WHAT IS VOLTINISM and What Does It Mean for Mason and Leafcutter Bees?

WHAT IS VOLTINISM?
We were on a call the other day with Abigail Lehner, a researcher and entomologist at the UC Davis Williams Bee Lab. We were chatting about her mason bee research with some of our volunteer bee hosts and the results of the Houdini Fly Hunt (stay tuned for those!), when she asked:

“Do you know what voltinism is?”

Hmmm... it sounded like something straight out of Star Trek! She laughed and explained this is a term scientists use to describe how many generations an insect has in a single year.

I grabbed my pen and said, “Wait—let me take notes so we can share this with all our followers!”

Here’s what we learned:
UNI (one) – UNIVOLTINE - One generation per year Mason bees are univoltine. They emerge in early spring, complete their life cycle once, and don’t nest again until the following year.

BI (two) – BIVOLTINE - Two generations per year Leafcutter bees can be bivoltine OR univoltine! If temperatures stay above ~70°F, their babies, will metamorphosize and grow into a full grown bee, producing a second generation... Grand-Ba-Bees!!

MULTI (many) – MULTIVOLTINE - Multiple generations per year Honeybees are multivoltine! They can produce multiple generations within a single year. In very hot climates year-round, leafcutter bees can be Multivoltine.

Quick Reference:
Mason Bees = Univoltine (one cycle in spring)
Leafcutter Bees = Bivoltine or Multivoltine (several cycles in summer if it’s warm enough)
This is why leafcutter bees can keep pollinating and filling nests through the warm months, while mason bees finish their season by early summer.

BEAM UP THE BIVOLTINE LEAFCUTTERS & SEND THEM TO YOUR HOME!
In warm climates, your leafcutter bees will BOLDLY GO WHERE NO BEE HAS GONE BEFORE! ... well not really there are bees everywhere.. but it rhymed. They'll keep pollinating and helping your garden thrive!

KNOWING YOUR BEES' VOLTINISM HELPS YOU UNDERSTAND THEIR LIFE CYCLES- AND HOW TO CARE FOR THEM SUCCESSFULLY.

Stay tuned for more insights from the bee lab soon!