Cenderawasih Bay is on the northern coast of West Papua, Indonesian part of the New Guinea island. The island is divided into the west Indonesian and independent country of Papua New Guinea on the east. Cenderawasih Bay on the west side is a unique spot for close encounters with the gentle giants of the sea - whale sharks. It is a remote place but whale sharks are guaranteed, likely several at the same time, they come to you, they are close and you may be the only spectator! You can either dive or snorkel. There are several other places in the world to see whale sharks, but the experience is not quite the same. In open sea they swim past, frequently leaving you just few second for a close encounter. In more accessible places where they are fed for attraction there are crowds of people. In Cenderawasih Bay the sharks are attracted by the plankton that is attracted by the lights of the fishing platforms. The fishermen may feed them for tourists, but that is not what keeps the sharks in such numbers in the area. It is the lights of multiple fishing platforms at night that triggers plankton concentration. As the place is remote it makes more sense to combine it with diving in Raja Ampat or visiting tribes in the Baliem Valley in West Papua, or Papua New Guinea.
The whale sharks are non-migratory in the bay, so they are there all year round. However, monsoon seasons around August and December-March may lower visibility. Also, avoid the Holy month of Ramadan (April-May, dates vary annually, check online). Another factor is moonlight. There will be more sharks around the platforms at new moon, likely because the sky is dark and the light that attracts plankton at night is only at the platforms. The sharks tend to disperse in full moon. So, check lunar phases online.

You will need to fly to Nabire for the land based option. There are several Indonesian airlines that fly between the scattered islands. However, most airlines are too small to be accessible through Expedia or other regular booking sites. One need to go either to the airline sites directly or local booking services. We visited West Papua twice. First we searched on google to see what airlines fly there, then booked airfare through Ticket Indonesia and Express Air directly. The resort staff will pick you up in Nabire airport (NBX). Garuda Airlines or Lion Air (Wings Air) are larger and more reliable airlines that fly from Jakarta or Bali. There are also flights from other cities in West Papua: Sorong if you dive in Raja Ampat, or Jayapura if you visit other places such as Baliem Valley. However you may need to fly with other airlines. You will be transferred to Kali Lemon the same day if you arrive in Nabire before 11.00. It takes either 2 hours by car + 30 minutes by speedboat, or 30 min by car and 2 hours in a boat. We had the latter option but it appears they changed the logistics later. Kali Lemon is not a place you would call a hotel but it did the trick and they seem to be staying in business year after year. There may be new land-based options at the time you read this.
There are two ways to see the sharks: from a land base or from a liveaboard diving cruise. There are several companies that run this liveaboard route, usually from Manokwari. We had a good experience with Damai vessels, but there are other good Indonesian liveaboards. However, they do a limited number of Cenderawasih trips a year, mostly between June and October when weather is less favorable in Raja Ampat and other diving destinations in Indonesia. You would need to do a fresh search through the liveabord companies to see if and when they run the Manokwari-Cenderawasih route. Liveaboard option is much more organised and comfortable than the land based option, at least it was when we went there. We had to improvise because no liveaboards were available at the time we went to West Papua. Our land based adventure was through the Kali Lemon "resort". At the time we went there the place consisted of one hut suitable for tourists and a haphazard collection of service structures. It has been updated since then, but still expect very basic accommodations. When we came, they booked two couples at the same time while there was only one "tourist grade" bungalow. We, as a younger couple slept in a small room just bigger than the bed. So, when you book double check what is the current state of accommodations. If you are on a liveaboard the schedule will depend on the route. At Kali Lemon schedule is flexible. You can do two trips a day or combine an AM whale shark trip with a local reef diving in PM. The sharks come to the fishing platforms which are only 15-20 minutes away by a speed boat. The sharks circle at shallow depth and then come to the surface. You can either SCUBA dive or snorkel. If you are a diver, we recommend combining, do a couple of dives and spend some time snorkeling. Diving will give you a view from below and let you see the sharks swim by when they circle under the platform. Snorkeling will bring you closer to the sharks as they are less mobile at the surface, just watch out their tails. While diving try to keep your depth stable, especially if you are a photographer or a less experienced diver. There is no bottom to gauge the depth, it is open blue under you. It is easy to end up yo-yoing up and down which is not a good diving profile. Although at 5m it does not matter, it may matter if you start going 15 to 5 meters in cycles, down to chase a shark or sinking unintentionally and then up to correct depth or again unintentionally while holding you breath or hyperventilating. The best strategy is to go to 5m, visually memorize depth under the platform and adjust buoyancy, then pay attention to your depth and breathing
