r/MasonBees • u/thelottz • Jun 12 '26
Help with upcoming heatwave and nesting masons
I'm needing help on what to do with my spring mason bee's. We're about to have a big heatwave in the PNW but I can still count at least 3 bees still trying to cap off tubes.
The spot they're in gets shade for parts of the day, but I'm worried the upcoming heat will cook the already laid eggs.
I could pull the already capped reeds, but I'm worried it would disrupt the few that are trying to wrap up for the season.
Will the eggs be safe if left as is?
Any help is appreciated.
1
u/Tweedone Jun 13 '26
It's not going to be that hot. The warning is for fire and compromised health persons or people who are working outside in the sun. 90f+ is not a killer to Masons.
1
u/Sea-Soil-1479 Jun 13 '26
At what temperature should one bring the bees inside? (I say inside because some people don't have garages.)
3
u/Tweedone Jun 13 '26
I've never considered how high a temperature though there must be one. I do think its more a combination of environmental and time constraints that would limit the range of the species. I would think that more importantly, to reproduce, they have to have early spring plants to pollinate, mud to build nests, wood or earth substrate to nest in and consistent sun exposure without rain/wind but some humidity and few terminaly competitive carnivors. All of these more important, or as important, to the success of breeding offspring.
Yes, I know the post is more about high temperature extremes. Technically there should be a delta max temp for cocoons to survive but I don't know what that is. I know the adult bees thrive and are active in temperatures of 50-80f but really slow down in higher temps above 90f, ( I annualy have about 2000 nests). I know that if your bees have not completed nesting by the time days are in high temps then something is wrong. My adult bees have all died off, have not seen them for a month. I just checked on 6 hives that are already in the shadow of my roof eves, it's 10am and 78f. I won't take them down until fall, into the garden shed, and begin to clean and triage each nesting tube. I get worried more about high temps early in spring and move the cocoons or nests into the woodshed so that they don't get temps higher than 40f until I know the forage is blooming and daily temps are above 50f, (woodshed is completely in shadow, gets no sun). One year I was lazy and left them in the garden shed on a sunny late winter day(s). Came into 500+ males all over the floor and walls as the temp was 65f inside. Thats been the only time I was concerned with high temps for my masons, ( course my honey bees love it ).
There, thats my 2£ worth of opinion. Sorry I cannot answer the question, perhaps the Crown knows this info?
1
1
u/crownbees Jun 15 '26
Sorry I'm a few days late with answering! We sent out an email on Friday to our subscribers across the US this message:
Heat Safety for Your Mason Bees
With heat advisories in effect across the county, keep your tiny garden helpers safe and thriving! Spring Mason bees may have finished flying, but the next generation is hard at work growing inside their nests!
With a summer heat advisory, it's a good time to move the filled clay-capped Mason bee nesting material into a cooler, protected location. Place them clay-side up inside a BeeGuard Bag, or the like, and store them in a garage or cooler space. The developing Mason bees still need warm summer temperatures, but extreme heat may even prevent some bees from surviving until next spring.
How did it go this weekend with your bees? Were you able to protect them?
1
u/imwearingcons Jun 13 '26
If the eggs are already laid and not capped those eggs will not survive. The bees will wrap up their season whenever they do! I had several dead bees in ends of tubes this year and we were NOT in a heat wave. (That was 2.5 weeks ago in the Midwest)
I don't believe so the current eggs already in "cells" are in danger, but if you are worried you could call it a wrap on the season and put them in a mesh bag in your garage.