I have built an observation hive to take to local farmers artisan market. it is an ulster type built on a 5 frame bottom box and two frames above under Plexiglas.
I have 3 fames below and a feeder. I cut a queen excluder to fit and place queen upstairs under the Plexiglas. this morning I noticed worker bees pulling out larvae. there doesn't appear to be anything wrong with the larvae, no visible mites. I have air holes along top of hive and along the top of the glass. also a screened bottom. Are they just stressed being closed up, or not enough ventilation. or is something going on with larvae.