A schoolboy has admitted to tormenting a black swan with an electronic cigarette in a case of animal cruelty that has shocked the community.

The bird was gripped around the head and the beak and forced to inhale smoke from the battery-powered device, commonly known as a vape.

WATCH THE VIDEO ABOVE: Schoolboys charged over black swan vaping incident

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The Mandurah Children’s Court was told it happened in an inflatable boat near Dawesville, south of Perth, at the end of July.

The boy appeared before a magistrate on Monday where he pleaded guilty to animal cruelty — causing an animal unnecessary harm.

His lawyer claimed he noticed the swan had a fishing lure in its neck, and that he removed it and put the animal, an official bird emblem of WA, back in the water.

A distressing 10-second clip of the incident that has been widely circulated online does not show the release.

The Magistrate was damning, saying “it’s like treating a young child in a cruel way” and telling the boy he had participated in a “serious offence”.

He had nothing to say as he left court.

Two boys have appeared in court accused of animal cruelty against a black swan south of Perth. Credit: Supplied courtesy of The West Australia

Police allege he did not act alone and have charged another, older boy.

The court was told that boy slapped the swan with his hand and recorded the encounter on his mobile phone.

The second child was also in the same children’s court on Monday but did not enter a plea.

The pair, who cannot be identified because they are under 18, will appear in court again in September.

They are not allowed to contact each other in the meantime.