which ports best for water excursions?

Will be visting Port Arthur, &, Akaroa I know this may be a stupid question, but will the geology and wildlife be the same(ish) in this part of the world, or are there very different things to see on boat trips from the port??

Port Arthur offers: " a three-hour cruise along the spectacular coastline of the TasmanNational Park, between Eaglehawk Neck and Port Arthur. Experience the highest vertical sea cliffs in the southern hemisphere. Enter

sea caves; see wonderful wildlife, hundreds ofseals, migrating whales and abundant bird species in the thousands. At any time of theyear you’re likely to see the feeding frenzy of diving gannets, albatross and sea eagles wheeling on the wind, cliff-nesting peregrine falcons and playful dolphins surfing the bow wave of the boat. "

Akaroa offers this on a powered boat"

Take a chartered motor cruise on beautiful Akaroa Harbour, which was formed by a massive volcanic eruption. Cruise its deep blue waters where you will hear about the fascinating geological history of the region and its rich marine life. Among the highlights of this scenic cruise is the Cathedral Cavewith its massive sea walls that are home to many sea birds. Keep an eye out for the spotted shag and little blue penguin. While cruising towards the head of the harbor you may also see fur seals and the playful Hector’s dolphin—the smallest oceanic dolphin in the world. These beautiful marine mammals

enjoy riding the bow waves of the launch

or this on a sailing ketch:

"See the dolphins in the crater of an extinct volcano and enjoy the wildlife of Akaroa Harbour up

close. Relax and soak up the sun, sea and hills or take part as one of the crew. See Hectors

dolphins, yellow-eyed and blue penguins, New Zealand fur seals, albatross and other sea

birds. Be surrounded by giant volcanic sea cliffs, caves and rock formations along the

journey"

Can anyone tell me how they enjoyed any of the above, whether they can recommend independent tour operators offering the same kind of trip?

And, importantly, will the Tasmanian and New Zealand tours be different enough that it is worth doing both. If not, which trip has the edge?

Many thanks

Fiona