Direct impacts of commercial and recreational fishing on spiny lobster,Panulirus interruptus,populations at Santa Catalina Island,California, United States     

Matthew Iacchei  Patrick Robinson  Kathy Ann Miller 《新西兰海洋与淡水研究杂志》2013,47(6):1201-1214

The California spiny or red rock lobster, Panulirus interruptus, is an ecologically and economically important species that has been exploited since the 1800s. No previous study in California has assessed the impacts of the recreational or commercial lobster harvest. Before the 2003–04 commercial and recreational lobster seasons, we conducted a fishery‐independent trap survey at Santa Catalina Island to document the impact of the lobster fisheries on the size structure, abundance, and sex ratios of mature P. interruptus (>65 mm carapace length (CL)). We concurrently sampled a predominantly commercially fished area, a recreationally fished area, and a 23‐year‐old invertebrate no‐take (INT) reserve. Relative to the INT reserve, legal‐size lobsters in the recreational area were similar in CL, but 31% less abundant. Legal‐size lobsters in the commercial area were 8% smaller and 70% less abundant than those in the INT reserve. The sex ratio of legal‐size lobsters, although near 50:50 in the recreational and INT reserve areas, was male‐dominated (67:33) in the commercial area. Differences in CPUE and mean CL of sub‐legal lobsters in the recreational and commercial areas suggest that factors in addition to harvesting pressure may affect these populations. Total biomass of mature lobsters in the recreational and commercial areas was 92% and 45%, respectively, of biomass in the INT reserve. Fecundity in the recreational and commercial areas was 83% and 42%, respectively, of fecundity in the INT reserve. This study provides preliminary data for future ecological studies and fisheries management evaluations.  相似文献   

川西什邡地区隐伏断层活动性及其对流体的控制作用   总被引：1，自引：1，他引：0  

庞河清  王多义  蔡左花  程建  黄耀综  邓祖林  李幸运  唐蓉  蒋增平 《物探与化探》2010,34(1):14-18

利用遥感地质解译、土壤微量元素分析、土壤氡气测量以及野外露头观察等手段,在什邡湔氐地区识别出22条隐伏断层。它们按走向可分为北北西向、北东东向和近东西向3组。受关口断层推覆上升的影响,隐伏断层普遍具张扭性,活性较好,含水破碎带发育。从油气水文地球化学和地下水的活动规律来探讨该区断裂和盖层、地下水的配置关系,认为本区油气保存条件总体较差,但在单斜带局部区域寻找水动力圈闭气藏以及在云西—徐家场鼻状背斜上勘探深层气藏仍然有一定的潜力。  相似文献