I suggest you read the ports of call section on Dominican Republic on cruise critics. From what people say it is not worth getting off the ship! Oops.
We did the whale watching trip last Feb from Samana using a local firm and to be honest it was a bit of a disaster. The sea was a bit choppy, the boat too small and the whales didn't want to play. We got absolutely soaked, as did the camera, and had a couple of brief glimpses of these beautiful creatures in nearly two hours of bouncing up and down. Others have been luckier and may be you will be! You get what you pay for.
Thank you for this review. We too are taking the Jewel in February and Samana is one of our ports. I did some reading about this stop and it is a newly declared island. Our experience with past sailings and (New Islands)it wasn't worth getting off the ship. I'll report back in two weeks.
Janna, California on 24th Feb 200.