Nearly every Pacific country has its local airline servicing the outer islands and you'll find them all listed on South Pacific Airlines Most fly small aircraft, so only 10 kilograms free baggage may be allowed. Most runways are unlighted so few flights operate at night.
Ninety-nine percent of international travel around the South Pacific is by air. With few exceptions travel by boat is a thing of the past, and about the only regular international service left is Apia to Pago Pago. Local boats to the outer islands within a single country are available everywhere, however, and we've linked to those with websites on Inter-Island Ferries.
Many of the main South Pacific islands have highly developed bus systems serving the local people. Bus services are especially good in Fiji with all of the main centers connected by frequent services at very reasonable prices. Buses are also a good and inexpensive way to get around Tahiti, Rarotonga, Tongatapu, Tutuila, and Upolu. There's a good city bus service in Port Vila, but other than that, buses are few and far between in Vanuatu.
Because of the alternative means of travel available, the only places where you really need to consider renting a car are in New Caledonia (Grande Terre), French Polynesia, and Vanuatu (Efate), and perhaps also on Upolu in Samoa. Renting a car is an unnecessary luxury in American Samoa and Fiji due to the excellent public transportation in those countries. In the Cook Islands and Tonga one must purchase a local driver's license (international driver's license not recognized) and it's better to tour those countries by rented bicycle anyway. Bicycle is also the way to see Bora Bora.
The car rental business is very competitive and it's possible to shop around for a good deal upon arrival. Although the locally operated companies may offer cheaper rates than the international franchises, it's also true that the agents of Avis, Budget, Europcar, and Hertz are required to maintain recognized standards of service and they have regional offices where you can complain if anything goes seriously wrong. Always find out if insurance, mileage, and tax are included, and check for restrictions on where you'll be allowed to take the car. If in doubt, ask to see a copy of their standard rental contract before making reservations.
Driving is on the right (as in continental Europe and North America) in American Samoa, New Caledonia, French Polynesia, and Vanuatu, and on the left (as in Britain, New Zealand, and Japan) in the Cook Islands, Fiji, Samoa, Solomon Islands, and Tonga. If you do rent a car, remember those sudden tropical downpours and don't leave the windows open. Also avoid parking under coconut trees (a falling nut might break the window), and never go off and leave the keys in the ignition. Lock the doors as you would at home.
Bicycling in the South Pacific? Sure, why not? It's cheap, convenient, healthy, quick, environmentally sound, safe, and above all, fun. You'll be able to go where and when you please, stop easily and often to meet people and take photos, save money on taxi fares—really see the countries. Cycling every day can be fatiguing, however, so it's smart to have bicycle-touring experience beforehand. Most roads are flat along the coast, but be careful on coral roads, especially inclines: if you slip and fall you could hurt yourself badly. On the high islands interior roads tend to be very steep. Never ride your bike through mud.
You can rent bicycles on many islands. If you bring your own, a sturdy, single-speed mountain bike with wide wheels, safety chain, and good brakes might be ideal. Thick tires and a plastic liner between tube and tire will reduce punctures. Know how to fix your own bike. Take along a good repair kit (pump, puncture kit, freewheel tool, spare spokes, cables, chain links, assorted nuts and bolts, etc.) and a repair manual; bicycle shops are poor to nonexistent in the islands. Don't try riding with a backpack: sturdy, waterproof panniers (bike bags) are required; you'll also want a good lock. Refuse to lend your bike to anyone.
Most international airlines will carry a bicycle as checked luggage, usually free but sometimes at the standard overweight charge or for a flat fee. Verify the airline's policy when booking. Take off the pedals and panniers, turn the handlebars sideways and tie them down, deflate the tires, and clean off the dirt before checking in (or use a special bike-carrying bag) and arrive at the airport early. The commuter airlines usually won't accept bikes on their small planes. Interisland boats sometimes charge a token amount to carry a bike; other times it's free.
Ocean kayaking has caught on in the South Pacific, and you can rent kayaks in many resort areas. Almost every island has a sheltered lagoon ready-made for the excitement of kayak touring and you can be a real independent explorer! Many international airlines accept folding kayaks as checked baggage at no charge. Kayaking tours are usually excellent value.
If you get off the beaten track, it's possible that a local friend will offer to take you out in his outrigger canoe. Never attempt to take a dugout canoe through even light surf: you'll be swamped. Don't try to pull or lift a canoe by its outrigger--it will break. Drag the canoe by holding the solid main body. A bailer is essential equipment.