コブハクチョウ

• The mute swan dives to a depth of up to 90 cm to forage for aquatic plants and small animals such as mollusks and water beetles.
• The mute swan has successfully established itself in North America, South Africa, Australia, and New Zealand due to human activity.
• In a 2-meter-long pool with a depth of 50 cm housing a pair of mute swans (Cygnus olor), the water must be changed every day.
• During molting, adult mute swans eat up to 4 kg of aquatic plants. This helps them regain strength and survive the winter.
• Male mute swans are heavier than females, weighing up to 8–13 kg, while females weigh 5.5–6 kg.
• The mute swan reluctantly eats dry grain, but it is essential in its diet, especially in winter. In captivity, grain must be available around the clock.