Mantis population density?

[hobobob]

I wonder what the population density of Mantis shrimp in the wild. Let's say the Gulf of Mexico.

I just stocked my tank with rock and I've seen two already. One is Neon green and the other is brownish purple. I wonder if there might be even more yet to show themselves.

It seems that most people get at least one with their rock. How many of tthem critters are down there?

 

[Gonodactylus]

Density is highly variable with species, habitat, etc. Also, what size are we talking about. There can be dozens of juveniles per square meter, but only one or two adults.

I've conducted lots of surveys and typical data for density are:

In Panama (Galeta reef flat, 1 - 5 per meter squared Neogonodactylus bredini

Key Largo (Thalassia beds, 3 m, 3 per meter squared, Neogonodactylus

wennerae and N. oerstedii


On the other hand, if you are interested in stomatopods per piece of LR, the data are a lot more variable depending on the abundance of rock, etc.


For example, at Galeta if we look at rocks smaller than a basket ball, the numbers range from 0-27, median 3. In Hawaii at Kaneohe Bay, 0-6, median 2 (G. falcatus). At Lizard Island, LR from 18 m, 0-4, median (6 species)

Roy

 

[hobobob]

Roy,

Thanks for the reply. This is quite an incredible forum you oversee. My desire to keep a friendly reef with lots of cleaner critters has morphed into a need to keep these fascinating animals.

I'll have to figure a way to balance it out.

Can you, in general terms, define a juvenile? I'm sure that size wise, it will vary from species to species. My guess is that my hitchhikers are members of Neogonodactylus. At what size are they considered adults?

Do you have any recommended reading on Stomatopods? They seem to compete with slime molds to me as far as subjects worthy of study.

Thanks again for your time. You do this forum a great service.

bob

 

[Gonodactylus]

It's not my forum. I just try to add a bit of information now and then.

As a rule of thumb, most stomatopods become reproductive at around 50% maximum body size. Take G. smithii. They reach a maximum body size of around 85-90 mm and you typically don't find reproductive females under 45 mm.

N. oerstedii gets to around 65 mm and first reproduction is around 40 mm.

N. bredini gets to around 60 mm and first reproduction is around 27 (rarely).

So you can see some variation but if you guess half maximum body length, you won't be far off.

Roy

Roy