A house centipede with joints glowing white under a black light torchlight.
The human eye cannot see ultraviolet light, but insects can.
Entomologists postulate that insects and arthropods (eight-legged creatures) use that visual ability to warn other creatures from coming near because they are venomous, or perhaps their UV markings signal their presence to their members of the opposite sex and make it easier for them to find mating partners.
Whatever nature’s reason, the world at night will appear spectacular for a hiker wielding a torchlight emitting a beam of UV light or black light.
A black light torchlight emits a purplish light, as far as the human eye is concerned, but in that spectrum is UV light that is invisible to us. And when UV light falls on some insects and arthropods, they glow conspicuously.
“Hiking in the jungle at night with a black light torchlight brings out a world that you cannot see with your own eyes,” said Rashid Shafie, naturalist and recreations manager of Rompin State Park.
An extension of Taman Negara in Pahang, covering 32,000ha of fully protected virgin tropical jungle carbon-dated to be 130 million years old, Rompin State Park boasts a well-appointed rainforest lodge with posh chalets, family lodges and dorm-style cabins, complete with plush beds, air-conditioning and various creature comforts.
So much care is given to conservation that if you choose to camp there, open fires are strictly forbidden and guests are welcome to dine in the jungle restaurant’s buffet served three times a day plus a la carte meals.
And one of the pleasant attractions is the night walk in the jungle fringes in search of nocturnal animals.
This hour-long walk starts after dinner, weather permitting, at about 8.30pm. Guests are encouraged to put on hiking shoes, trousers and insect repellent.
Your “lucky strike” will be to find venomous scorpions, brownish-black and well camouflaged in natural light, but glowing a bright turquoise blue under black light.
“Some animals can see their UV colours under natural light and it is probably a warning for other creatures because a scorpion’s sting is lethal for them,” said Rashid, stressing that while painful, scorpion venom is non-lethal to humans.
“As you walk in the jungle with black light, when you find a glowing scorpion, look closely and you will see that while the whole body of the scorpion glows, its curved sting at the tail is pitch black.
“That is very telling of how much ‘business’ is stored in the sting,” said Rashid, an ethnic Kadazan who grew up in a jungle village near Penampang, Sabah.
Even prettier is the spindly house centipede, which looks less like a typical centipede and more like a spider on steroids, with 30 long legs.
“Under black light, the joints of the legs and antennae plus its body segments will glow white-blue,” said Rashid.
There are many other insects that glow under a powerful black light torchlight. Some even glow with spots of bright pink and your chance to see them all depends on providence, serendipity or pure luck.
Rashid said the guides of Rompin State Park have black torchlights powerful enough to illuminate the myriad glowing insects up on the trees.
If you love outdoor photography and have a stash of macro lenses for super close-ups, taking photos of these insects under black light will bring you a new world of joy.
“But move slowly if you want to take good close-ups. They can sense vibrations and if startled, they will scamper away quickly,” said Rashid.
For details, visit www.rompinpark.my.