Wasps!

[Gengh]

This is Vespa tropica, the greater banded hornet, one of the biggest and more common hornets in Singapore. This species is a predator on nests of other social wasps and bees. In fact, I believe that if you leave that nest alone, it is only a matter of time before these hornets attack and wipe the colony out, driving the adults away and capturing all larvae and pupae to feed their own offspring. A colony of these hornets in tropical areas like Singapore may well have to attack 500 or more colonies of paper wasps or honeybees throughout its lifespan!

These nests don't grow so fast, so a week isn't enough to see a difference in size. But they are often building on extremely thin plant stems so it doesn't seem that the branch is too thin to support them.

Thanks again vespa for the interesting and useful facts. So how would I know if the paper wasps are still there? What is the best time of the day to observe their activity? I would like to, as wxwayne said, live and let live, but letting the nest grow is probably not an option. Maybe if hornets have already gotten to them, I wouldn't have to do the dirty work then.

 

[vespa_bicolor]

Hi vespa_bicolor,
Thank you for the detailed explanation and clarification and the valuable photos.
It's indeed a good lesson for me, clear up some of my misconceptions.

Hi Gengh,
Forget to mention that you have some nice photos there.

No problem! Always glad to share what I've learned through the years about these fascinating and often misunderstood insects.

Talking about mud dauber, would you mind to help me ID these hives on the wall outside my room?

Apparently they really like the location despite repeat removal by the cleaners.

Thanks!

Those would likely be mud-dauber wasp (species of either Chalybion or Sceliphron) nests. It sometimes happens that a particular location is particularly attractive to them, and repeated cleaning fails to deter them. If that happens, spraying of insecticide on the location after destroying the nest will work. However, since solitary wasps will never actually attack, it is best to leave the nests alone.

Wow, you brought a full strobist setup out for a nest! :bigeyes: Impressed at your professionalism.

:bsmilie: Agree!

 

[vespa_bicolor]

Thanks again vespa for the interesting and useful facts. So how would I know if the paper wasps are still there? What is the best time of the day to observe their activity? I would like to, as wxwayne said, live and let live, but letting the nest grow is probably not an option. Maybe if hornets have already gotten to them, I wouldn't have to do the dirty work then.

They are active throughout the day in Singapore, from about 6 or 7 a.m. to 7p.m. The nest of most paper wasps is open, with the cells clearly visible and not hidden under a protective shell, so if there are wasps on the nest you will definitely see them. It sometimes does happen that due to unknown factors (environmental disturbance, chemicals being used in the vicinity) they may abandon the nest. If you see the nest totally empty without any wasps, it will have been abandoned and they won't come back. If in addition to the absence of any wasps, the nest looks tattered and torn, the cells look like they've been partly ripped up and the larvae are all gone, the nest would certainly have been a victim of hornet attack.

 

[maddyks]

Woah that's a amazing amount of information you have there man. And mainly, thanks a lot for sharing and in such a nice way.

 

[Gengh]

They are active throughout the day in Singapore, from about 6 or 7 a.m. to 7p.m. The nest of most paper wasps is open, with the cells clearly visible and not hidden under a protective shell, so if there are wasps on the nest you will definitely see them. It sometimes does happen that due to unknown factors (environmental disturbance, chemicals being used in the vicinity) they may abandon the nest. If you see the nest totally empty without any wasps, it will have been abandoned and they won't come back. If in addition to the absence of any wasps, the nest looks tattered and torn, the cells look like they've been partly ripped up and the larvae are all gone, the nest would certainly have been a victim of hornet attack.

The aftermath of a hornet attack sounds scary... :sweat:

I'll check it in the day this weekend, see if I can spot them at the nest.

 

[pwrpufguy]

welcome to national geographic chl, great info u've got there Vespa, ive learnt alot abt them

nice pics Gengh!

 

[Gengh]

welcome to national geographic chl, great info u've got there Vespa, ive learnt alot abt them

nice pics Gengh!

Thanks!

 

[Darcy.Zhou]

Actually, do not under-estimate the danger of wasp.

Note :
I'm not trying to talk shop here. I was attacked by hundreds of bees (thanks god, not wasp !) when I was a child when my stupid neighbour thrown a stone at a huge bee hive.
If it was a wasp hive, I won't be here to type these words.

 

[Gengh]

Just an update on the wasps, I've checked the nest several times these past 2 days, and I've not noticed any activities. It doesn't look all torn up either. So I guess they must have left on their own accord for some reason

 

[vespa_bicolor]

Yes, could be. It's a bit early in the colony cycle for them to abandon the nest, but actually the biology of wasps in tropical regions is still poorly studied, and they do things that surprise us all the time. Alternately, if the larvae and pupae are absent from the nest, but the cells don't look torn-up, they could have fallen victim to ants. Ants and big hornets are the main enemies of small social wasps in the tropics.