It really depends on the situation. As many researchers are for coral transplanting as there are against.jonix:why bad? what happened?
I'm guessing:
* corals were cropped from other ecosystems (and more than 15% of mother coral taken) without considerations of the effects.
* corals were taken without permission or prior knowledge of the effects on new ecosystem.
* corals did not survive after transplanting due to lack of prior environmental survey data of selected site.
* corals were taken from MPA
But if the transplanted corals are thriving and the mother donor (plus it's ecosystem) has recovered, then the way I see it: no harm no foul. (oh and if it was taken from an MPA - that's pushing it!)