Worldbuilding

I say "flying" instead of "floating" to differentiate what i'm talking about from islands that float on the sea (like Delos).

My world's flying islands are made of a kind of coral that grows up to tens of kilometers in size, usually smooth on the bottoms and with plant life on top, mostly from seeds left there by birds. The polyps excrete a gas lighter than air that keeps the colony afloat.

Islands drift with the wind and bob up and down as the coral gets dehydrated from being above the clouds and some of it dies, reducing lifting gas production and making the island sink until it becomes healthier again.

Today i wondered, what would happen if lightning struck one of these? What little i've read about lightning hitting airplanes and animals leads me to believe it wouldn't be great for the coral, but i'd love to hear what people who might know more about these things think.

Would the strike be less impactful with no ground current? Would the coral have to develop a way to avoid stormy areas? Would these things just being less conductive than air be enough to protect them, or would they need to develop something like a Faraday cage to be safe in a storm?