Do I need to bring anything special?

Nothing more than a warm jacket in winter, and whatever else you might like to have. Don't forget your camera!
Tromsø: Warm and comfortable clothing for being outdoors in the Polar winter and wind. We do have a few thermal winter suits hanging on the boat to borrow but there are not enough for all guests, so we recommend coming in your own winter gear. The boats lounge area is heated. 

If you are planning a hike or excursion off the boat, you need to brings things like hiking boots, food and drinks for use after disembarking.