TSU ornithologist:bioacoustics provides a clue to the secrets of birds

Sergey Gashkov, Associate Professor of the Department of Zoology of Vertebrates and Ecology of the Biological Institute of TSU and an employee of the Zoological Museum of the University, and his students are conducting research in the bioacoustics of birds using modern digital technologies in order to understand the language of birds. This is a new direction for the research of the team, and a special role here is played by the half-collared flycatcher (Ficedula hypoleuca), a species chosen as a model by ornithologists in many countries.

- The half-collared flycatcher arrives from its African wintering grounds in early May. It nests in the hollows of trees, but at the same time willingly occupies artificial nests made by people, - says Sergey Gashkov. - This feature allows us to create the desired concentration of birds by hanging out the so-called small bilberries. Such research areas are created in the University Grove, the Lagerny Garden, and also in the vicinity of the training and research station for the collective use of TSU, Polygon Kolarovo.

Over four seasons, Anastasia Bastrikova, a Master’s student in the Department, recorded the singing of single male half-collared flycatchers (90 individuals, 150 hours of recording). Analysis showed that the structure of the song in the city and in the forest areas is different. In the city, birds increased the minimum frequency of the song by an average of 270 Hz and thus avoided the constantly present low-frequency noise.

It also turned out that there are significant differences between the marriage song of young and adult males. Young individuals often perform  the same figures consistently in the song, while adults eliminate repetition, retaining the entire set of song figures, so that the singing becomes more concise. Those males no longer spend their time to attract the “second half”, but use a chosen set of “the most important words”.

The scientist also noted another interesting fact: “living space” of the birds does not influence what kind of male the female chooses. In the Lagerny Garden of Tomsk, the TSU ornithologists placed an experiment. The entrance to the house was greased with a theatrical makeup of different colors. After catching birds, it turned out that no female chose a paint of two or three colors, which means that they agreed to inspect the house “advertised” by the male after the owner's choice.

- The half-collared flycatcher is a polymorphous species, like humans, - says Sergey Gashkov. – Male birds have seven variants of coloring on the upper side of the body, from gray to monochromatic black. For example, the Tomsk population is considered light, the Moscow population has intermediate color, and the darkest populations live in Scandinavia. Our studies showed that the external differences of the males of the Tomsk population did not affect the frequency-structural characteristics of their songs.

You can listen to the song of the male flycatcher-flyer here.

The half-collared flycatcher is widely distributed in the area from the British Isles to the Yenisei. In Tomsk, the half-collared flycatcher was first noted by University zoologists only at the beginning of the 20th century. Today it is one of the common birds in the surrounding forests and city parks. The current monitoring studies of nesting biology of the Tomsk population have been going on for over 30 years.