In a surprising and effective defensive tactic, buff-tailed bumblebees have been observed dropping out of the air “like a brick” when attacked by Asian hornets, according to scientists at the University of Exeter. The force with which they hit the ground causes the hornet to either lose its grip or allows the bee to raise its sting and ward off the attacker. This behavior, although not graceful, has proven to be successful in repelling hornet attacks. The researchers were initially amused by this technique, as bumblebees are not known for their graceful flight, but it has proven to be an effective strategy. The study also found that bumblebee colonies in areas with high numbers of Asian hornets experienced reduced growth rates, indicating the negative impact of the hornets.
Bumblebees drop from air to repel hornet attacks
Bumblebees have a unique technique to defend themselves against attacks from Asian hornets, according to scientists from the University of Exeter. While bumblebees may not be as fast or agile as hornets, they have a surprising response. When attacked, buff-tailed bumblebees simply drop out of the air “like a brick,” taking the hornet with them. The force of the impact either causes the hornet to lose its grip or allows the bee to use its stinger and repel the attacker. This technique was observed by Thomas O’Shea-Wheller and his colleagues during fieldwork in Galicia, Spain.
Buff-tailed bumblebees’ unique response
Buff-tailed bumblebees, known scientifically as Bombus terrestris, have a distinct behavior when attacked by hornets. Observations made by the research team in Galicia revealed that these bumblebees drop from the air with such force that it often disengages the hornet from their bodies. The bumblebees’ lack of gracefulness in flight actually works to their advantage in this situation. The sudden drop surprises and unbalances the hornet, forcing it to let go or allowing the bee to engage with its stinger. This tactic makes it difficult for the hornet to stay engaged and achieve its goal, leading it to disengage and move on to its next target.
Scientific observations in Galicia, Spain
The University of Exeter scientists observed the unique defense mechanism of buff-tailed bumblebees while conducting fieldwork in Galicia, Spain. They witnessed more than 120 attacks at colony entrances and found that bumblebees successfully fought off the hornets every time. This observation provided valuable insight into the effectiveness of the dropping tactic employed by the bees.
Bumblebees nest underground
One possible explanation for the buff-tailed bumblebees’ confidence in dropping from the air is their nesting behavior. These bumblebees nest underground, which may make them feel more secure heading towards the ground when attacked. If a predator tries to grab hold of them, completely bailing out and relying on gravity becomes a highly effective defense mechanism. The impact of hitting the ground with such force disorients and deters the hornet, giving the bee an opportunity to escape.
Effectiveness of dropping tactic
The dropping tactic used by buff-tailed bumblebees has proven to be highly effective against Asian hornet attacks. The observations made by the University of Exeter researchers showed that the bumblebees successfully repelled the hornets in every instance. The force of the impact and the bee’s ability to engage with its stinger made it difficult for the hornet to continue their attack. This suggests that the dropping tactic is a reliable defense mechanism for bumblebees.
Impact on bumblebee colonies and growth rates
Although the dropping tactic allows bumblebees to defend themselves against Asian hornets, the presence of these predators still has a negative impact on bumblebee colonies. The research conducted by the University of Exeter team found that colonies in areas with high numbers of Asian hornets experienced reduced growth rates. This suggests that the hornets’ presence limits the success of bumblebee colonies. While the bumblebees were able to fight off the hornets at the colony entrances, Asian hornets have been reported to prey on bumblebees elsewhere and their diet may include bumblebees as well.
Comparison to other insects’ fate
Unlike buff-tailed bumblebees, other insects such as honeybees do not have the same defense mechanism against Asian hornet attacks. When honeybees are attacked by hornets, they often suffer a grim fate. Hornets are known to decapitate honeybees quickly and process them for consumption. The observations made by the University of Exeter researchers highlight the unique ability of buff-tailed bumblebees to defend themselves effectively against these predators.
Asian Hornets’ increasing presence
Asian hornets, originally from East Asia, are becoming increasingly present in Europe and the UK. This invasive species poses a threat to native pollinators, including bumblebees. The increasing number of sightings of Asian hornets in the UK this year raises concerns about the impact on bee populations and the ecosystem as a whole.
Research findings
The research conducted by the University of Exeter team provides valuable insights into the interaction between bumblebees and Asian hornets. Over 120 attacks were witnessed, and in every instance, the bumblebees successfully fought off the hornets. However, the presence of Asian hornets still had a negative impact on bumblebee colonies, as indicated by reduced growth rates. The findings suggest that the success of bumblebee colonies may be limited by the presence of Asian hornets, highlighting the importance of understanding and addressing the challenges posed by invasive species.
In conclusion, the unique dropping tactic used by buff-tailed bumblebees to repel hornet attacks demonstrates their ability to adapt and defend themselves against predators. This defense mechanism, combined with their underground nesting behavior, gives these bumblebees a fighting chance against Asian hornets. However, the impact of the hornets on bumblebee colonies and growth rates indicates the need for further research and conservation efforts to protect these important pollinators. Understanding the interactions between bumblebees and their predators is crucial for maintaining biodiversity and the health of ecosystems.
