This time of year is extremely important for ensuring honey bee colonies are strong enough to survive winter. Understanding population size, weight required, stores, queen performance and disease status all influence a colony's ability to survive the winter. Assessing hives in the late summer and early fall allows beekeepers to make informed decisions that set colonies up for success throughout the long Maritime winter.
Colony Strength to Prepare for Overwintering Hives
It is important to assess colonies after
supers have been removed, cleaned and stored in late summer, which is when
colonies are preparing for winter. During this period, beekeepers should
evaluate disease, mite levels, queen performance, population size, and winter
stores. Colonies should be treated for Varroa mites and show no signs of Varroa
mites or symptoms of viruses, and queens should display consistent brood
patterns with healthy larvae and eggs.
A strong population is essential in the
fall. Colonies should enter winter with eight frames of bees to successfully
overwinter. To clarify, this should be
eight total frames when considering all the frames within the hive as
combined. This threshold matters because
smaller colonies struggle with thermoregulation, food access, and brood
rearing 1. A large cluster of bees maintains heat more
effectively, reaches across frames to access honey stores, and supports the
colony through long cold periods.
 |
| Fall inspections for overall colony strength and health are important (ATTTA(C)2026). |
Food stores are another critical factor,
especially in the Maritime provinces where long, cold periods prevent bees from
accessing food. Making sure there is enough honey and food stores is essential
for maintaining heat and supporting spring buildup. Colonies require 27 – 36 kg
(60-80lbs) of total honey/feed stores, including one deep full of honey
(approximately 23kg/50 lbs), and if wintering two deeps, honey must be present
in both. Colonies also require a good quantity of pollen to support early
spring brood rearing, because natural pollen does not appear until around
April. Without sufficient pollen, colonies may struggle to rear brood during
late winter and early spring, which can slow buildup and weaken the colony
heading into the new season. Supplemental feed can be provided to help colonies
survive winter. Pollen patties can support late-season brood rearing, and
fondant or 2:1 sugar syrup can be used to provide additional carbohydrates when
colonies are light.
A simple but effective way to judge winter
stores is the heft test, which involves lifting the back of the hive to
estimate weight. If the hive feels heavy and difficult to lift, the colony
likely has enough food for winter. If it feels light, additional feeding is
required. Doubles should weigh approximately 45 – 55kg (100-120lbs), and
singles should be 35 – 40kg (80-90lbs).
Preliminary winter loss data from the
Canadian Association of Professional Apiculturists highlights the importance of
ensuring colonies enter winter with adequate stores and proper strength. Early
results from the 2025-2026 season show a national loss of 34%, and in the
Maritime provinces, winter losses of 50% in Prince Edward Island, 37% in Nova
Scotia, and 27% in New Brunswick 2. These numbers do not
include confirmed causes but emphasize how vulnerable colonies can be when
entering winter without proper resources.
Written
by Kaitlyn Newton, ATTTA Seasonal Apiculturist
Connecting
with ATTTA Specialists
If
you’d like to connect with ATTTA specialists or learn more about our program,
you can:
visit
our website at https://www.perennia.ca/portfolio-items/honey-bees/
Email attta@perennia.ca
References:
1. Sammataro, D. and Avitabile, A. 2021. A
Beekeeper’s Handbook: Fifth Edition. Cornell University Press
2. Chapman et al. 2026. Preliminary Report
on Honey Bee Wintering Losses in Canada (2026).