کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4386609 | 1304572 | 2008 | 13 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Abundance and conservation status of the Yangtze finless porpoise in the Yangtze River, China
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موضوعات مرتبط
علوم زیستی و بیوفناوری
علوم کشاورزی و بیولوژیک
بوم شناسی، تکامل، رفتار و سامانه شناسی
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: Abundance and conservation status of the Yangtze finless porpoise in the Yangtze River, China Abundance and conservation status of the Yangtze finless porpoise in the Yangtze River, China](/preview/png/4386609.png)
چکیده انگلیسی
The Yangtze finless porpoise (Neophocaena phocaenoides asiaeorientalis) is endemic to the middle and lower reaches of the Yangtze River, China. It is the only freshwater population of porpoises in the world and is currently listed as Endangered by IUCN. In November and December 2006 we used two boats and line transect methods to survey the entire current range of the population, except for two lakes (Poyang and Dongting). Sighting results were similar for both boats, so we pooled all data and analyzed them using two line transect models and a strip transect model. All models produced similar estimates of abundance (1111, 1225 and 1000). We then added independent estimates of the number of porpoises from the two lakes for a total estimate of approximately 1800 porpoises. Our findings indicate that the population continues to decline and that its distribution is becoming more fragmented. Our current estimate in the main river is slightly less than half the estimate from surveys between 1984 and 1991 (which was probably an underestimate). We also found an apparent gap in the distribution of porpoises between Yueyang and Shishou (â¼150Â km), where sightings had previously been common. Continued threats to Yangtze finless porpoises include bycatch in unregulated and unselective fishing, habitat degradation through dredging, pollution and noise, vessel strikes and water development. Immediate protective measures are urgently needed to ensure the persistence of finless porpoises in the Yangtze River. The survey design and analytical methods developed in this study might be appropriate for surveys of cetaceans in other river systems.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biological Conservation - Volume 141, Issue 12, December 2008, Pages 3006-3018
Journal: Biological Conservation - Volume 141, Issue 12, December 2008, Pages 3006-3018
نویسندگان
Xiujiang Zhao, Jay Barlow, Barbara L. Taylor, Robert L. Pitman, Kexiong Wang, Zhuo Wei, Brent S. Stewart, Samuel T. Turvey, Tomonari Akamatsu, Randall R. Reeves, Ding Wang,