A active colony of Paper Wasp (Polistes sagittarius) was recently located inside a drainage hole of about 40 cm running through the retaining wall of my neighbour’s house (above). There were 3 nests inside. The deepest and oldest nest was about 10 cm from the entrance and usually not visible. The other two nests were by the entrance, with the more recent nest in front (see video below).
A number of wasps were always loitering around the opening, no doubt guarding the colony. At times one flew off or another flew in. And at regular intervals a wasp was seen emerging with a whitish morsel in its mouth to immediately gobble it up (see video above). At 2:15 min. of the video, a large, possibly inedible object was brought out by a wasp and flown away, most likely for disposal (see also screen-grab below). Obviously the wasps were also house cleaning.
At 5:20 min. of the video a wasp was seen regurgitating a drop of liquid at the entrance, followed by two droplets between 5:45-5:50 min. (see also screen-grab below). According to Dr Leong Tzi Ming: “The regurgitation of the water droplets seems to be a conscious removal of water from within. There may have been some internal seepage due to the recent rains, so the wasps were keeping their home dry. Bees and wasps can be very particular about temperature and humidity of their homes.”
A few days after the video was completed, the owner of the house sprayed insecticide to chase away the wasps. After all, the wasps did sting a few inquisitive pedestrians who disturbed the colony.
YC Wee & Dr Leong Tzi Ming
16th July 2016