油茶地蜂营巢生物学观察

Observation on the nesting biology of Andrena camellia Wu (Hymenoptera: Andrenidae)

对中国南部一种独栖性蜂类--油茶地蜂Andrena camellia Wu的巢穴及其行为进行了初步研究。在对巢穴的研究中,对2省4个样地23个巢穴进行了挖掘和观察,结果显示:巢穴为无分岔的单支洞,主道在土质较好的地方倾斜角小,洞穴长度为90～150cm;在杂质多的土中,倾斜角较大,曲折,洞穴长度为30～60cm。在一定深度之下开始在主道周边出现由小径连接主道的近椭圆形虫室。虫室通常在远主道端略向下倾斜。一个巢穴中的所有虫室多在一个近似的平面上。在洞口到第一个虫室之间主道通常是近竖直的,虽然时有小的弯折;从第一个虫室向下主道往往发生一或多次偏折,但角度通常不超过45°。在对成蜂行为的观察研究中,对4头油茶地蜂连续7天的全天行为进行记录,结果显示:成蜂除雨天外均出巢采集油茶花粉;每天出巢在1～5次不等,多数为2～3次;携粉量大。

A preliminary study has been carried out on the nesting biology and behavior of a solitary bee, Andrena camellia Wu. The authors excavated 23 nests from 4 sampling sites in 2 provinces, Jiangxi and Hunan. Nests of this bee consist of main stems and branches. In some soil of high quality, the main stems are 90 - 150 cm long, with small tilt angles, whereas those in soil of poor quality are 30 - 60 cm long, with twist, turns, and big tilt angles. Under a certain depth, there are some short branches connecting the long oval cell. The cell usually slopes gently downwards. Cells of one nest nearly all stay in the same plane. From the opening of the nest to the first cell, the main tunnel is normally vertical with small turns. Downwards from the first cell the main tunnel usually has one or more turns, with the tilt angle no more than 45°. Four adult bees were observed continuously for 7 days. We found that the adult bees go out to collect Camellia pollen everyday except for some rainy days. Each bee goes out 1 to 5 times a day, and the average rate is around 2 to 3 times a day, carrying large amount of pollen.