Spiders and Insects in Bali: What's Harmless and What Hurts

Are there dangerous spiders and insects in Bali?

Not in the way most people fear. Bali has some impressively large spiders and plenty of creepy-crawlies, but none of the island's common spiders are considered a serious danger to people. The bites and stings that actually hurt here come from centipedes, scorpions, ants and wasps, and they are painful rather than life-threatening for healthy adults. The insect that matters most for your health is the mosquito, which we cover in our separate guide to mosquitoes and dengue in Bali.

The tropics simply mean more life, indoors and out. A gecko on the ceiling or a beetle by the pool is normal, not a sign of a dirty villa.

The big spiders that look worse than they are

• Huntsman spiders: The famous one. A flat, fast, leggy spider that can span the size of a hand and likes walls, ceilings and the backs of curtains at night. It is not aggressive and eats cockroaches and other insects. A huntsman will bite if trapped against skin, which is painful but not dangerous. If one bothers you, trap it under a container, slide a card underneath and release it outside.
• Golden orb weavers: The giant spiders with golden webs strung between trees and power lines, especially in the hills and rice-field country. Videos of them in the north of the island go viral every so often. They stay in their webs and are harmless unless handled.
• Jumping spiders and house spiders: Small, common and useful, since they eat mosquitoes and flies.

You may read about tarantulas in Bali. Ground-dwelling tarantula-type spiders do live in parts of Indonesia, but they spend their lives in burrows and visitors very rarely meet one. Leave any large hairy spider alone and it will return the favor.

The ones that actually hurt

• Centipedes: Bali's large tropical centipedes, reddish-brown or dark with yellow legs and up to the length of a hand, give the most painful bite you are likely to get here. Expect burning pain and swelling for a few hours to a day. They hide in damp places: bathroom drains, under mats, in shoes and in laundry left on the floor.
• Scorpions: Mostly found in rural areas, under rocks, logs and in cracks. The species in Bali are not regarded as medically dangerous, but a sting is painful.
• Ants: Fire ants and weaver ants (the orange ones that build leaf nests in trees) bite and sting enthusiastically if you stand on a nest or brush a branch. Annoying, rarely more.
• Wasps, hornets and bees: Nests in eaves and garden trees are common. Single stings are painful; multiple stings or any sign of allergy need medical attention.
• Rove beetles: Small orange-and-black beetles attracted to lights. Do not crush one on your skin; their body fluid causes a blistering burn-like rash. Brush or blow it off instead.

First aid for bites and stings

Following standard first-aid guidance such as Australia's Better Health Channel:

• Spider bites: wash with soap and water, apply a cold pack for around 15 minutes and take simple pain relief such as paracetamol. Do not bandage tightly.
• Centipede and scorpion stings: apply a cold pack, rest and take paracetamol. See a doctor if pain worsens or lasts.
• Bee stings: scrape the stinger out sideways with a fingernail or card, then apply cold.
• Rove beetle rash: wash the area gently with soap and water, avoid touching your eyes, and see a pharmacist or doctor if it blisters.

Get medical help urgently for any sign of a severe allergic reaction: swelling of the face or throat, difficulty breathing, dizziness or a widespread rash. Children, older travelers and anyone with allergies should be checked by a doctor after a centipede or scorpion sting. See our emergency information page for numbers and hospitals.

Cockroaches, ants and bed bugs

Cockroaches are part of tropical life, especially in the wet season. They are mostly a hygiene nuisance, not a health emergency. Sugar ants will find a crumb on a kitchen counter within minutes. Bed bugs are not common in good accommodation but can appear anywhere travelers come and go, from budget hostels to smart hotels. Check mattress seams and headboards for small dark spots or tiny reddish-brown bugs when you arrive, keep your suitcase on a rack rather than the bed, and ask to move rooms if you find bites in lines or clusters after a night's sleep.

How to keep a villa bug-free

Open-air living is half the charm of a Bali villa, and it comes with guests. A few habits make a huge difference:

• Close doors and screens at dusk, when insects are drawn to lights. Turn off outdoor lights you do not need.
• Keep food sealed in containers or the fridge, wipe counters at night and take rubbish out daily.
• Shake out shoes, towels and clothes before use, especially anything left on the floor or outside.
• Keep shower drains covered or plugged at night; centipedes come up through them.
• Do not leave wet laundry and bath mats in piles.
• Sleep under a mosquito net in open-sided bungalows; it also keeps out anything that drops from the roof.
• Ask your villa manager about regular pest control, which most well-run villas schedule monthly.
• Love the geckos. The small cicak lizards on your walls eat mosquitoes and moths every night, and the loud tokay gecko is a sign of a healthy garden, not a problem.

Treat Bali's bugs the way locals do: with patience, a broom and a closed door. A little routine keeps the creepy-crawlies outside, where they do their part in keeping the island's gardens and rice fields alive. For other practical health tips, see our guide to Bali belly and our health precautions page.