Montana Public Radio

Bug Bytes: Burying Beetles And Mites

Jun 16, 2020

Burying beetles are often called sexton beetles since they perform duties similar to a sexton or gravedigger.

These beetles have an amazing ability to locate fresh carrion from long distances, allowing them to find this valuable food source before competing scavengers do. But rather than consume the departed mouse, vole, shrew or other small vertebrate for themselves, they have other plans.

Credit Photo courtesy of Kyle Hartse

Working together, a beetle pair will move the carrion into an underground burrow. The female will then lay her eggs near the soon to be decomposing carcass. When the eggs hatch, the adult beetles display a level of parental care rarely seen in the insect world – they stay around to feed their developing beetle larvae regurgitated carrion.

Yum. Thanks, Mom.

But as you might guess, there are other things that like to make meals of recently deceased meat sources…in particular, flies and their maggot offspring.

To help ensure the burying beetle’s hard earned protein source is left for their own young to eat, they enlist help from a seemingly unlikely source…mites.

It turns out the mites like to feed on fly eggs. But if you’re a tiny little mite, finding reliable sources of fly eggs for a meal can be highly unpredictable at best.

To significantly increase the odds, the mites live on burying beetles, using them as a form of carcass-to-carcass transportation to find fly eggs.

In return, the mites eat the fly eggs on and around the burying beetle’s carrion stash, preventing maggots from hatching that would otherwise compete for the beetle’s prize.

Just another example of an amazing symbiotic relationship in the insect world.