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Two monarch butterflies, a male and a female linked together for mating, on the branch of a tree

To continue the lifecycle and produce more of their kind, monarch butterflies need to mate. The female produces the eggs inside her body, but she needs sperm from a male to fertilise them.

When the butterflies have found a partner, the male will attach the end of his abdomen to the female’s to pass his sperm to her. They will stay together for several hours, sometimes with their wings folded together, hanging from a plant, and sometimes flying from one place to another, the male carrying the female through the air.

After mating, the butterflies then fly off in separate directions. Each butterfly will usually mate again with another partner. The female is now able to lay fertilised eggs, and the cycle starts again.