found this on them
The dragonfly nymph remains in this stage from 1 to 15 years. During this time, they remain in the water and molt approximately 12 times. Upon completion of the final molt, the nymph crawls out of the water, sheds its skin, and emerges as a dragonfly. Adult dragonflies live only a few weeks to a few months
can you put it into a closed jar and find a pond or river to put it near to?