others beasties in paradise city ...
Scorpions can be found at ground level all over Thailand and Hua Hin is no exception. They can be either grey, brown or black and are poisonous, although the venom is not strong.
A sting will result in extreme pain and some people can be allergic to it. Careful cleaning and disinfection are necessary to prevent infection.
Centipedes are also common in Hua Hin, again mainly at ground level although they can climb as well. Their poison is mild, but a bite will result in swelling and extreme pain. There is a very real possibility of serious infections afterwards, so a visit to a hospital is recommended.
You may come across bird spiders in Hua Hin and although their bite is poisonous, it is no more dangerous than a bee or wasp sting. Some people may be allergic and so the victim should be carefully watched and the affected area well cleaned and disinfected.
Most of the remaining insect and animal life around Hua Hin can be viewed either as an annoyance, or vary rarely seen. Into this category should be mentioned ants. The ones that you're likely to come across in your home are only looking for food and not aggressive. However hard you try to get rid of them, they'll always come back for more. Unless you manage to destroy the nest and the queen with it, the colony will always be around.
However, outside in your garden or in the countryside you may come across more aggressive and painful species. Red ants, as almost everywhere in the world, will bite but it's more an irritation than anything else. The small black ants are worse and a bite can itch for days. Additionally, there are fire ants and soldier ants. A bite or sting from these (and they can deliver both) will be painful, similar to a bee sting. They are fiercely territorial and will attack if you come too close to their nest. 20-30+ of these crawling over you at the same time is no joke.
As with any sub-tropical destination, you'll encounter your fair share of lizards here. House lizards are common and a blessing in disguise as they'll eat mosquitoes. "Tookays", so called because of the distinctive call they make, are larger, mainly seen outdoors and of no danger. However, you should be careful of monitor lizards. You're hardly going to meet one in central Hua Hin, but you might in the countryside or on a national park. They can be extremely hostile and are always likely to thrash out with their tail if disturbed. This can be a very painful experience. In addition, they have large claws and big teeth. This reptile is a relative of the infamous Komodo Dragon that's found only in Indonesia, and as such should be given a wide berth and not provoked.
Not all of the coastline around Hua Hin is sandy. If you are close to rocky areas or any coral, be careful of dragonfish and rockfish. Both live in rocky habitats and can be difficult to spot. The former is very aggressive and a sting will produce immediate pain and swelling. Do not try to administer first aid. Get medical attention as soon as possible.
Rockfish are notoriously difficult to see as they blend in so well with their surroundings. They are extremely poisonous and are one of the most dangerous marine creatures. A sting will result in extreme pain and swelling straightaway and can be fatal. Again, seek medical attention immediately.
At certain times of year, especially in the rainy season and when sea conditions are rough, jellyfish can be washed in close to shore all around Hua Hin's beaches. Many are completely harmless, but others come with an extremely painful sting. If you are unlucky enough to came into contact with one of these, most beach bars and restaurants will have an antidote to apply immediately and this will reduce the pain and take care of any stingers that have not yet burst. You should visit a hospital as soon as possible thereafter for proper first aid. This will lessen the chances of infections developing and can help with possible scarring.
Finally, it is possible to come across sea snails that are washed up on the beach. They live in conical shells in deep water, so you're not going to come across them whist swimming. However, if you find one on the beach, don't touch it. If the snail is still alive, it will inject a highly toxic poison that will produce extreme pain and even death. There is currently no known cure and medical attention is vital immediately.