Sharing my house with wasps

In the South African bush, I've often been forced to share my home with various creatures, but never before with so many wasps. Since we moved from Ndumu GR to Hluhluwe area just over a year ago, I have been surprised by the abundance of the potter wasp Synagris analis. Within a few days of the move, these tiny "drones" did not hesitate to enter and build their nests inside our house. I realised that this was an excellent opportunity to observe them more closely.

Synagris analis  feeding on nectar in my garden.

Synagris analis feeding on nectar in my garden.

Each and every morning, year round, as soon as the doors are opened, they begin the incessant work of collecting mud to start building  or expanding their nests, only stopping late in the afternoon.

The nests have mostly multiple cells. Mud is applied one layer at a time, requiring a tremendous amount of mud-collecting trips. A single egg is oviposited suspending on the inside surface of the cell.

Unlike most eumenines (potter wasps), Synagris analis are progressive provisioning wasps. This means they protect and feed their brood as it develops - other potter wasp species stock all the food their brood need and leave them to develop and grow without parental care.

Once the cell is built and the egg is laid, the Synagris analis sits inside the cell and keeps parasitoids and other predators away, and maintains the nest. After the larva hatches, the mother then constantly provides caterpillars for feeding. Cells are only closed after the larva is ready to pupate and once reaching maturity, it breaks out.
 

A nest with three cells, with one larva under development (top left), one pupating (top right) and a vacant cell by an emerged adult (bottom).

A nest with three cells, with one larva under development (top left), one pupating (top right) and a vacant cell by an emerged adult (bottom).

 Very often, we run into them as they come and go during the day, but they don't seem to be bothered by our presence. The biggest nests are located in our kitchen where I observed some oddities such as two females fighting a territorial battle so seriously that they both ended up on the floor still fighting.

kitchen's nest, with a few vacant cells by emerged adults and a mother guarding her larva (bottom right).

kitchen's nest, with a few vacant cells by emerged adults and a mother guarding her larva (bottom right).

Many different species were also observed using the same nest including another potter wasp Tricarinodynerus guerinii and a solitary bee, with a velvet ant species (Mutillidae) parasitizing some of the brood.

Synagris analis  and solitary bee using the same nest.

Synagris analis and solitary bee using the same nest.

A third cell under construction.

A third cell under construction.

 Currently, a S. analis has started to expand her nest in my bedroom. My husband had a good laugh with this particular individual - when he opened the door to come out of the room, the wasp had been sitting on the floor patiently waiting for the door to be opened so she could continue with her nest building. He said it felt like they exchanged a moment as she then calmly flew up and past him and straight to the nest in an adjoining room.

Synagris analis  inspecting her nest in our bedroom. 

Synagris analis inspecting her nest in our bedroom. 

 

Unfortunately, every now and then I find a few S. analis struggling or already dead, either lost in the maze of a human structure (the newbies) or with their usual doorways and windows closed due to winter weather. Flying costs energy ("time is honey!") and if one is trapped in the house for too long, death is certain. I have managed to save many by feeding them molasses. It is incredible to see how fast these animals can recover.
 

They have quickly become part of our daily life and watching them go about their business brings a huge amount of joy. Despite our close proximity and regularly bumping into each other, no one in the house has ever been stung by one of these beautiful animals and they are clean, peaceful and industrious - the perfect roommate!