Photo/Illutration The northern goshawk (photo by Emiko Kato, provided by the Chiba prefectural government)

The northern goshawk, a favorite of bird watchers in Japan, always cuts a fine figure whether in flight with its wings spread or at rest in a tree.

There was a time when urban development and overhunting nearly drove these birds to extinction, but their population has since rebounded, and they have recently started appearing in cities.

It is their peak fledging season in central Tokyo.

To protect them, most of their breeding locations are not disclosed to the public. But some are disclosed because the nests are inaccessible to humans.

One such location is the Institute for Nature Study, a nature preserve park associated with the National Museum of Nature and Science.

Observations have continued since breeding was confirmed there six years ago. This year, the entire brood of fledglings--four in all--successfully left the nest for the first time.

Takumi Endo, 34, a staffer at the institute, said he is most anxious during the nest-building season.

The goshawk is in the habit of using the same nest every season, but crows sometimes destroy it. And this year, a masked palm civet was found to have profusely defecated in last year’s nest.

However, the goshawk couple returned to the defiled nest, covered up the feces with branches and leaves and started laying eggs in late March.

Endo didn’t let his guard down even after the eggs had been laid, however. One year, a nest was attacked by an “aodaisho” (Japanese grass snake) as well as by a masked palm civet.

The latest “enemy” is sudden torrential rain. Last year, a downpour killed a chick that had just hatched.

“When heavy rain falls before a chick has grown its feathers, its parents can’t save it even if they cover it with their bodies,” said ornithologist Hiroyoshi Higuchi, a professor emeritus at the University of Tokyo. “Unlike unacceptable human behavior such as reckless picture taking, deforestation and poaching, there is nothing you can do to stop torrential rains.”

Goshawk eggs hatch before the start of the “tsuyu” rainy season, but perhaps heavy rains have become more frequent.

The main reason we can see goshawks in central Tokyo is said to be that the city’s crow population has declined, which, in turn, has helped repopulate pigeons and starlings on which the goshawks feed.

Upon learning that the fledglings remain in the nature preserve park for about a month after leaving the nest, I strained my ears, hoping to hear them.

--The Asahi Shimbun, June 27

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Vox Populi, Vox Dei is a popular daily column that takes up a wide range of topics, including culture, arts and social trends and developments. Written by veteran Asahi Shimbun writers, the column provides useful perspectives on and insights into contemporary Japan and its culture.