Three bat species are known to dine on birds. We’ve discovered this by finding feathers in their droppings. But how do these bats, which are heavier and faster than their usual insect meals, actually catch birds? That was the question a team led by biologist Elena Tena from the Doñana Biological Station in Seville, Spain, set out to answer.
Tena and her team focused on the greater noctule bat, or Nyctalus lasiopterus, the largest bat species in Europe, with a wingspan of about 45 centimeters. These bats weigh around 40 to 60 grams. Despite their size, the challenge was fitting tiny sensors to track their hunting behavior without weighing them down.
Typically, researchers might use cameras to track animal behavior. However, cameras are too heavy for the bats, especially since they hunt at night. Tena explained that any added weight should be less than 10 percent of the bat’s body weight—around four to six grams.
Over the past decade, the team tried different methods, including ground observation and military radar. Yet, observing the bats in action proved difficult. Fortunately, advancements in technology allowed for the development of lightweight sensors. Over two years, Tena’s team fitted 14 greater noctule bats with sensors weighing about four grams. These devices recorded sound, altitude, and acceleration, offering a clear picture of the bats’ behaviors during flight.
The data revealed how these bats performed quick turns and sharp dives, highlighting their agility in catching birds. The sensors captured both environmental sounds and the echolocation clicks used by the bats, shedding light on their hunting strategies. This detailed observation provided insights into their nocturnal hunts, a complex behavior that had remained largely a mystery until now.
Interestingly, this finding aligns with recent trends in wildlife research that focus on the intersection of technology and animal behavior. A 2022 survey indicated that 72% of wildlife biologists are increasingly using miniaturized tech to study species in real-time, showing a significant shift in how we understand animal interactions.
By understanding these bats better, we can appreciate the role they play in the ecosystem. Birds may seem like an unusual target for bats, but this behavior underscores the diverse hunting strategies in nature. The greater noctule bat, with its remarkable adaptations, proves that sometimes nature evolves in surprising ways to survive.
