Composting Worms Stuck Together

Have you been looking through your worm bin and found composting worms stuck together? Did you wonder what was going on?  This is how red wiggler worms mate.  Now that your curiosity is satisfied about this strange phenomenon you’ll want to understand more about what is going on.

Composting Worms Stuck Together and the Clitellum

The clitellum is the enlarged band around the worm’s body that is close to the head of the worm; maybe 1/3 to 1/4 of the way back from the head.  Sexually immature worms do not have clitellum.  This is they way to tell if a worm is ready to mate.  Composting worms are hermaphrodites.  This means that each worm has male and female parts.  But they cannot mate with only themselves.  They need another worm to line up with, in order to exchange sperm.   Worms attach to each other first with their setae which are defined as:

Each segment or section of the worm has muscles and bristles called setae. The bristles or setae help anchor and control the worm when moving through soil. This information came from the website of the University of Pennsylvania which has lots of good explanatory pictures.

The worms align themselves in opposite directions.  A good drawing and explanation can be seen at this composting website.  After attaching and holding onto each other with their setae (bristles) they create a slime tube which enables the transfer of sperm from worm to worm. The slime tube also becomes the cocoon.  Please check out these links because pictures are worth thousands of words!  Below you will see a YouTube movie that I put together which also demonstrates what happens when worms mate.

Mating Process Can Take Up to 3 Hours

Even though each worm has male and female parts, the seminal fluid must be exchanged between worms for fertilization to take place.  There are grooves on the underside of the worm that enable the exchange of sperm.  The exchange of sperm doesn’t necessarily happen at the same time.   The process can take place for up to 3 hours.  This is a very good website to explain this process: the city of Euless, Texas.  Charles Darwin has some things to say about worms at this link, an excerpt from a book called The Earth Moved.  Read pages 69 and 70.  He is talking about nightcrawlers so it is not clear to me if this applies to red wigglers. It is very interesting anyway.

Composting Worms Mating Video

I found some composting worms stuck together in one of my worm bins, so I decided to take a video of them. I don’t know if they are still mating in the video or if they are trying to separate.  They want to escape from the light.  As they are trying to separate or mate, whatever they are up to, the worm at the back seems to have its head in the slime tube.  The video gives an excellent view of 2 composting worms mating.