Kaimana Whale sharks

Near the town of Kaimana in West Papua, Indonesia are several large bays. They are plankton and fish rich. It is there that you find many Bagans.

Bagans are large floating fishing platforms made out of bamboo and wood. Fishing is done only at night. That is when large nets are lowered into the sea and strong lanterns are placed around the perimeter of the bagans. This attracts large schools of baitfish.

The Whale sharks usually congregate around these Bagans in the morning looking for leftovers of last night’s catch and an easy meal. Partially a preventive measure to avoid the filching of nets, the fishermen usually hand out some fish to them. It is also said that they bring luck to the fisherman. Whale sharks also use their powerful mouths to suck bait from the holes in the nets, hovering just beneath the surface of the water.

Rather uniquely when compared to other known Whale shark aggregations, the Whale sharks of the Bird’s Head area of Indonesia appear to be present year round. In most other areas of the world, Whale sharks are observed only seasonally.

Given the year-round abundance of baitfish in coastal areas such as Cendrawasih and Triton Bays, this makes sense – why go on long migrations if you have a plentiful food source available all the time.

The Whale shark is the largest known fish species growing to 18 meters long. Females are larger than males. They feed almost exclusively on plankton and small fishes, and pose no threat to humans. Whale shark mouths can contain over 300 rows of tiny teeth and 20 filter pads which it uses to filter feed. At birth it is estimated that they are only 40 cm long.

Despite being the world’s largest fish, we do not know that much about Whale sharks. There is currently no robust estimate of the global whale shark population. Nearly all of the known aggregations where tourists regularly interact with whale sharks (including the Bird’s Head area) are comprised nearly exclusively of juvenile to young adult males in the 3-8m size range. Young whale sharks in the 60cm-2m size class are almost never seen, nor are females in general – and the large adults are only rarely encountered in certain areas like the Galapagos. We can only assume the females and young and adult males are spending their time at depth, though no one knows for sure.