The Pollinator Buzz – 1st edition, Summer 2024
Welcome to the first edition of The Pollinator Buzz! In this quarterly newsletter, we will discuss what bees are doing right now, student research, recent pollinator-related discoveries, and beyond!
The Basics
There are nearly 400 bee species recorded in Massachusetts, and the number keeps growing! These bees come in all different colors, shapes, and sizes. Unlike social honey bees and bumble bees, most of the bees in New England are solitary and live in the soil. Because bees exhibit all sorts of different behaviors and traits, there are many conservation approaches that can help preserve biodiversity in this region.
Want more information? Check out our research brief, available here.
Student Research Feature: Emelia Kusi
Emelia is a PhD student in Dr. Lynn Adler’s lab here at UMass Amherst. Emelia is investigating how floral morphology, such as flower shape, affects disease transmission in bumble bee species.
When bumble bees forage for pollen and nectar, they defecate on plants throughout their foraging bouts. Other foraging bumble bees may land on the same flower and consume the other bees’ poop. This can have consequences when it comes to pathogen transmission – but just how often is this happening, and how viable is that pathogen?
Emelia feeds bumble bees a special diet, which turns their poop fluorescent in color. This way, it is easy to see under UV light. They can then sample the fluorescent poop for pathogen viability over time.
So far, Emelia has found that broad-shaped flowers like Rudbeckia, or black-eyed Susans, have high rates of defecation. Lots of bees poop on these flowers. Due to their open shape, though, the defecation is exposed to lots of environmental factors. These include sunlight, wind, rain, and more. This exposure means that the pathogen doesn’t stay viable for very long.
On the other hand, more intricately shaped flowers have lower rates of defecation, but the pathogen stays viable for longer. When bees poop inside of one of these flowers, the defecation is less exposed to those environmental factors. For that reason, it’s possible that bees are more likely to transmit pathogens via these smaller, more intricately shaped flowers. The example species Emelia gives is Crown Vetch, or Securigera varia.
Why does this research matter?
Researchers have documented declines in bumble bee populations (Goulson et al. 2008; Cameron et al. 2011), and we know that pathogen transmission negatively impacts bumble bee health (Cameron & Sadd 2020). By understanding how pathogen transmission occurs, we can better understand the dynamics of overall bee community health.
More about Emelia!
“My favorite part of my research is that I get to work with and mentor students,” Emelia said. “My PI is awesome at giving me the opportunity to work with a lot of students.” When not actively working on her PhD, she says that sleep is usually her first choice. After resting up, she loves spending time with her friends and attending spin classes.
Citations:
Cameron, S.A., Lozier, J.D., Strange, J.P., Koch, J.B., Cordes, N., Solter, L.F., Griswold, T.L., 2011. Patterns of widespread decline in North American bumble bees. Proceedings of the National Academy of Sciences 108, 662–667. https://doi.org/10.1073/pnas.1014743108
Cameron, S.A., Sadd, B.M., 2020. Global Trends in Bumble Bee Health. Annual Review of Entomology 65, 209–232. https://doi.org/10.1146/annurev-ento-011118-111847
Goulson, D., Lye, G.C., Darvill, B., 2008. Decline and Conservation of Bumble Bees. Annual Review of Entomology 53, 191–208. https://doi.org/10.1146/annurev.ento.53.103106.093454
What are bees doing right now?
Focus: new queen bumble bees!
In early to mid-September, bee season starts to wind down. Many of our solitary bees have finished their life cycle and died, but for queen bumble bees, life is just beginning! Let’s talk about it.
Bumble bees are primitively eusocial, and their colonies may contain anywhere from dozens to hundreds of individuals. Their colonies are annual, unlike perennial honey bee colonies. Like all eusocial bees, though, the colony depends on their queen for reproduction and ultimate survival. In primitively eusocial colonies, the queen differs from her workers mainly in size. The queen is much larger than her workers. Let’s break down what a bumble bee colony might look like throughout the year:
Spring: Bumble bee queens that have survived overwintering emerge. They begin foraging for nectar and pollen and searching for nest sites. Once she is ready, the queen will begin laying fertilized eggs to produce female workers. These workers can then begin doing the foraging work.
Summer: Once there is a sufficient population of female workers, the queen never leaves the colony again. She continues laying workers, which both forage and help care for developing offspring in the colony.
Late summer: When the colony reaches a certain density, it appears to trigger the queen to start producing males and new queens, called gynes. She does this by laying unfertilized eggs. Once emerged as adults, males will spend anywhere from days to weeks in the colony as they sexually mature. Males will then depart the colony and never return. While they’re out in the world, they forage for nectar and seek out new queens from other colonies to mate with.
Fall: By the first frost, males, workers, and old queens have died. Just the newly mated queens remain, and they must forage for pollen and nectar to build up their fat stores. They seek out a place to overwinter, usually in a small nest just underground. Queens will often obscure the nest entrance with leaf litter.
How you can support queen bees & bumble bee conservation:
It’s important to have late-season flowering plants for new queen bees to forage from. The more she’s able to build up her fat stores, the more likely she is to survive and establish her own colony the following year. A great option in New England is goldenrod (Solidago sp.). These resource-rich plants bloom at the end of the season and support a wide array of pollinators, including bumble bee queens.
Leave some messy spaces in the garden! As mentioned, new queens like to obscure their overwintering nest with leaf litter. Rather than raking, leaf-blowing, or bagging it all away, leave some leaves where you can tolerate them. Queen bees also depend on some patches of bare soil where they can establish their shallow overwintering nests.
Avoid surface-level disturbances as much as possible in the winter season, particularly in these areas with some light mulch or leaf litter. There might be queen bees taking residence there!