Bumblebees can carry out dizzying maneuvers when their payload is light, but when they’re loaded up with pollen, they fly slow and steady. According to Discovery News, a new study released in the Proceedings of the National Academy of Sciences has shown how the loads bumblebees carry, either pollen or nectar, change their flight dynamics.

According to Dr. Sridhar Ravi of the aerospace engineering department at RMIT University, bumblebees can fly with over half their body mass in pollen, and nearly their whole body mass in nectar.

Bees attach nectar to their abdomen, while they keep pollen stored in their legs during flight. Ravi and his team of colleagues wanted to see how the different cargo positions affected the flight patterns of the bees, so they came up with a fascinating experiment to figure it out.

They placed trackers on 14 bees and put them in a wind tunnel with a robot flower that moved and filmed their flight performance under different conditions. The scientists measured the bees’ velocity, acceleration, and position inside the tunnel over time.

They discovered that the bees were more stable in turbulent windy conditions when they were carrying a load of pollen on their legs than when their abdomens were stocked with nectar.

On the other hand, with a steady breeze, bees were able to maneuver much more quickly and freely with a center-heavy load of nectar. The bees with nectar found it easier landing on a moving flower than the bees loaded with pollen.

The study’s findings can offer new insights into the pollinators’ behavior depending on weather patterns. For example, bumblebees might choose to gather pollen on windy or rainy days, whereas they might stock up on nectar when the whether is nice to optimize their flight performance.

With bees dying at an shocking rate throughout North America, studies like this become increasingly important. The more we know about the bees’ behaviors, the better-equipped we are to take focused actions to protect them.