Wasp Nests – To Remove or Not to Remove?

When I became a beekeeper, little did I know that so much of my time would be taken up by insects that are NOT honeybees. Like bumblebees, solitary bees, varroa mites, woodlice and wasps. I even encountered a very rare Death’s Head Hawk Moth at one stage! As beekeeper, I am often asked to remove or rehome all kinds on critters. Mostly swarms of honeybees or honeybee colonies, bumblebee nests and wasp nests. But do wasp nests always have to be removed? In what situations can they be left alone, and how should you go about removing a wasp nest safely? Read on for all you need to know about wasps, how they live, how to determine if a nest should be removed or not, and how best to do it.

When I get called out to remove a nest, many times the homeowners do not know exactly what type of insect it is. So, unless I get a picture of the nest or insect, I don’t know either until I get there. The owner of the home where this wasp-nest was removed from thought that they had a colony of honeybees in the attic, but it turned out to be a gigantic wasp nest! I just had to strap it onto the child seat on my bike and bring it home to show my little boy!

Are wasps good or bad?

Because wasps fly and forage at low temperatures, they are hugely beneficial for pollinating crops that flower early in the year, or in years with poor weather conditions. They also prey on garden pests such as aphids, which can make them a welcome addition to a garden. However, they do sting. Unlike honeybees whose sting detaches from the bee after stinging, resulting in the death of the bee itself, wasps have a retractable sting. It can be likened to the claws of a cat. Because of the sting, and perhaps also their ability to use it as often as they feel the need for, many of us do not want wasps or wasp nests in the vicinity of where we live. They can also be a nuisance in the summer, when they look for food. Spoiling many picnics, barbeques and al-fresco lunches with their persistent presence.

Because of our fear of wasps, our first instinct is often to kill any wasps or wasp nests that we come across. But, considering how beneficial they are for the eco system, perhaps we should be a bit more lenient. Especially with wasps that have chosen a nest site that do not interfere with our daily lives.  

What do wasps eat?

Because wasp colonies don’t live during winter, they do not make and store honey like honeybees do. Like bumble bees, they live more day-to-day. Which is probably why they have evolved to fly and forage in colder, wetter and harsher conditions than honeybees. Wasps eat different things depending on how old it is.

Sugary foods

Adult wasps eat mainly sugary foods. Such as honey, sugary human food, nectar, fresh fruit and fruit that have started fermenting (they sometimes get a little drunk from this!). They also eat the sugary excretions from larvae, aphids and other sap sucking insects (honeydew). Wasps are attracted to honey and honeybee colonies. They can easily wipe out a small, weak or badly protected honeybee colony as they raid it for food. Because of this, many beekeepers put up wasp traps and reduce the entrances to their honeybee colonies in late summer in an attempt to stave off robbing from wasps.

Meat and insects

Adult wasps are also often seen collecting meat from roadkill, barbecues, insects etc. However, they do not eat this themselves. The meat is brought back to the wasp nest. There it is used to feed the larvae this highly nutritious food before they pupate and then emerge as adult wasps. Wasps collect meat as long as there are larvae in the nest. Towards the end of summer, they will stop collecting meat as there are no larvae left to feed. This is where we often experience masses of wasps feasting of anything sweet and they become a real nuisance as we try to enjoy the last of the season’s outdoor dining.

One thing that we can do to deter wasps from coming into our homes and outdoor dining areas in search for food, is to simply make sure not to have those kinds of foods lying around. Cover meat, jams, honey and sweet drinks accept for when using. Properly discard old food. Also make sure that bins and compost bins are well sealed. Wasps foraging on the plants in your garden should be welcomed. They are unlikely to cause any trouble to you.

Lifecycle of wasps

The lifecycle of a wasp is very similar to the lifecycle of a bumble bee. In short, the only wasp that lives over winter is a queen wasp. Queen wasps are ‘born’ late in the summer. The virgin queens then go off to mate with wasp drones before the onset of winter. She then eats herself fat and finds a good spot to hibernate for the winter. Inside her she carries eggs, and stored sperm from when she mated in the autumn. She has all that is needed to start a new colony. Any queen that survives the winter will build a nest of her own and start a new colony in spring. These queens are the only wasps that survive from the previous season. All the rest of the wasps, (the old queen, female workers, and drones) die in the autumn.

In the summer, a wasp nest can be home to several thousand wasps. In the autumn, depending on the size of the nest, hundreds of virgin queens are produced. These queens can go on to mate and build new nests the following year.

Queen wasps hibernate in winter

Wasp queens hibernate in the winter, but not inside a wasp nest. You will often find hibernating queen wasps attached to logs in a wood pile, folded up garden umbrellas, or other dry, sheltered areas. As a beekeeper I often find hibernating wasp queens under beehive roofs or on old equipment. If you happen to find a wasp inside the house in the winter, it is likely she came inside on a log or similar that you brought in for the fire. Because of the change in temperature, the queens wake from hibernation once they come inside. They can fly around, but usually they are quite lethargic and walk around mostly. Although they can sting, they would not be likely to do so, and the best thing to do is just to capture her and leave her outside to give her a chance to re-enter hibernation.

This Queen wasp came inside in January with a load of logs for the fire. She was dazed and as you can see had absolutely no interest in stinging me…

Wasps build new nests every year

Because of the lifecycle of wasps, each nest is built from scratch in the spring. Queen wasps that have hibernated over winter wake from their hibernation and start building her nest. This means that any wasp nests can be safely removed in the winter as there are no wasps in them. Unlike honeybees, wasps do not nest in the same nest consecutive years.

Wasp nests can range in size quite a lot, from the size of a golf ball to much, much larger. They are built from wood which wasps collect and chew to make pliable. They are papery in texture and quite brittle. Within this beautiful exterior, lies the nest itself, with cells where the queen lays eggs and the young wasps are raised. There are also wasps that build nests in the ground. Sometimes you will find small, abandoned wasp nests early in the season, about the size of a golf ball. These nests have been started by a queen and then for some reason abandoned, either something happened to the queen, she could have been disturbed or she found another, better, site to build her nest.

Where do wasps build their nests?

Because the nest is built from pulp, is papery and brittle, it needs to be protected from the elements. Wind and rain can damage the nest. Wasps will often build nests in attics, roofs, outbuildings, trees etc. The Queen will start the nest herself, and when the first batch of female worker wasps have emerged, they will take over the building of the nest. As the colony grows, the size of the nest increases, and in the ‘right’ conditions wasp nests can get very large.

Wasps are not always very considerate of their human neighbours, and because our houses have perfect sheltered areas, they often decide to build their nests inside ours.

Should you remove a wasp nest?

The question of whether or not to remove a wasp nest is a very personal one. You have to take a lot of things into consideration and make the right decision for you and those around you.

1. Timing. What time of the year is it? In spring, nests are often very small and can easily be removed if they are located in an unsafe or unsuitable place. If it is late summer or autumn, there may be little point in going through the expense and trouble of removing a nest unless it is a nuisance, as the colony will die off in a matter of weeks anyway.
2. Position or location of nest. Is it causing a nuisance or danger, or is it likely to?
3. Are there people with allergies, children or pets nearby who could be affected?
4. Is the nest active or is it empty?
5. If you are removing it, who will do it?

Removing a wasp nest in the summer

If a wasp nest has to be removed in the active season, when there are wasps in the nest, the nest is usually destroyed. Before attempting to destroy a wasp nest, make sure that the insects are indeed wasps and not bumblebees or honeybees. Bumblebee nests are best left in situ or relocated if it is absolutely necessary to move them. Relocated bumblebee nests unfortunately often do not survive. Honeybee colonies or swarms should be removed by a beekeeper and absolutely not destroyed. Please contact your local beekeeper’s association for more information or go to www.swarms.ie

Wait until evening, night or early morning to make sure all wasps are in the nest. If you attempt to destroy a nest during the day when many of the wasps are out foraging, they will return to the nest site. And you will have a lot of wasps hanging around for at least a few days. They might even start a new nest nearby.

Make sure to wear protective clothing. Wasp stings can be very, very painful. And if you get one, you are more than likely to get several. Even if you are not allergic to wasp stings, you can have a bad reaction. The swelling and soreness resulting from even a single sting is not that pleasant either.

Also make sure that any bystanders wear protective clothing and are aware of what you intend to do. Ensure children and pets are nowhere near the nest.

A beekeeping suit or similar is good to wear if removing a live nest of wasps. Be sure to wear thick gloves as well though…

Use water

If the nest is very small and you do not want to kill the wasps but to get them to relocate, you could wet the nest a few times. This should be enough to make the wasps realise that it is not a good nesting site. They should then relocate to another spot. Hopefully more suitable for both them and you. Water should never be used on a large nest. This is because you will have a lot of irate and displaced wasps flying around causing nuisance. The only exception is ground nesting wasps, which can easily and successfully be removed with water, preferably boiling water.

Use fly spray

One of the easiest ways to destroy an active wasp nest is to use fly spray, widely available in many stores. The nozzle should be either pointing at or inserted into the main entrance to the nest. You can then spray the nest. When you do this, there will be a lot of activity in and around the nest as some wasps will fly out and try to attack. If it is possible, to prevent this, you could first place a large plastic bag or bin liner over the nest and secure the openings. Then make a hole large enough for the spray bottle. If you do this, any wasps flying out of the nest will be trapped inside the bag and will eventually die also.

Removing hard to get to nests

Nests that are hard to get access to but that still need to be removed should be dealt with by a professional with the right gear. Advice will often state that you should try to block up all the entrances to the nest. You could do that, but chances are that the wasps will find or make a nest entrance/exit and you have to start from scratch again.   

Should you remove an old wasp nest?

As already discussed, all wasp nests are empty in the winter. Except of course if another insect or animal has taken up residence there. Wasps do not reuse a nest. Therefore, there is no fear that an old nest will attract wasps the following season. Despite this, many people are eager to remove old wasp nests. However, it might surprise you that there can in fact be very good reasons for leaving the old nest in situ.

Old nests can deter new nests

It is thought that old wasp nests can in fact deter wasps from building a new nest in that area. This is because a queen might be unlikely to build her home in an area that is already taken. There may be some truth in this, and some people even go as far as placing wasp nest decoys on their properties to deter queens from starting nests in the vicinity. What speaks against this though, is that it is not at all unusual to find several wasp nests close together. However, it is possible that a large wasp nest can deter smaller nests being started in an area. And at the same time that queens who start their nests at around the same time do not feel threatened by the presence of other, similar sized, nests in close proximity to her nest. So both scenarios may be true.  

If the old wasp nest has remnants of insecticides, it does serve as a deterrent for other wasps. Hence, there is very good reason for leaving such a nest in place.

Reasons for removing old wasp nests

On the other hand, there can also be some very good reasons to remove old wasp nests.

Contractors may not want to carry out work in an area which has a wasp nest. That has been true for me on several occasions, where I get a call to remove an old wasp nest that was revealed during building work or renovations. In these cases, it is often easier just to remove the nest than spend valuable time trying to convince people that the nest is empty and is not potentially harmful.  

Old nests can become home to other unwanted insects or animals.

Being made from paper, wasp nests are dry and can easily become a fire hazard.

How to remove an old wasp nest

If you choose to remove a wasp nest in winter, or the inactive season, this can be done so that the nest remains intact and can be studied. Believe me, it really is a thing of beauty when you get up close and personal! Always check first to make sure that the nest is in fact empty. Old nests can be very brittle and break up easily when handled. It is a good idea to use a facemask. Then you do not accidentally breathe in the dust and debris (could contain insecticides as well) from the nest. Place a bag or bin liner around the nest and gently remove it. Bring it outside and lay it on the ground. You can then unfold the bag and take a closer look. The contents can be composted or simply placed in the garden to be broken up by the elements.

Caution

Always wear PPE when handling active wasp nests

Always make sure to positively identify the insect so that you do not accidentally kill or damage honeybee colonies or bumblebee nests.

If you are removing a nest and it goes wrong, you get lots of stings or the wasps are very aggressive, then abort mission. Either call in the professionals or come back another day better equipped.

I hope you enjoyed reading this blog. If you have any questions or comments, please use the comment section below. Also check out my other blogs about all things honeybee over in the blog section /Hanna

Hanna Bäckmo

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