Can Bees Sting Other Bees?

Question
I was wondering, can bees sting other bees, especially bumble bees?  Also, if they do, will a bee die if it stings another bee?
- Katja, USA

The short answer is:
Yes, if equipped with a stinger, bees can sting other bees.  Such events can happen among bumble bees when conflict arises, either within colonies, between colonies of the same species, or among different bee species. 

The individual that will die as a result of a stinging incident between bees, is the bee that is stung rather than the bee delivering the sting.

To an extent, I have largely covered this question on my page do bees fight each other.  However, it’s perhaps worth expanding on this question further.

When and Why Bumble Bees Sting Other Bees

It sometimes comes as a surprise to people when they learn that bees can and do sting each other to death.

It is perhaps especially strange to think of the cuddly-looking bumble bees using a deadly sting on another bee, but it has to be remembered that one of the purposes of having a stinger, is for self-defense, which in turn is about survival.

Thus, in any scenario in which bees are threatened in their bid to survive and thrive, they will use their stingers (if they have a stinger - not all bees do), including against each other, or against bees of other species if necessary.

Competition for nest sites

Bumble bees may use their stings against each other especially when there is competition for nest sites. 

Good nest sites are not always easy to find for the new queens.  For this reason, once a nest site has been discovered by more than one queens, conflict can occur with one queen stinging the other to death. 

The competition for a nest site, is in a sense, a very real fight to survive and to thrive, with both queens having a strong instinct to rear young and ensure the survival of their own species, and their own genes.

As an aside, humans can perhaps help bees out in this respect by ensuring their garden is as bee-friendly as possible.

Hedgerows, wild scrubland and meadow, outer verges around woodlands, all tend to offer the best kinds of sites, and so suitable nest sites are probably even harder for bumble bees to find these days due to modern farming, land management and possibly even gardening practices. 

Conflict with cuckoos

The arrival of a cuckoo bumble bee in the nest of a foundress queen, could at some point, also provoke a fight and sometimes a stinging incident, in which:

• a cuckoo is killed by bumble bee workers and / or the queen (though perhaps not immediately) and / or 
• the host queen and some of the workers are also killed. 

There may be different scenarios depending on cuckoo species and host in which cuckoo and host queen cohabit in the nest together..

Will a bee die if it stings another bee?

This question may arise because of a misconception about bees and stings: i.e. that all bees die if they sting humans. 

This is actually not the case (it typically applies to honey bees stinging humans (or animals and birds), and the lodging of the barbed stinger in the skin).

Whatever the species, if a bee stings another bee, then one of those bees will die, and it’s the one on the receiving end of the sting.