Love Life of a Mantis

Siren Song of the Mantis Temptress

For those of you who have been diving in Lembeh Strait, maybe you already know how crazy-powerful and violent mantis shrimps are, either spearing or smashing prey and pretty much anything else that gets in their way. Maybe you have already heard how advanced their eyes are, that they are able to see ultraviolet light, infrared light, Elvis (just checking to see if you are paying attention!) and so on.

But I bet you don’t know about their unusual love lives: one species which can be observed on muck dives in Lembeh Strait, a large (up to 40cm / 15 inches long!) spearing mantis shrimp, Lysiosquillina maculata, variously called in plain English the ‘zebra’, ‘tiger’ or ‘giant’ mantis shrimp, has a fascinating private life. First of all, they are monogamous, and usually mate for life, a rare trait in the animal kingdom. These creatures can live up to 40 years and one marine biologist is studying a pair which has been together for 20 years. They live together in long (up to 10 meters/30 ft), U-shaped burrows where the female hides underground and the male waits at the entrance for soft prey to pass by such as a fish or a Big Mac. When something tasty comes near, the male will strike out and spear it with its raptorial appendage (scary words for spearing arm) and then considerately bring the takeaway meal to his ‘wife’, letting her eat first. What a gentleman, you’re thinking! Females have much smaller eyes and arms and are essentially ‘barefoot and pregnant’, ill-equipped to hunt or fend for themselves, and therefore dependent on their males for survival. Wait, you say, that’s pretty old-fashioned, where’s the good part?

Well, what if something happens to the male? According to ichthyologist and expert on stomatopods Mark Erdmann, if the male disappears for whatever reason, the female will advertise her availability by making a noise, something like what a cricket does, to attract a new male. According to experts, this is because they don’t yet have Facebook where they can advertise their relationship status. The size of the female determines the particular frequency of the noise and apparently, the bigger the lady, the more desirable she is, because it means she can produce more eggs: size matters for mantis shrimps! So if a male hears this seductive siren ‘song’ and determines that the female is bigger than his current mate, he may in fact leave her to ‘trade up’. This Donald Trump of the underwater world will then shack up with his plus-size new babe, leaving his ex who then must ‘sing’ to attract a new mate. Does she trade in for a younger male? Stay tuned to find out!
Acknowledgements: A special thank you to Mark Erdmann, who told us these fascinating facts during Fish Geek Week at Lembeh Resort.

Article by Lauren Siba (Dive Center Manager)