猪獾种群年龄结构的研究

AGE DETERMINATION,AGE STRUCTURE IN A SAND BADGER POPULATION

本文研究了108只(52,56)猪罐头骨的生长变化规律,以矢状嵴宽度将种群划分为4个年龄组。探讨了年龄和体重、体长及头骨各部位增长的关系,以及种群数量季节变化和种群组成的相互关系。结果表明,脑颅矢状嵴宽度的缩窄与年龄增长基本一致。

The population ecology of the sand badger (Arctonyx collaris) wsa studied from May, 1984 to June, 1985 in Long County. A total of 108 specimens were obtained,am-ong which 52 were males and 56 females. Taking width of the crista sagittalis as the age criteria (Fig.l), the samples were divided into four age groups. Group 1. Juvenile: The crista sagittalis width of males and females are 30.710 ±3.650, 29.019±2.625mm respectively. The limits of thf age groups are 25.54 and 26.00mm. Group 2. subadult: The crista fagittalis width of males and females are 20.699±3.647, 19.643±3. 346mm respectively. The limits of the age groups are 15.53-25.54, 13.89-26.00mm. Group 3. Adults: The crista sagittalis width of males and females are 10.027±3.181, 8.961±2.947mm respectively. The limits of the age groups are 3.15-15.53, 5.73-13.89mm Group 4. Stnior:The crista sagittalis width of males and females are becoming 2.869±1.131, 3.005±0.846mm. The limits of the age groups are 1.74-3.15, 1.93-5.73mm. It is clear that the skull of the animal shows a considerable range of age variati-on in age groups 1-3. The hog-badger population in different age groups varies with different seasons. Peak of nubmer juvenile occurred in June, subadult in Apr., adult in Sep. and senior in May and Nov. The seasonal difference in age distribution of the hog-badger population is obv-ious.The total sex ratio is 52 males'to 56 females. There is only one litter in a year from Feb. to May.The average litter size is 4.1 young, varying from two to six.The yearling young, i.e., group 1 are usually sexually inmature; group 2 are only part'y matue;the other two groups are members in reproduction.