Scientists study bee reproduction to strengthen colonies

One‑third of the food Americans eat depends on a tiny worker most people rarely think about – the honeybee – but across the U.S., beekeepers have seen honeybee colonies collapse at alarming rates.

Now, a team of Texas A&M AgriLife Research scientists is looking inside the hive for answers. A new research effort is exploring how the reproductive health of honeybee queens and their mates – or drones – shape and strengthen the survival of colonies.

The AgriLife Research team will look at parasites, disease and environmental stressors like weather and chemicals which are putting growing pressure on the important pollinators supporting a significant share of the nation’s food supply.

Dr. Juliana Rangel, AgriLife Research entomologist and professor of apiculture in Texas A&M Universityʼs Department of Entomology in the College of Agriculture and Life Sciences, leads the new five‑year, U.S. Department of Agriculture-funded project named Sustainable Ways to Advance Reproductive Management in Honeybees (SWARM).

The project brings together researchers across disciplines and continents to better understand how environmental stress affects the way queens and drones grow, mate and ultimately keep colonies healthy.

“This couldn’t have come at a timelier moment because of issues with high colony losses,” Rangel said. “If we can help improve the reproductive health of the queens that head these colonies, then we can help improve colony health, productivity and sustainability.”

Rangel is joined on the project by department colleague and Assistant Professor Dr. Erick Motta, an AgriLife Research scientist whose research focuses on microbial communities and their dynamic relationships across ecological and agricultural systems, and Dr. Nancy Ing, AgriLife Research scientist and professor in the Departments of Animal Science and Veterinary Integrative Biosciences, whose expertise includes genetics and reproductive biology.

International collaboration 

The project also includes collaborators in Northern Ireland and the Republic of Ireland, where scientists face other environmental challenges affecting bee reproduction.

Rangel and her team are partnering with Irish colleagues to identify reproductive characteristics in the Irish bee population which could help colonies in the U.S. remain more resilient under environmental stress.

A honeybee colony depends on one queen, which mates with 12 to 15 drones during brief, risky flights early in her life. 

According to Rangel, the number of drones she mates with, the quality of their sperm and the viability of what she stores in her reproductive organ – known as a spermatheca – determine how long she can sustain the colony.

But, environmental pre-
ssures can disrupt this delicate process.

In Texas, Rangel said obstacles often include high pathogen levels in developing colonies, nutritional stress and pesticide residues in the nectar and pollen bees forage. 

The team will examine how each of these factors affects both queens and drones – from nuptial flight behavior to sperm count and viability.

In Ireland, honeybees face a different challenge. Queens have a very short mating season due to frequent rain, which limits the opportunity for mating flights. The short window and challenging conditions decrease the likelihood queens will travel far, often leading to inbreeding, which weakens colonies over time.

New tools and practical solutions 

Beyond advancing scientific understanding, Rangel believes the project could provide practical applied science and tools for beekeepers.

One of the project’s most groundbreaking components is the search for molecular marker RNAs inside queen-laid eggs. These tiny biological signatures could allow beekeepers to assess queen fertility without harming her. 

A reliable queen fertility test would be a significant advancement for beekeepers, Rangel said.

This project also includes an outreach component. Texas A&M AgriLife Extension Service specialists will develop beekeeper surveys, expand queen‑rearing workshops and deliver new training in Texas and Ireland based on research findings.

“The goal is to continue improving the reproductive health of queens and drones,” Rangel said. “Healthier queens mean healthier colonies, and this strengthens the pollination systems which our food supply depends on.”

Adam Russell is a communications specialist for Texas A&M AgriLife. This article was originally published by AgriLifeToday on April 10.