Photo/Illutration Numerous “yamame” trout swim past an underwater camera at an aquaculture pond in Akigawa Gorge in western Tokyo. (Toshiyuki Takeya)

Editor's note: This is part of a series of videos offering an up-close perspective on the animal kingdom. A special 360-degree video camera system was set up in zoos and other facilities to show how the animals view their world as they interact.

Also visit our special 360-DEGREE LIVES page (http://t.asahi.com/360lives), where you can watch all the previous videos.

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Numerous “yamame” trout swam past an underwater camera at an aquaculture pond in Akigawa Gorge in western Tokyo.

Trout Farm Akigawa in Hinohara village is home to 25,000 farmed yamame and char. The facility has an area where visitors can enjoy recreational activities at the riverside and hold barbecues. It also handles direct and wholesale sales of yamame.

During a visit in mid-October 2015, the air was chilly and pleasant with the chirping of birds and sounds of the babbling waters of Akigawa Gorge.

A video camera that can shoot at a 360-degree angle was placed at the bottom of an aquaculture pond, 60 centimeters below the surface. The pond, which measures 14 meters by 3 meters, is nurturing 8,000 yamame that hatched in December 2014.

A concrete wall that divides the pond is only 15 centimeters thick, a precarious perch for a photographer and a tripod. Kohei Nakano, 28, who manages the pond, effortlessly moves across the wall, but said he falls off the ledge and into the pond several times a year.

According to Nakano, the breeding season for yamame in the aquaculture pond comes around mid-October.

At this time of year, the mouths of the male trout become sharp and their bodies turn black. When large schools of yamame swim past the camera, viewers may be able to recognize the male fish, which are beginning to show the characteristics that mark the breeding season.