Working in an entomology department, insect death is all around me. It's one of the unfortunate parts of the job, that I've always had mixed feelings about.
But there are some really good reasons why sometimes we have to kill bees to save bees.
If we want to identify wild bees to species, you have to be able to look at it under a microscope, and compare it to reference specimens. Unlike birds and other animals, it is impossible to identify the wide diversity of bees “on the wing,” which means being able to identify a species just by looking at it in the field. And not all bees are created equal - we have specialists and generalists, social and solitary bees. Knowing which bees we have in a community is a vital part of identifying the functional role of bees in the ecosystem.
Furthermore, bee identification errors are incredibly common, and can lead to misrepresentation of a species’ current status. This can be a big problem when we are trying to evaluate a species of concern - an invasive species suspected of increasing in abundance, or a rare species suspected of significant population decline. Because bees can be so hard to correctly identify, we often have to send bees we catch in the field to expert taxonomists. Unfortunately, mailing live bees is not yet possible, and would come with a whole deluge of issues in terms of exotic species transport.
Also, species names can change. As we continue to study the evolution of bees and bee taxonomy, we better understand the relationships between species (largely thanks to awesome new molecular techniques). So while we may have called a group of similar looking bees the same species 30 years ago, we may figure out that it’s actually better classified as two separate species. Being able to go back and identify where naming errors occurred in the past allows us to accurately track changes in diversity and abundance over time.
Finally, we all hope that our collections are just a drop in the bucket. That collecting bees from a site will not change the overall bee community. Bees are small and pervasive. It would be quite a feat to collect enough of them to make a difference. However, if this underlying assumption ever proves to be false, we will have to come up with alternatives to killing. And, should that day come, I look forward to recommendations for alternative methods.
So, I don’t have to like killing bees. I am, after all, dedicating my life to conserving them. But it is, at least for now, a necessary evil.
And some pictures of very alive bees to make us all (mostly me) feel better :) -