Comparison of Fitness between Captive Grus japonensis and Grus vipio in Winter in Zhalong National Nature Reserve
The present study was designed to compare the winter fitness of red-crowned crane (Grus japonensis) and white-naped crane (G.vipio) winter inhabitation in Qiqihar,Heilongjiang province,China,and to provide more reference on situ conservation.G.japonensis (5 ♀,7 ♂) and G.vipio (3 ♀,5 ♂) were housed individually in cages (6 m × 4 m × 4 m) in their natural habitat in Zhalong National Nature Reserve (123°51'-124°37'E,46°48'-47°32'N).Twenty adults were fed with the same diets and feeding method.Crucian carp (Carassius auratus) and corn were supplied regularly.During the process,G.japonensis and G.vipio were maintained in natural conditions with a short photoperiod of 9.5L∶14.5D.The body mass changes,food intake,food intake ratio,energy budget,and energy budget of unit body mass in the winter birds were compared after 4 weeks.The birds were weighed (0.01 kg) twice at the start and finish of the experiment.Ener-gy and water intake was measured for every bird.The amount of supplied and residual food was weighed daily during the experiment,and the caloric content of food intake was determined using an oxygen bomb calorimeter.The fecal discharge frequency was calculated by counting fecal deposits 5 times per day,after which the deposit was removed to ensure accurate measurement.The results showed that the body mass of G.japonensis and G.vipio were reduced 9.35％ (P ＜0.05) and 3.02％ (P ＞0.05),respectively,and food intake ratio (crucian carp/corn) were 12.70/1 and 0.93/1,respectively.No significant difference was observed in body temperature.Energy intake and the cooling energy of water discharged measured values of G.japonensis were significantly higher than G.vipio (P ＜ 0.001).However,although the energy intake of unit body mass (/kg) between the two birds was not significantly different,the cooling energy of water discharged of unit body mass in G.japonensis was significantly higher than G.vipio.In addition,due to the stress of low air temperature and short photoperiod,the food intake time of crucian carp and corn was limited only within 5.5 h and 9.5 h,respectively.These findings suggested that the energy intake demand of G.japonensis was the same as the G.vipio in winter,however,the energy budget benefits were different because of their different feeding preference.In conclusion,from the perspective of food availability and energy budget,the fitness of G.vipio should be higher than G.japonensis in winter in Zhalong National Nature Reserve.
Grus japonensisGrus vipiofitnessZhalong National Nature Reserve
NETL
NSTL
万方数据
维普
