Lipotes usually occurs in pairs or in small loose groups. The calves are born in March-April.The Finless porpoises are usually seen in groups of five or six individuals.The blowof Lipotes lasts 0.2--0.6 sec and that o...Lipotes usually occurs in pairs or in small loose groups. The calves are born in March-April.The Finless porpoises are usually seen in groups of five or six individuals.The blowof Lipotes lasts 0.2--0.6 sec and that of Neophocaena 0.2--0.5 sec. In Lipotes,a short divewould take 10--20 sec and a long dive up to 1--2 min (average value being 31 sec). InNeophocaena a long dive would reach a maximum of 65 sec with an average of 17.5 sec.Lipotes has a pair of functional eyes. The selective secondary atrophy of a number of eyemuscles and nerves and the position of the eyes in the head correspond with the physical con-ditions of the environments so that the field of vision is directed forwards and upwards. When pursued by motor boat, both species react with a long dive and a change of direc-tion under water. With the Baiji this would occasionally cause fatal injuries by thepropeller of the ship. Such a case seems much less often with Neophocaena. The populationof Lipotes is at present very small.In the stretch of the river (between Nanjing andTaiyangzhou) under exploration, we found scarcely more than one dolphin per 4 km. Thecause for its scarcity is mostly due to accidents or wounds caused by propellers.展开更多
In springs of 1995 to 2000, plot sampling was carried out to collect information on eight habitat factors including geographic environment and human activities, etc. According to a map of navigation in middle and low ...In springs of 1995 to 2000, plot sampling was carried out to collect information on eight habitat factors including geographic environment and human activities, etc. According to a map of navigation in middle and low Yangtze River(printed in 1995), regular sampling plots, with a circular area of 500 m in diameter and with equal water and terrestrial, were set every five kilometres along the main stream, which included areas used by Yangtze finless porpoise. A total of 1 225 kilometres of survey was conducted. 247 regular sampling plots were set, of which 66 were utilized by the finless porpoises. The habitat selection of the Yangtze finless porpoises was quantitatively analyzed by Vanderploeg and Scavia selection indices. It was found that the Yangtze finless porpoises prefer cushion waters around large, gooseneck-like, bifurcated water courses, however the selection tended to be random with the decrease of flexuousity and the width to length ratio of the riverway. The feeding grounds of the Yangtze finless porpoises are usually close to sandy areas with reedy swamps where boats traveling upstream, sand excavating, and fishing activities, etc. constitute the potential threats to the finless porpoises. We suggest that the core area of the nature reserve should focus on large bifurcated riverways with cushion waters, and large areas of reedy swamps, where the sand excavating and fishing activities should be prohibited, and the speed of boats traveling upstream must be limitede.展开更多
From August 25,2006 to August 15,2007 in the open water of Tongling Freshwater Porpoise National Nature Reserve,the diurnal behavior and time budget of a pregnant Yangtze finless female porpoise(Neophocaena phocaenoid...From August 25,2006 to August 15,2007 in the open water of Tongling Freshwater Porpoise National Nature Reserve,the diurnal behavior and time budget of a pregnant Yangtze finless female porpoise(Neophocaena phocaenoides asiaeorientalis)was observed using focal-animal and continuous sampling methods.The results indicated that:1)the female predominantly invested its time in feeding(66.0±1.1%,Mean±SE),followed by traveling(11.5±0.3%),resting(10.5±0.5%),socializing(9.8±1.1%)and other(2.1±0.1%),2)among different months,it showed significant differences for each of the above behaviors except traveling,3)each of the five behaviors was significantly different among the 11 periods of the day,and 4)significant differences were observed for each of the five behaviors across the five zones of the water.展开更多
Serum transferrins(Tf)of bottlenose dolphin(Tursiops truncatus)and Yangtze finless porpoise(Neophocaena phocaenoides asiaeorientalis)were analyzed by polyacrylamide gel electrophoresis(PAGE),and the molecular weight o...Serum transferrins(Tf)of bottlenose dolphin(Tursiops truncatus)and Yangtze finless porpoise(Neophocaena phocaenoides asiaeorientalis)were analyzed by polyacrylamide gel electrophoresis(PAGE),and the molecular weight of bottlenose dolphin Tf was determined by sodium dodecylsulfate polyacrylamide gel electrophoresis(SDS-PAGE).Bottlenose dolphin Tf and Yangtze finless porpoise Tf appeared to be β-globulins.Both species have five bands even though they belong to different families,which is more bands than previously reported for some fish and terrestrial mammals.The distance between the Tf bands was gradually less from the fastest band to the slowest band.The last two bands were close to each other.However,there were no difference among the two bottlenose dolphins and three finless porpoises.Bottlenose dolphin Tf is composed of two components,whose molecular weight disparity is about 3 000 Da.The Tf molecular weights from two bottlenose dolphins were 72 700 Da/69 900 Da and 73 100 Da/69 700 Da,respectively.These values are obviously lower than those in previous studies of humans,rabbits,rats,Guinea pigs,horses,dogs,mice and cats.展开更多
文摘Lipotes usually occurs in pairs or in small loose groups. The calves are born in March-April.The Finless porpoises are usually seen in groups of five or six individuals.The blowof Lipotes lasts 0.2--0.6 sec and that of Neophocaena 0.2--0.5 sec. In Lipotes,a short divewould take 10--20 sec and a long dive up to 1--2 min (average value being 31 sec). InNeophocaena a long dive would reach a maximum of 65 sec with an average of 17.5 sec.Lipotes has a pair of functional eyes. The selective secondary atrophy of a number of eyemuscles and nerves and the position of the eyes in the head correspond with the physical con-ditions of the environments so that the field of vision is directed forwards and upwards. When pursued by motor boat, both species react with a long dive and a change of direc-tion under water. With the Baiji this would occasionally cause fatal injuries by thepropeller of the ship. Such a case seems much less often with Neophocaena. The populationof Lipotes is at present very small.In the stretch of the river (between Nanjing andTaiyangzhou) under exploration, we found scarcely more than one dolphin per 4 km. Thecause for its scarcity is mostly due to accidents or wounds caused by propellers.
文摘In springs of 1995 to 2000, plot sampling was carried out to collect information on eight habitat factors including geographic environment and human activities, etc. According to a map of navigation in middle and low Yangtze River(printed in 1995), regular sampling plots, with a circular area of 500 m in diameter and with equal water and terrestrial, were set every five kilometres along the main stream, which included areas used by Yangtze finless porpoise. A total of 1 225 kilometres of survey was conducted. 247 regular sampling plots were set, of which 66 were utilized by the finless porpoises. The habitat selection of the Yangtze finless porpoises was quantitatively analyzed by Vanderploeg and Scavia selection indices. It was found that the Yangtze finless porpoises prefer cushion waters around large, gooseneck-like, bifurcated water courses, however the selection tended to be random with the decrease of flexuousity and the width to length ratio of the riverway. The feeding grounds of the Yangtze finless porpoises are usually close to sandy areas with reedy swamps where boats traveling upstream, sand excavating, and fishing activities, etc. constitute the potential threats to the finless porpoises. We suggest that the core area of the nature reserve should focus on large bifurcated riverways with cushion waters, and large areas of reedy swamps, where the sand excavating and fishing activities should be prohibited, and the speed of boats traveling upstream must be limitede.
文摘From August 25,2006 to August 15,2007 in the open water of Tongling Freshwater Porpoise National Nature Reserve,the diurnal behavior and time budget of a pregnant Yangtze finless female porpoise(Neophocaena phocaenoides asiaeorientalis)was observed using focal-animal and continuous sampling methods.The results indicated that:1)the female predominantly invested its time in feeding(66.0±1.1%,Mean±SE),followed by traveling(11.5±0.3%),resting(10.5±0.5%),socializing(9.8±1.1%)and other(2.1±0.1%),2)among different months,it showed significant differences for each of the above behaviors except traveling,3)each of the five behaviors was significantly different among the 11 periods of the day,and 4)significant differences were observed for each of the five behaviors across the five zones of the water.
文摘Serum transferrins(Tf)of bottlenose dolphin(Tursiops truncatus)and Yangtze finless porpoise(Neophocaena phocaenoides asiaeorientalis)were analyzed by polyacrylamide gel electrophoresis(PAGE),and the molecular weight of bottlenose dolphin Tf was determined by sodium dodecylsulfate polyacrylamide gel electrophoresis(SDS-PAGE).Bottlenose dolphin Tf and Yangtze finless porpoise Tf appeared to be β-globulins.Both species have five bands even though they belong to different families,which is more bands than previously reported for some fish and terrestrial mammals.The distance between the Tf bands was gradually less from the fastest band to the slowest band.The last two bands were close to each other.However,there were no difference among the two bottlenose dolphins and three finless porpoises.Bottlenose dolphin Tf is composed of two components,whose molecular weight disparity is about 3 000 Da.The Tf molecular weights from two bottlenose dolphins were 72 700 Da/69 900 Da and 73 100 Da/69 700 Da,respectively.These values are obviously lower than those in previous studies of humans,rabbits,rats,Guinea pigs,horses,dogs,mice and cats.
