Years ago, I watched BBC’s Planet Earth series and was transfixed by the Caves episode.  Bats, snakes and insects make up this incredible ecosystem.  Borneo’s Mulu National Park boasts some of the world’s most impressive caves and underground passages and is featured in the BBC episode I saw.  Mysterious Mulu was beckoning me…

In Kuala Lumpur, we visited the Batu Caves, which was basically Mulu’s baby brother.  It was but a mere appetizer before the Mulu main course.    

We took a headlamp guided tour of the dark caves.  

You see centipedes, and spiders and scorpions, and worms, and cockroaches, and all sorts of creepy crawlers.  

And the whole time, you hear the chirping of bats above you.  

But, the thing is, it’s not scary.  It sounds scary, but, it’s actually quite peaceful.  

The highlight of the tour (for me): deep in the dark trenches, they ask everyone to turn their headlamps off.  We sat in the dark for a couple minutes, just listening to the chirping, the scurrying, the slithering, the whoosh of the wind and drips of water.  

Nothing living in the caves has any interest in getting near humans.  You have to trust that.  

Deep in the dark caves, there really is NO light.  You try to adjust your eyes, and still it’s complete pitch black.  In normal nighttime environments, there exists some moonlight, and or ambient light.  Not in the caves.  Pitch black.  It was INTENSE.  

Once you get out of the cave you are confronted by tons of devious monkeys that seem like they are plotting or concocting some 12 Monkeys type plan...

But, that was just the Batu Caves!  Back to Borneo...

Gunung Mulu National Park is a UNESCO World Heritage Site, protected because of its unique wildlife and plant life and protected so people of future generations can visit and experience the beauty.

Mulu was next level cave madness.  WICKED.  WEIRD.  And, MAGNIFICENT.

First, my hotel, the Mulu Marriott. It's nestled right into the rainforest.  Just listen to the awesome SOUND of the jungle.  I love that sound.  Constant buzz, chirping, yawping geckos and frogs.  So weird.

The Mulu Marriot’s mascot is the gecko (kinda).  They sell gecko stuffed animals in their hotel store. Each guest gets a gecko in their room (joke).  Here's mine:

Now, unfortunately, there was monsoon-season rain every day, and I did not get to go on the canopy walk, or the night hike, where I would have seen tons of crazy lizards, centipedes, etc.  But the real attraction was the bats in the caves.

There are 4 main “Show Caves” that most tourists visit.

Deer Cave (named because Deer used to run through the passage and lick the salt covered rocks)

Lang Cave (Gorgeous interior walls that look like jellyfish)

Clearwater Cave (because of the gorgeous river running through it)

Cave of the Winds (named because of the wind vortex that exists in some of the narrow passages. Tons of cool stalagmites and stalactites!)  

The caves are home to MILLIONS of bats.  Bats are a vital part of these ecosystems---pretty much everything revolves around them.  They eat mosquitoes and other insects.  They poop out “guano” and other insects eat the guano, and other insects eat those insects and the circle of life continues.   

I am thankful for the bats, because there’s enough mosquitoes in the rainforest already!  I’ve got the bites to prove it.  

In addition to the bats, there are Cave Swiftlets: birds that use a type of 'clicking' sonar.  The chirping of millions of bats and then the clicking of the low flying swiftlets.  INCREDIBLE.  

The clicking gets more frequent the closer they get to their target.  Click, click, click, click, click, click...like a horror movie.  

Spooky-key-kuh key, key-ku-key, key-kuh-key.

There are also millions of spiders in the caves.  They post up on the walls, and catch flies and other insects.  Check out how many webs there are:

This is a different type of web, spun by the thread worm.  It hangs and traps flying insects:

Day one of the tour ends at the Bat Observatory, outside the Deer / Lang Caves with the possibility of seeing the bats fly out of the caves in formation to feed.

Some lucky visitors get to see em.  Some don’t.  Some folks I met tried two nights in a row, and the monsoons were too strong --- no bats.  

But, wouldn’t you know it, I’m like the Lucky Charms leprechaun and even though it was raining, they came out to play.  

They come out in waves.  About 5-7 mini groups exit the cave first.  They flock in beautiful ribbon-esque formations.  After the mini groups, the rest of 'em fly out in one long ribbony stream that can last ~45 mins!  (Ours lasted about 5 minutes.  Most likely not all came out due to the drizzle of rain)  It's almost like a fireworks show with the grand finale.

Not a lot is known about bats and why they fly like this.  Bats are blind, but SHARP.  Their sonar is on point.

At my hotel the following night, I was having dessert at the pool bar, with a Dutch couple, and we realized bats were flying underneath the ceiling of the outdoor lounge and literally right over our heads.  They’ll fly so close to you and so fast, but never hit you.

My, oh, my, Mulu is magnificent!

The idea of visiting caves that are fully encrusted in bat guano may sound gross to some, but for me it was spectacular.

Seeing the bats fly out of the cave was bananas.  It was the icing on the cave cake.  

That’s it for the Borneo’s Wicked Wildlife blog series.  Borneo was one of the best travel experiences of my life because it was just so different and exotic.  Never had been to the rainforest before ('cept one day in Iguazu Falls).  But, Borneo was one week of wild and weird.  

There is a buzz in the rainforest, literally.  The sound of it is entrancing.  And, I can hear still it in my sleep.