Mangrove Wildlife FNQ

Like millions of others, as a kid, I loved exploring rock pools and tidal areas. Everything seemed so bizarre - so alien. It's a fascination that's never left me. So with the afternoon to myself, I wandered down to some mangroves just to see what might be about ... here are a few pics of what I found.

Fiddler crabs are exhausting just to observe! - with their semaphore waving of oversized claws signalling their owners desire to mate or simply marking their territory. Coupled with their scuttling movements and frenetic dashes into burrows at the slightest hint of danger. They are obviously torn between having a feed and not being eaten themselves.

The common name is attributed to the feeding behaviour - the smaller claw is used to pick up and transfer food to their mouth in such a way that it looks a little like the crab is playing its larger claw.

(Uca sp)

Found in mangroves, salt marshes and sandy or muddy beaches of West Africa, the Western Atlantic, the Eastern Pacific and the Indo-Pacific, fiddler crabs are easily recognized by their distinctive asymmetric claws.

Some experts believe that the feeding habits of fiddler crabs play a vital role in the preservation of wetland environments by sifting through the sands, they aerate the substrate and prevent anaerobic conditions.

A larger and far more confident fiddler

It wasn't just fiddlers though - this handsome maroon mangrove crab was quietly sifting through the detritus left by the outgoing tide ...

Perisesarma messa

There were even crabs climbing the mangroves themselves ... (yes, I know there are crabs that climb trees ... but still)

Love the hues and depth of colours!

Could this be a female fiddler crab I wonder?

As the afternoon passed I even witnessed an attempted mugging. These hermit crabs were engaged in an epic struggle with the chap on the left attempting to pull the smaller crustacean out of its home in order to have it for himself - a mugging and a home invasion!. Actually they were quite large and with shell, would easily fill a mans palm.

The battle was still raging when I left, but I have to say - I was rooting for the little guy.

Many species in TNQ - (Clibanarius spp)

... not by the hairs of my errr chelipeds?

If you don't live in a part of the world that supports these next little fellahs - there's a good chance you will have seen them on at least one nature doco. They are the effervescent and incredibly acrobatic mudskippers.

Personally, I can watch them for hours as they splash and squabble along the water's edge. I occasionally wonder what people must think - watching me smiling into the mud for no appreciable reason. But then I remember that everyone's mad, and continue on ...

(Periophthalmus sp)

Note the placement of the eyes - enabling the skippers body to remain almost totally submerged

The ability to breathe through their skin and the lining of their mouth (the mucosa) and throat (the pharynx). This is only possible when the mudskipper is wet, limiting mudskippers to humid habitats. This mode of breathing, similar to that employed by amphibians, is known as cutaneous air breathing.

Another important adaptation that aids breathing while out of water are their enlarged gill chambers, where they retain a bubble of air. These large gill chambers close tightly when the fish is above water, keeping the gills moist, and allowing them to function. They act like a scuba diver's cylinders, and supply oxygen for respiration also while on land.

Digging deep burrows in soft sediments allow the fish to thermoregulate, avoid marine predators during the high tide when the fish and burrow are submerged, and for laying their eggs.

Even when their burrow is submerged, mudskippers maintain an air pocket inside it, allowing them to breathe in low oxygen conditions.

Hermit crabs are big in the pet trade - but please be aware almost every species needs both fresh and salt water to remain healthy, (even if the bloody pet shop tells you otherwise). So if you're thinking of getting one or two - do a little bit of research first. In fact, do that for any animal you are considering making part of your family eh?

Hope you enjoyed the post half as much as I enjoyed creating it.

Take Care