Significant population drop in South ontario
I just found out that I might have lost 3/4 of my bees comparing to one month ago. I did mite treatment in late Sep. And after that I checked the hive, it's still normal. There was a sudden temperature drop in Oct. And I began to see a lot a dead bees in front of the hive. I didn't put on the insulation because normally I did that in middle Nov. Today, I decided to put on the insulation because the temp will drop tomorrow and won't come back until next spring. But when I check the hive, I found I only have about 5 frames bees. about 1/4 of the two deep boxes.
I know the population will drop in Nov comparing to the summer. But I didn't expect this much.
Were those bees dead because of the frozen days in Oct? Can my hive still survive the winter of Canada?