Bumblebees vs. Asian Hornets
When Asian hornets target buff-tailed bumblebees, a fierce battle unfolds in the skies. The research findings reveal two remarkable strategies employed by bumblebees:
Dropping to the Ground: When under attack, buff-tailed bumblebees display an astonishing tactic—they drop to the ground, carrying the hornets down with them. This unexpected maneuver catches the hornets off guard and disrupts their attack.
Raising Their Sting: Alternatively, the bumblebee raises its sting, prepared to defend itself vigorously. As the hornet loses its grip during the descent, the bee retaliates with determination until the hornet is forced to give up.
120 recorded attacks revealed the same outcome—victory for the bumblebees. The scientists at the University of Exeter were left "stunned" by the consistent success of the bumblebees in defending against these invasive predators.
The Threat of Asian Hornets
Asian hornets, also known as yellow-legged hornets, have already established themselves in significant parts of mainland Europe and parts of East Asia. Alarmingly, they've been recently spotted in the United States, raising concerns about their potential impact on local ecosystems. Sightings in the UK and mainland Europe are at an all-time high, igniting fears for crucial pollinators like bees.
Dr. Thomas O’Shea-Wheller at the University of Exeter explains that Asian hornets engage in a behavior known as "hawking" when attacking honey bees. They hover outside the bees' nests and intercept returning foragers in mid-flight. Surprisingly, the study revealed that the hornets attempted the same tactic against bumblebees but were entirely unsuccessful.
The Battle's Cost
While the bumblebees emerged victorious in these recorded attacks, the research emphasizes that defending against such assaults can be energetically costly for the bees. When hornet populations are high, this could become a significant challenge for bees while foraging.
Furthermore, Asian hornets not only pose a direct threat to bees through their predatory behavior but also compete with them for nectar from flowers. This competition for resources adds an additional layer of challenge for bees already struggling to survive.
The Bumblebee Research Study
The research team conducted their study in the province of Pontevedra, Spain, where they placed commercially reared colonies of buff-tailed bumblebees, Bombus terrestris, in 12 different locations. These locations had varying densities of Asian hornets, allowing the scientists to observe the bees' responses and defensive strategies.
Nature never ceases to amaze us with its incredible adaptations for survival. The revelation of bumblebees' combat skills against Asian hornets highlights the resilience of these vital pollinators. As we continue to witness the challenges facing our bees, this newfound knowledge provides hope and admiration for the ingenious ways in which they protect their colonies and contribute to the intricate web of life on our planet.
This research not only enriches our understanding of the natural world but also underscores the urgency of protecting these remarkable creatures and the ecosystems they support. It's a testament to the resilience of nature, and a reminder that even in the face of formidable challenges, life finds a way to prevail.
In addition to the University of Exeter, the research team included scientists from the University of Vigo and the University of Santiago de Compostela.
The study was funded by the Biotechnology and Biological Sciences Research Council (BBSRC) and the European Regional Development Fund (ERDF).