计学意义,实验结果与理论值吻合较好。结论外来湖北钉螺滇川亚种输入至湖沼水网地区后短期内其种群数量呈现由多到少的趋势。

To observe the survival of imported Oncomelania hupensis robertsoni in lake marshland and water network re gions, a pilot study was established in a snail habitat and schistosomiasis epidemic areas in Jangling County, Hubei Province between October 2009 and April 2011. The O. h. robert＇soni in field experiment were collected and identified, and then put into the wild after properly marking. The survival rate was checked in predetermined time intervals, and the number of imported O. h. robertsoni was estimated by mark-recapture method. The results showed that the estimated number of survival O. h. robertsoni Danling strains was1501.88±134.38 after 6 months （Oct 2009-Apr 2010）. After breeding season （July 2010）, most O. h. robertsoni were from the original group, with an estimated number of 1 587.17±429.09. However, the number dropped to 210.34±151.69 in Oct 2010. The estimated number of Pengshan strains was 1 112.63±292.48 after breeding seasons （July 2010）, and dropped to 112.23±107.54 in Oct 2010. Results suggested that the precision of test （P）0.05） and theory marked results were consistent. It is indicated that species population of imported O. h. robertsoni decreases during a short period oftime after moving to lake marshland and water network regions.