The Bull-headed Shrike, a lovable carnivorous bird
Being a carnivorous songbird is unusual enough, but there's plenty more to discover about this social, competitive bird and the true reason behind its macabre method of storing prey. From "Through the Lens”, Fujingaho Magazine, December, 2020.
'Through the Lens', Fujingaho Magazine, December, 2020
Photos and text: Her Imperial Highness Princess Takamado
English Translation: Asia Club, a WBSJ Volunteer Group (YOKOYAMA Kazuko, KASE Tomoko, Ueno Naohiro)
It seems that the season of autumnal foliage arrives rather late these years. While in my memory of childhood, we used to enjoy colored leaves from October through to November, recently trees on flatlands do not change their color until December. So this month I would like to show you some photos of the Bull-headed Shrike Lanius bucephalus, one of the typical birds of autumn.
The Bull-headed Shrike is a carnivorous songbird that lives in open habitats, such as river beds and farmlands, feeding on insects, amphibians, reptiles and small mammals; anything living close to the ground. Its beady eyes are really cute, but a closer look at the bird tells you that its beak is the same shape as a raptor's. That is why in Japan it is nicknamed as “Mozu-Taka”, Mozu being the Japanese name of the Bull-headed Shrike, and “Taka”, the generic name for larger birds of prey. The Bull-headed Shrike is a resident bird in many areas where it is commonly seen and familiar to local people.
One of the bird’s most commonly-observed features is its harsh, grating call. Every year, towards the beginning of October, when autumn colours begin to prevail, it calls loudly, declaring its territory. And since not only residents, but also migrants and even recently-fledged juveniles display territorial behavior, the scene is quite bustling as the birds rearrange their territories. Uniquely enough, male birds also claim territory in winter, so it is highly likely that you will happen upon this species at this time of year.
Another interesting feature is a behavior called “Hayanie” in Japanese, which is seen from autumn through winter. The bird impales some of its prey upon the pointed tips of branches or the thorns of trees, as well as on barbed wires within its territory to create “Hayanie”, meaning quickly-prepared prey. This behavior is observed in other birds too, and has been considered a “food-cache behavior” to stock prey carefully.
However, last year, interesting findings were published by Dr. NISHIDA Yusuke, the Specially Appointed Lecturer of Osaka City University, et al. According to their research, it was found that male Bull-headed Shrikes make “Hayanie” only in non-breeding seasons, and eat almost all of it before the breeding season arrives. The more “Hayanie” a male bird makes and eats, the more quickly and beautifully it can sing in courtship displays, and as a result achieves higher popularity among females, ending up in earlier pairing. In other words, it has been made clear that for a male Bull-headed Shrike, “Hayanie” is not only a food cache, but also nutrition to upgrade its song.
An enormous number of creatures alive on earth have social, as well as biological, adaptations. Because they are so numerous, new findings must be appearing almost every day. As a matter of fact, I make a habit of taking some time to indulge in the joy of obtaining the most up-to-date knowledge, by reading research papers based on many years of study and hard work by the scholars and specialists.
This year, we learned a lot of things related to COVID-19. As far as COVID-19 is concerned, discovery, study, evolution and adaptation are things we will all need to keep doing for some time. It is no longer someone else’s affair. I would like to refrain from making irresponsible comments on any new findings. Instead, by accepting and considering with sincerity, I will try to widen my own knowledge and make best use of it in my activities from now on.