Episode Details

Spring is a season of rapid change inside the hive, and in this Bee Science segment, Dr. Dewey Caron walks through what drives colony expansion—and how beekeepers can respond effectively.

Dewey emphasizes that spring growth is fundamentally tied to pollen availability and favorable flying weather. Colonies in warmer climates may expand gradually, while northern colonies often experience a compressed and intense buildup. This variability makes local awareness and timing essential.

Nutrition plays a central role. Research going back to Heather Mattila's 2006 work shows that colonies receiving pollen or protein supplements begin brood rearing earlier and build stronger populations. More recent work reinforces that locally sourced pollen may improve effectiveness, and emerging commercial feeds are showing measurable gains in overwinter survival and pollination strength.

As colonies grow, so does the risk of swarming. Dewey underscores the importance of proactive management—providing adequate space, maintaining ventilation, and monitoring brood nest congestion. Once swarm preparation begins, options narrow quickly, making early intervention key.

The episode also introduces the "Goldilocks effect" in evaluating colony strength. Colonies that are too weak struggle to build, while overly strong colonies risk swarming. The goal is finding that "just right" balance through regular inspection, brood assessment, and strategic frame movement.

Health risks remain present during this expansion phase. Diseases like European foulbrood and chalkbrood, along with pesticide exposure and nutritional stress, can limit colony development. At the same time, brood expansion creates ideal conditions for varroa reproduction, reinforcing the need for integrated management.

Dewey's central message is clear: spring requires active, informed management—but not overmanagement. Listen to the bees, respond to conditions, and aim for balance between growth and control.

Links and references mentioned in this episode:

• Caron, Dewey M. Bee MD Bee MD [https://idtools.org/thebeemd/index.cfm?pageID=3094]

• Mattila, Hearther R. and Gard W Otis. 2006. Influence of pollen diet in spring on development of honey bee (Hymenoptera: Apidae) colonies. J. Econ Entomol. 99(3):604-13. doi: 10.1603/0022-0493-99.3.604

• Kulhanek, Kelly, et. al. 2026. Enhanced Honey Bee Colony Strength and Economic Returns from Fall and Winter Feeding with a Complete Pollen-Replacing Feed. Insects 2026, 17(3), 243; https://doi.org/10.3390/insects17030243

• Basu, Priya. 2024 Honey bee Nutrition HBHC https://honeybeehealthcoalition.org/nutritionguide/

• Tew, James. 2025. Giving it Your Best Guess. March. Bee Culture

• DeGrandi-Hoffman G, Gage SL, Corby-Harris V, Carroll M, Chambers M, Graham H, Watkins DeJong E, Hidalgo G, Calle S, Azzouz-Olden F, Meador C, Snyder L, and Ziolkowski N. 2018. Connecting the nutrient composition of seasonal pollens with changing nutritional needs of honey bee (Apis mellifera L.) colonies. J Insect Physiol.109:114-124. doi: 10.1016/j.jinsphys.2018.07.002. Epub 2018 Jul 7.PMID: 29990468

• Hoover SE, Ovinge LP, and Kearns JD. 2022.