During the winter in CT you don't generally get alot of days where you would really want to open up the hives due to the cold. The occasional warm 50 degree days are usually accompanied by wet weather. Anyway, I noticed alot of dead bees on the bottom board in 1 of the hives about a week ago and was concerned. I tapped on the side, no noise and did peak inside the top and found nothing in the top deep. This hive went into the winter taking in alot of 1:1 sugar syrup and the population was very good into November. Although this was a new package in the spring, I thought we were going into the winter pretty strong. Other than opening up the hive and disturbing them, are there other less invasive ways to check on this hive?