One of Nature's Greatest Spectacles

Every evening at dusk, an extraordinary natural event occurs at Niah National Park: millions of wrinkle-lipped free-tailed bats (Chaerephon plicatus) stream out of the Great Cave in a spiralling, tornado-like column that can last for 30–45 minutes. At the same time, swiftlets — which have been feeding in the surrounding forest during the day — stream inward in the opposite direction to roost for the night. The two streams weave around each other in the cave entrance without apparent collision — a phenomenon that has fascinated naturalists for generations.

When to See It

The bat exodus occurs at dusk, approximately 15–30 minutes after sunset. Exact timing varies by month with the changing sunset time. The spectacle is visible year-round, with the largest colonies present between April and September.

How to Watch

To witness the bat exodus, you must be positioned at the Great Cave entrance (West Mouth) before sunset. This means:

  • You must be an overnight visitor at Niah National Park, as the cave path closes at 5:00 PM for day visitors and the exodus begins after the standard closing time
  • Book accommodation at the park (or nearby in Batu Niah) well in advance
  • Walk to the cave (45 minutes from HQ) to arrive by 5:00 PM
  • Position yourself at the cave mouth and wait; the bat exit typically begins shortly after sunset

The Bats of Niah

Niah's cave system supports several species of bats, but the two dominant species involved in the evening exodus are:

  • Wrinkle-lipped free-tailed bat (Chaerephon plicatus): The primary species; forms the majority of the outgoing colony. Echolocates to hunt insects over the surrounding forest and agricultural land.
  • Roundleaf horseshoe bat (Hipposideros diadema): Seen in smaller numbers; a larger bat that typically emerges slightly later.

Bat Predators

The bat exodus attracts its own predators. Watch for bat hawks (Macheiramphus alcinus) — specialised raptors that hunt exclusively at dawn and dusk — making high-speed passes through the emerging bat column. Peregrine falcons are also occasionally observed during the exodus.