We have been on Alaskan cruises twice. Once in early July and once in late August. We saw a lot more wildlife in late August. Because the salmon are running in August, there are more bear sightings. At the Mendenhal glacier in Juneau, there was a mother bear feeding salmon to her twins, just off one of the paths.
We also saw many whales spouting alongside the ship and even some dolphins.
Lucky you - enjoy your cruise.