July 2019 Introduction: I remove the mesh from the top entrances of my hives as soon as I see bees crowding to push their way through the mesh. As long as the hives aren’t buried deep in snow so that shrews can walk right up to the top entrance and hop in, I don’t worry so much about mesh on the top entrance, though I do temporarily remove them in the winter on warm days when the bees are trying to get out on cleansing flights.
I used 6mm mesh (quarter-inch mesh) on my hives this winter for the first time because I lost most of my colonies last winter when shrews managed to squeeze through the half-inch mesh I kept on the bottom entrances. I’m not sure if the shrews got into the hives through the top entrances, but to be safe this winter, I covered both the top and bottom entrances with 6mm mesh. Now I’m wondering when I should remove the mesh, at least from the top entrances.
It warmed up for about two seconds earlier this afternoon and I noticed the bees going outside for cleansing flights. I also noticed them having a hard time getting through the mesh. So I temporarily removed the mesh from the top entrances to make it easier for them.
I wonder, did I really need mesh over the top entrances to begin with (especially on a tall 3-deep hives)? Can shrews climb or jump that high? I don’t know. Is it okay to remove the mesh now that we’re starting to get a whiff of some warm weather once in awhile? I don’t know. The end.
P.S.: I know this winter has been the warmest on record for the entire planet (we’re hooped). Everyone keeps telling me how it’s been a mild winter, even on the island on Newfoundland. But I don’t entirely agree with that assessment. Yes, we haven’t had much snow this year and the ponds (or what people in the rest of the world call lakes) we’re safe to walk on for maybe a few weeks. And I didn’t have a chance to go ice fishing once, which was disappointing. But as for being mild, I would say no. As a beekeeper, my criteria for mild is the frequency of cleansing flights. I would say at the most, we had maybe three days that were mild enough for the bees to get out for cleansing flights (anywhere between 5-10°C / 41-50°F). I know what it’s like when the bees get a chance to use the toilet after holding it in for several months. It’s a mess and the bees fly thick in the air. That has not happened this winter. Or at least I haven’t seen it happen, nor have I seen much evidence of it. I’ve seen the bees get out for brief periods of time, but only in small numbers because it just wasn’t warm enough. The temperatures this winter may not have been extremely cold, but most of the time, at least according to my bees, they’ve been well below 5°C, if not freezing most of the time. So that’s a NO on mild from me and my bees.
UPDATE (the next day): I just checked the weather data for my area of Newfoundland. The average temperature for February 2016 was -2°C (28°F). That’s not what I call mild. The average temperature for March last year was -5°C/23°F (it’s averaging -3.5°C so far this year). For January 2016: -4°C (24°F); December 2015: -2°C; November 2°C (36°F). Welcome to Newfoundland.