Visitors to a zoo in China were treated to an unusual sight this week as black swans lined up at the edge of a lake and fed the koi carp.
The Shanghaiist reports that, at first, the swans were not actively attempting to feed the fish, and that the behaviour is a habit that has developed over time.
The black swans are fed dry granules and they would first dip them in water to make them easier to swallow.
The site explains that the koi carp initially used to collect stray feed from the lake, but have now got so comfortable they're happy to take feed directly from the swans' mouths.
According to the Daily Mail, the scene is now a regular occurrence at Shenzhen Zoo, where the animals have lived together since 2004.
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