Just speculating here, but it seems like small colony general demeanor and aggressivity in locating new food sources and readiness to rear brood and expand the colony may be a genetic trait. I imagine if you had several colonies of this species, all the same size, some would be more active, and others, like this one, more passive.
I don't have much patience for passive, slow growing colonies. They generally die of neglect after a couple months in my care. Active ones will tell you what they need, while passive ones will wait for you to shove it down their throats, and then they may just spit it back out at you, almost out of spite—silly personification, but you get the point.
I think they're just massively overfed. Their gaster stripes turned from yellowish-transparent to white over the last week so I assume they fabricated a massive amount of fat reserves, probably enough to raise most of their brood even without additional resources (and they also still have half a spider in their tube).
They were quite active two or three weeks ago when I repeatedly found them foraging sugar water. But they had these periods of inactivity before - they drink sugar water in massive bursts for a few days until the entire colony is filled up and then they don't come out for a week or two. When they come out next time they'll probably gonna slurp out the entire Sunburst in the small feeder over a single night.
I've also seen them locating far away food with ease. In their old container the forager found a droplet of honey accidentally left at the container wall about 3cm above the ground and a good 20cm away from their nest entrance. They don't seem to be picky either, they've consumed basically everything I gave them so far (except the fruit flies from that really gross container) as long as they weren't overfed already.
I assume once they have more workers they'll become more active. The species itself is said to be very active with the workers exploring their surrounding for hours. And I've seen them running, they can be really really fast if they want to.
Here's one of them in the sugar water tube two weeks ago (the tube has since been replaced with a feeder as it was constantly starting to mold on the cotton after a few days):
Edited by Serafine, March 30 2017 - 1:33 PM.