Bats eating birds trapped in the air

2001/08/07 Astobiza, Amaia

• Biologia
• Zoologia

As is known, bats are insectivorous or flowers/fruits. However, some species living mainly in the tropics also capture birds that do not fly. However, according to the study conducted by the team led by Carlos Ibáñez, the great night bats (Nyctalus lasiopeterus) are captured by small migratory birds in flight. The news is very curious, since the experts believed that birds in the air were only hunted by birds of prey.

During the last two years, scientists from the Biological Station of Doñana and the University of Alcalá de Henares have been studying the great nocturnal bat that lives in the mountains of La Rioja and in the park of María Luisa of Seville, finding evidence that they also eat birds. On the one hand, in the nests and feces of the night bats, feathers and other remains of birds have been found. On the other hand, the frequencies of the ultrasonic noises that occur during hunting, as well as the current flight, have been analyzed.

In total, about 14,000 samples were analyzed and in the autumn migration period, the presence of bird feathers was detected in 70% of the samples. Bats usually hunt only at night, while most of the small migratory birds rest only during the day. Taking into account these two factors, experts believe that bats capture birds at night. In addition, membranes in the form of bat and low-frequency sounds are more suitable for outdoor hunting than for small trees.

The night bat is the largest bat in Europe, with open arms can reach a meter wide. It has brown fur and, if it lives in a non-tropical climate, it spends the winter hibernating on the trunks of the trees because there are no insects and has no food. It lives mainly in southern Europe (Spain and Italy) and in Asia.

The next work of scientists is to analyze the DNA of the feces to identify the species of birds preferred by bats. In addition, they want to use the high definition radar system of the Spanish army to be able to see live bird hunting.