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The queens of Korean native bumblebee species, Bombus ignitus were collected from the field in the spring of 1997 and reared under the various temperatures as 15℃±1℃, 20℃±1℃, 25℃ ±1℃, 30℃±1℃, 60%±5% of relative humidity and 14L : 10D, to investigate their ecological characteristics, as comparing with control(29℃±1℃, 60%±5% of relative humidity and red light). As a result, eggs were laid by foundation queen at 15℃, but they didn´t hatched out while at 20℃ eggs were laid by them and they hatched out. When a foundation queen laid eggs at 25℃ and they all were hatched out and normally grown. Finally they were developed to the normal colony. B. ignitus worker survived for 77days at 20℃, about 69days at 25℃, about 68days at 30℃ and about 63days at 29℃(control). The first brood workers emerged in 25-27days from the egg which a foundation queen laid. At the various temperatures, the captive queens stand to lay eggs in about 18days at 15℃, 15days at 20℃, 11days at 25℃, 11days at 30℃ and 4days in control. The first worker and the first drone from the egg cell of the collected queens appeared in about 27days and 72days at 20℃, 26days and 88days in 25℃, 24days and 65days at 30℃, 25days and 71days in control, respectively. In colony foundation, 33% of the collected queen at 20℃ and 25℃, 100% of the disposed queen at 30℃ and in control, and 67% of them at 30℃ and in control both produced new queens in 66days and 88days, respectively. The life span of the colony founded covered fro about 3 months at 25℃, 30℃ and in control. At lower temperatures, the life span of queen is shorter; 2 months at 15℃ and 3 months at 20℃, respectively. A colony which normally developed, varied in size with rearing temperatures; about 20heads at 20℃, 482heads at 25℃, 330heads at 30℃ and 452heads in control. A foundation queen monthly oviposited 1.5egg cells at 15℃, 3.0egg cells at 2 0℃, 21.7egg cells at 25℃, 42.3egg cells at 30℃ and 47.0egg cells in control. As a colony developed in June and July, egg cells as well as daily average cells increased in number, as compared to those in May and August. Also, in June and July, interval(days) of egg laying is shorter than in May and August. Number of nectar pots during the colony development varied with rearing temperatures; 31pots at 25℃, 39pots at 30℃, 23pots in control. The emergence of new queen showed a distinctively different two patterns; early emerging type and late emerging type. Workers are rapidly increased from early in July to early in August at 25℃, but at 30℃ and in control, emergence of workers are remarkably increased from the middle of June and last until July. No new queen emerged at 15℃, 20℃ and 25℃. New queens at 30℃ and in control emerged between late in June and early in July. Thus emergence of new queen was temperature dependent.
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