The Complete Guide to Wasp Prevention, Treatment and Control in Singapore

Wasps, a group of flying insects in the order of Hymenoptera, are often confused with bees because of their similar shape. Both can build nests in trees, attics, balconies and at the corner of ceilings.

Wasps and hornets are from the same family, Vespidae. They are beneficial insects and play essential roles in the ecosystem. They help in pollination and prey on insect pests. Without wasps, we would be dealing with more insects, pests and spiders. Nevertheless, the presence of wasps may cause stress and disturbance to humans because of their painful and dangerous stings.

Table Of Contents

• • Types of Wasps in Singapore
  • Life Cycle and Biology
  • Hazards of Wasps
  • Secondary effects from wasp stings
  • Signs of a Wasp Infestation
  • Tips to Prevent and Get Rid of Wasps
  • DIY Methods to Get Rid of Wasps

Wasps can be distinguished between social wasps and solitary wasps. Social wasps share one nest, while solitary wasps nest alone. Hornets, yellow jackets, and paper wasps are examples of social wasps. On the other hand, thread-waisted wasps and mud daubers are characterized as solitary wasps.

Social wasps:

Paper wasps 

Paper wasps are said to be the most common type of wasp in Singapore. Paper wasps have reddish-brown to black colour bodies with yellow rings around their abdomen. They are also called “umbrella wasps” because their nests resemble an upside-down umbrella supported by a single stalk.

Yellowjackets 

Yellowjackets look quite similar to paper wasps. However, paper wasps have long and slender legs. The most common yellowjackets have bright yellow bodies with black lines, spots and triangles on their abdomen. Their body size is around 0.9 to 1.5cm. 

Unlike paper wasps, yellowjackets use wood fibre to construct their nests. Yellowjackets may build nests in wall voids and attics, but they rarely cause structural damage to premises. Besides, they also build nests below the ground (not active rodent burrows), hollow logs, timbers or trees.

Hornets 

People most often refer to yellowjackets as hornets. However, some hornets are much larger (can be up to 5cm) than yellowjackets. They can construct round or pear-shaped paper nests up to 90cm long. An entrance hole is always situated near the bottom of the nest. Hornet nests are most often built above ground, in high trees. However, they may attach their nests to the eaves of the buildings.

Solitary wasps:

Mud daubers 

Mud daubers have longer and slender waists compared to most of the other wasps. Their body sizes range from 2 to 2.5cm. Nests of mud daubers are much smaller. They build mud tubes under buildings, roofs or attics.

Thread-waisted wasps 

Thread-waisted wasps have incredibly narrow waists with a red or orange band between the waist and the abdomen. They also have long and skinny legs. The body size can be longer than 2.5cm, bigger than mud daubers. Thread-waisted wasps are ground nesters. They construct nests and seal them temporarily just before going out and searching for food.

A wasp nest is generally started from a solitary queen/female wasp. She will first build a small nest and raise the first generation on her own.

Social wasps 

Social wasps have a caste system in their societies. One caste can have one or several queens. The workers are sterile females. A few drones (males) can also be found.

A mature paper wasp nest rarely has more than 200 cells and the nest usually contains 20-30 adults. Most social wasps have annual nests (survive a year). Social wasp workers typically have a lifespan of 12 to 22 days, while the queen usually can live up to a year.

Solitary wasps 

Solitary wasps are also predators. Adult wasps feed on nectar and prey on insects or spiders to feed their young, just like social wasps. Different species of solitary wasps attack different types of insects. They sting, paralyze, drag or pick prey back to their nest. The larvae of the solitary wasp will then feed on the immobilized prey for their development and growth.

The ability of wasps to sting is the primary reason that people are worried. Wasps sting and inject venom from the rear part of their abdomen. Social wasps will vigorously attack humans when their nest is disturbed.

Nonetheless, they rarely sting away from their nest unless they are trapped or pressed against human skin. On the other hand, solitary wasps rarely sting unless threatened. The sting from solitary wasps usually causes a less severe reaction to humans than social wasps.

Wasp stings result in pain. Often, wasp stings are more painful than the sting of bees. The stings from wasps are usually not life-threatening but can last for a longer period. Allergic reactions may occur in some people. In severe cases, they may suffer an anaphylactic (hypersensitive) reaction if they are stung by the wasps. However, most deaths from wasp stings are because by allergic reactions to venom protein and enzymes from the wasps.

After being stung by a wasp, most people will only experience minor pain and swelling on the skin, while there are still many other symptoms that can be resulted from the sting of a wasp: 

• Pain 
• Redness
• Swelling
• Itching
• Flushing

Victims should seek medical care immediately if severe allergic reactions start to develop. Symptoms in more severe cases can be: 

• Widespread rash 
• Anaphylaxis  
• Difficulty breathing 
• Rapid pulse 
• Low blood pressure
• Shock/respiratory distress

The best thing to do is to run to a protected area to prevent social wasps from stinging continuously and avoid danger.

There is another problem resulting from getting stung by a wasp. Many people panic if there is a wasp around. Secondary hazards can occur if a person sees a wasp and suddenly starts running without noticing their surroundings. For example, this may happen while crossing a road.

1. Sighting of wasps 

This is quite an obvious sign that can tell you if a wasp nest is somewhere near you. You might need to follow and trace wasp nests if you wasps flying around your premises. What you can do is follow their flight path and check for the nest location.

2. Buzzing wasps 

Buzzing happens especially when social wasps are around. This is because of their large number. The buzzing sound may give you a cue to locate their nest. 

 3. Sighting of wasp nests 

You may do a thorough check around your house after noticing the first and second signs. Wasp nests can be found in trees, inside lofts, edges of roofs, in the corner of a quiet room, or even inside a wardrobe.

How to prevent wasps? It is almost impossible to eliminate wasps from us entirely as they are part of our ecosystem. Nonetheless, we can try to reduce their access to our living environment and make it less suitable for them to breed.

1. Eliminate new nests before they become a threat

It is usually safe to destroy a wasp nest when it is still in the earliest stage of development. However, if you are worried about the possible hazards, you may call a pest management professional to handle them.

2. Seal any openings that can be potential entry points for wasps 

You can inspect and check around your house’s exterior. Use durable materials like caulk-based silicone, metal screen or similar sealant to repair or seal any openings, cracks or gaps that might harbour a wasp colony. 

3. Reduce clutter 

It is essential to reduce clutter in and outside of the house. Unused items such as lawn equipment, appliances or unwanted receptacles can attract and provide shelter for wasps to build their nest, especially when food and flowers are around.

4. Do not leave any food outside 

After enjoying your dinner or barbecue in the backyard, always make sure to clean up immediately.

5. Make sure garbage bins are covered completely

Garbage bins can be one of the popular nesting sites for wasps because of the moisture and food. Make sure the bin lids are clamped down securely and inspect for any crack or hole on the surface of the bins.

6. Avoid overripe fruit in your garden area 

If you are planting fruit trees in your garden, make sure to check to avoid overripe fruit frequently, as these attract wasps. You may also seal the fruit in a plastic bag or container to not attract wasps to come over.

There are a few DIY methods that might help to deter wasps from nesting around your house. These methods make use of the smell released from natural oil blends or plants.

1. Use of essential oils 

Research has found that a combination of lemongrass, clove and geranium essential oils can successfully repel wasps. Mix several drops and apply the oils on potential nesting sites such as edges, roofs, cracks, and crevices. Furthermore, you may also target those areas that were previously occupied by a wasp nest.

2. Place/plant wasp-repelling plants around your house 

You may plant some wasp-repelling plants around your house instead of those flowering plants that may attract wasps from coming in. Mint, eucalyptus, citronella, marigold, basil and geranium are some examples of plants that wasps find distasteful. You may also cultivate those plants indoors if you spotted wasps in the area before.

Wasp management is best left for professionals because of its hazards and challenges in applying chemicals to the wasp nest. Pest management professionals are always equipped with the proper PPE (personal protective equipment) when dealing with bee or wasp nests. The PPE prevents them from getting stung.

Our trained pest management professionals use an effective chemical delivery system to reach wasp nests with an aerosol generator. The chemical or insecticide acts on the entire wasp colony and the nest is then removed from the infested area. 

If you have wasp issues in your house or premises, please do not hesitate to contact Killem’s team. Our trained pest management professionals can help you get rid of your worries and make you feel safe again.