Today, I was the first time alone at the hives since Lauri was away for a conference. I had all the equipment I needed there (apart from matches and a hive tool). It tuned out that the smoker renders useless without matches to light it. Also, opening the hive without a sharp object to be used as a lever is difficult but manageable.
Without the smoke, the bees were a bit more aggressive today, also now there is something to defend: a lot of honey and breed.
Before looking into the hive, I set up the recording equipment and captured about 45 minutes of sounds from inside the hive. There were some interesting sounds to be heard; high-pitched humming and rhythmical knocking. I am curious what this refers to.
After that, I tried something new (actually, it is a very old technique, employed at least since 70 years and described by Eddi Woods): When knocking a hive, the colony will react with a short (about 0.5 seconds long) buzz. This reaction is reported to carry information on the general feeling and behaviour of the colony as a whole; especially telling about possible preparations for swarming or queenless-ness. The Beehacker webpage has an excellent description on this. Here is what the reaction was like:
As I am repeatedly asked for the typical sound of buzzing bees, I recorded some sounds with a stereo microphone setup directly in front of the entrance.
The hive growth is truely exponential, seemingly limited by the ability to construct combs rather than by the queen to lay eggs. The three frontmost elements are the wild gown combs; note the different pattern in which the bees are crawling there.