Sado Wildlife in Focus | The Curious Summer Habits of Crested Ibises

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Summer has arrived in full force, and even Sado Island has not escaped the relentless heat.

Lately, I've noticed something puzzling. Even under the blazing sun, with no shade in sight, groups of crested ibises can often be seen standing on gravel roads.

These days, even many men carry parasols to shield themselves from the sun. Wouldn't the ibises be more comfortable resting in the woods, where they could escape the heat? Or along the edges of flooded rice paddies, where the water should keep the ground cooler?

Instead, they stand motionless on sun-baked gravel roads. It reminds me of walking barefoot across scorching beach sand and nearly burning my feet. The ibises, however, seem completely unfazed.

Curious, I asked Yoshinori Kaneko, a veterinarian who spent 32 years at the Sado Japanese Crested Ibis Conservation Center, what might explain this behavior.

"My guess is that an ibis's legs contain relatively few blood vessels, so heat from the ground is less likely to be transferred to the rest of its body," he said.

Why Stand Out?

That raises another question: Why do they gather on such exposed gravel roads?

Kaneko admits that "only the ibises themselves know the real answer," but he believes the height of the rice plants may offer a clue.

By this time of year, the rice has grown to about 60 centimeters (24 inches), tall enough to completely conceal an ibis. While the dense stalks make it harder for birds of prey and other predators to spot the birds, they also block the ibises' view of their surroundings. Unable to keep watch for danger, the birds may feel less secure.

Kaneko believes this may be why they gather on open gravel roads rather than along the paddy banks. The unobstructed view allows the flock to watch for predators together.

It is an impressive sight when a group of ibises blocks the road, only to be startled by something and take flight all at once.

Do Ibises Get Summer Fatigue?

In a sense, the ibises experience their own version of summer fatigue.

Their diet also changes during the summer. Loaches, their favorite food, are high in calories and can raise body temperature, so the birds begin eating more insects instead.

Even captive ibises often leave their loaches untouched during the hottest months. Caretakers reduce the amount of loach they are fed to about half their winter ration.

Unlike humans, birds cannot sweat. Instead, they cool themselves by opening their beaks and evaporating moisture from their respiratory tract, a behavior known as panting. In a previous column, I shared a video of an ibis repeatedly panting with its beak open to release excess heat.

For animals that cannot regulate their body temperature through sweating, coping with summer heat is no easy task.

Photographing in Extreme Heat

Although people can cool themselves by sweating, photographing wildlife during Japan's midsummer can still be dangerous.

To avoid disturbing the ibises, Japan's environment ministry requires photographers to observe them from inside their vehicles. The engine must also be turned off, so we can't use the air conditioner.

Within minutes, the car becomes like a sauna, creating a constant risk of heatstroke.

To avoid the worst of the heat, I usually photograph the birds between about 4:30 AM and 8:00 AM, before the sun gets too high, or from around 4:00 PM until sunset.

Even then, it's easy to lose track of time once I become absorbed in watching and photographing them. So it's not much of an exaggeration to say that I'm putting my life on the line every time I head out with my camera.

RELATED:

• Tractors Turn Rice Fields into a Bird Paradise
• Why Nearly 100 Ibises Vanished in a Year
• Crested Ibises in Mating Season

This is the 36th in the series Sado Wildlife in Focus by photojournalist Fumie Oyama.

Oyama is a two-time winner of the Japan Newspaper Publishers & Editors Association Award as a photographer for The Sankei Shimbun. After covering the reintroduction of the crested ibis to the wild for 11 years, Oyama left the company in 2020 to move to Sado Island. 

There, he continues to photograph the ibis and other wildlife while engaging in farming. He currently promotes the charms of Sado Island as a photojournalist. Follow Oyama on Instagram.

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