Black Widow Spiders Eat Their Mate – True or False?

black widow spiders

A black widow spider.

We have all heard the horrific story about how female black widow spiders will eat the male after they mate.  But, do you know if that is actually true?

For all animals mating and reproduction play an important role in our lives.  As a male and father I am aghast when I think of being eaten by my mate after mating.  I just can’t imagine that happening.   Sadly though, it does in fact happen to some black widow spider males.

What Is The Black Widow Spiders Myth?

The myth states that the female will eat the male after they mate.

black widow spiders

The red hour glass of the black widow is a sure sign of this deadly spider. Photo via Flickr.

Is It True That Female Black Widow Spiders Eat The Male?

The answer to this, similar to the answer to many myths, is yes and no.

It is true that the female will sometimes eat the male after mating, but that does not always happen. It depends on the species of Black Widow.

There are many different species of Black Widows in the world.  The only known species whose female always eats the male after mating lives in the Southern Hemisphere.

In the United States there are three species of black widow spiders.  The only species in the Rocky Mountains and west of Kansas, the Western Black Widow, has never been observed eating the male in the wild.  Of the three species, the only one that sometimes will eat the male is the Eastern Black Widow.

black widow spiders

The male western black widow spider is smaller than the female and a different color. Photo via Flickr.

Why Do Female Black Widow Spiders Eat Males?

This is a question that scientists have wondered about and researched for a long time.  The latest findings indicate that the females do this simply because they are much bigger than the male and they are hungry.  Research shows that if the male is much smaller than her, the female will eat him.  But, the female will not eat him if he is a larger male.