Caving In

Sick of the beach, we decided our next visit to Borneo would be underground. The remote caves of the island’s many national parks are a spelunker’s dream—for example, the massive labyrinth of tunnels in the farflung corner of Mulu were only just discovered in the 70s and remain largely pristine, both exciting for pro cave-divers and the perfect adventure for novices like us.

To the Bat Cave!

The Mulu National Park is home to a network of caves containing many one-of-a-kind species of cave-dwellers. We hired a guide to take us to the legendary Deer Cave whose famous inhabitants—around three million bats—brought us here in the first place. Our guide, Ipoi, turned out to be the same guide who’d taken Sir David Attenborough and his BBC crew here.

Upon entering, a pungent smell attacked our nostrils, which only worsened the further in we went. It didn’t take long to figure out what it was: we were completely surrounded by bat guano. A look to the ceiling confirmed the source. Overhead, a thick black blanket of bats were dozing before their nightly feed. As night fell and the darkness outside began to match the murky interior, the exodus began. In droves, the flying rodents flew through the opening and out into the evening air, creating giant circling hurricanes with their tiny bodies, providing a form of group protection similar to pooling schools of fish. As the giant twisters grew, bat hawks swooped in, attempting to peck one off from the rapid cyclone. They continued to flow from the cave for nearly an hour, a graceful river of black darkening the dusk.

Going Deeper Underground

Feeling pretty good about our caving experience thus far, we decided to check out something a little more adventurous. Mulu is home to dozens of underground caves, including the vast Sarawak chamber, the largest underground chamber in the world and roughly the size of 23 football fields. Ipoi picked us up in a longboat outside our longhouse and we cruised along the winding water, deep into the rainforest and stopping in the middle of absolutely nowhere. We saw the large opening to our next caving conquest and felt a little relieved, as our guide had warned us of the small spaces we were going to be attempting. However, as we descended into the opening, we found that the entire inside was blocked with rock. Ipoi disappeared ahead but there didn’t seem to be any opening even from a mere foot away. Up close, a tiny slit emerged between the boulders. A quick squeeze and the rock opened up into a chamber. Then after inching though another tight space, we finally emerged into a cavernous opening under the earth. Once on the other side, Ipoi explained where the cave got its name. Racer Cave is named after the Racer snakes that inhabit the crevices in order to prey on the bats as they fly through. Sure enough the very spaces we had just slid through were lined with scaly black and white snakes, elegantly slithering along and awaiting their next meal. We delved further into the cave, climbing knotted ropes up to the higher rock faces and then down into deep, gaping caverns.

The Worm has Turned

We soon came upon a rather amazing type of worm. It has developed a remarkable defense mechanism where it leaves a brilliant phosphorous trail on your hand when you pick it up. It looks just like the worm itself and it acts as a decoy as the critter itself makes its escape. These caves here are also home to the nests made from the saliva of swiflets that are rich in nutrients and worth a fortune in China.

Ipoi pointed out a Huntsman spider just an inch away from us and bigger than our hand. He explained that these particular huntsman don’t use a web to snare their pray, but rather their impressive jumping skills and incapacitating poison. Yes, they are very dangerous to humans, especially all the way down here with no help for miles. We’d already been doing our best to avoid the scorpions covering the floor but now the walls were off limits, too. He also told us that only about 200 people had ever been in this cave since it was found in 1977 and in that time they had had to call out many rescue teams to rescue stuck cavers. Amazing as these caves are, it was around this point when we decided to complete our caving expeditions and spend the rest of our holiday above ground.