4.0 Article

Development of underwater recorders to quantify predation of juvenile Chinook salmon (Oncorhynchus tshawytscha) in a river environment

期刊

FISHERY BULLETIN
卷 114, 期 2, 页码 179-185

出版社

NATL MARINE FISHERIES SERVICE SCIENTIFIC PUBL OFFICE
DOI: 10.7755/FB.114.2.5

关键词

-

资金

  1. California Department of Water Resources [46-10100]
  2. National Marine Fisheries Service

向作者/读者索取更多资源

Recent acoustic tagging of juvenile Chinook salmon (Oncorhynchus tshawytscha) in the southern portion of California's Sacramento San Joaquin Delta has revealed extremely low survival rates (<1%), possibly due to predation by piscivorous fishes. We evaluated predation as a cause of low survival by designing and testing freely floating GPS-enabled predation.-event recorders (PERs) baited with juvenile Chinook salmon. We estimated predation rates and identified predation locations within. a 1-kilometer reach of the Lower San Joaquin River. We modeled the relationship between time to predation and environmental variables with a Cox proportional hazards analysis that accounts for censored data. Our results indicated that an increase of 1 m/s in water velocity elevated the minute-by-minute hazard of predation by a factor of 9.6. Similarly, each increase in median depth decreased the predation hazard by a factor of 0.5. The mean relative predation rate in the study area was 15.3% over 9 sampling events between March and May 2014. Waterproof video cameras attached to a subset (48 of 216) of PERs successfully identified predator species 25% of the time. Our GPS-enabled PERs proved to be an inexpensive and reliable tool, which quantified predation, identified predation locations, and provided complementary information for acoustic telemetry and predator diet studies.

作者

我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。

评论

主要评分

4.0
评分不足

次要评分

新颖性
-
重要性
-
科学严谨性
-
评价这篇论文

推荐

暂无数据
暂无数据