Over the past year and a half we have found these hairy caterpillar gatherings three times - always on our macaranga trees. They come together, shed their skins at least once, stay for about two weeks, then vanish.



My questions are:
What are they doing?
How do they know where to meet?
What do they turn into?
Is this an illegal gathering?

Nice picture and interesting questions - unfortunately I have no idea, but will try to locate womeone who has on return to Hong Kong. Just picked this up cruising the Highlands of Scotland - see post "big ones, old ones"

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