Beautiful weather year-round makes cruising the Panama Canal region relatively easy to pack for -- bring lots of sunscreen, sunglasses, a hat and a swimsuit. Casual clothing is typical cruise daytime wear and comfort is a top priority.
When selecting what footwear to take, keep in mind the shore excursions you might choose. A pair of low-heeled, rubber-soled shoes for walking on deck is a necessity; you might also consider sandals for the beach, sneakers for city tours, hiking boots for treks over uneven terrain and even flippers if you plan on spending some time snorkeling.
It's always a good idea to pack a few dressier options for nights on the ship. Many cruise lines include some formal dinners or themed events, so check with your cruise operator for details on appropriate attire.
Ports in Panama, Costa Rica, Nicaragua and elsewhere are great spots for bird-watching and other unique wildlife encounters. If creature-spotting is a hobby of yours, don't forget your binoculars and your camera -- you're sure to have some amazing photo opportunities here.