Bumblebee count No.2

My timetable and dismal weather during my free time this week prevented me returning to the bumblebee nest until a week after my last count. Not that the weather was inviting as I began walking to the site, the dark clouds suggested rain and the strong wind was cold. Not surprisingly I saw no honeybees, hoverflies or solitary bees about. Bumblebees generally shrug off bad weather, they are tough determined little beasts.

The only other bee seen was this queen Bombus
terrestris (Buff-tailed bumblebee) feeding on
heather near to the nest.

As I approached the nest the first question in my mind was, would it still be active? No one knows with certainty how long these winter colonies last. Within a couple of minutes a bee arrived and entered the nest so I began setting up my tripod and camera to film the nest.

Filming the bees entering or leaving the nest offers a number of advantages. From the perspective of personal comfort it is preferable to watch a video in the warm than stand outside conducting the count. If my comfort is of no concern, it also offers greater accuracy as the video can be replayed and examined frame by frame. Having video also offers the possibility of recounts and the availability of other people to view it.

It had rained earlier in the morning and bumblebees have a tendency not to collect wet pollen. Out of the forty bees that returned to the nest only one carried pollen. It was debatable whether the bee had collected the pollen, it was spread on its hind legs rather than rolled into a ball as usual. It returned in the last few minutes of filming and may indicated that the flower's pollen was drying out and some stuck to the hairs on the bee's leg.

The other notable observation was that one worker exited the nest but rather than flying away, turned round and re-entered the nest - see video.

Compared to last week, there were less bees seen in a similar time span. This may be due to several possible reasons. The colony size may have decreased or possibly the bee's foraging activity may have been less due to the adverse weather, wet pollen or the difference in the time of day between the two observations.

The only certainty gained by comparing both day's counting is that more data is needed. It seems I have a new task for next week's to do list.

Bombus terrestris nest - Falmouth 3rd March 2017 11.14hrs+
P/N? = unable to distinguish whether bee had pollen due to hind legs obscured 

DUR MINS	BEES IN	BEES OUT	POLLEN	NECTAR	P/N ?	TOTAL
10	6	6	0	6	0	12
13	8	7	0	8	0	15
10	5	5	0	5	0	10
11	6	5	0	6	0	11
14	5	6	0	5	0	11
11	7	6	0	7	0	13
7	3	4	1	2	0	7
76	40	39	1	39	0	79