While it can be an amazing experience to dive beneath waves and see creatures on and all around coral reefs, it is also important to remember that there are many marine creatures that live in the substrate. Today we’ll highlight just five such creatures to better inform divers about the fragile environment they enjoy. Some of these creatures go their entire lifetime without leaving the substrate, while others just visit the area for specific purposes. Keep your buoyancy in check and a sharp eye out for these little critters on your next dive!
Garden Eel
The garden eel thrives within the Indo-Pacific and belongs to the conger family of eels. These skittish creatures will poke their heads out slowly above the substrate in order to snatch zooplankton for food, conveying the image of an underwater garden of tall grass. When threatened, they zip back into their burrows in the blink of an eye. While it’s unlikely that you’ll spot one from right above, you may be able to spot a “garden” of them from a bit of a distance if you stay low to the substrate.
Blenny
The blenny is type of small fish that hunts along the substrate in order to satisfy is omnivorous diet. These fish partially conceal themselves inside the substrate to quickly pop up and snatch smaller sea life or vegetation, but they are also just as likely to skulk among reefs or lunge out from an abandoned shell.
Flounder
The flounder is a somewhat intelligent variety of fish. While this creature’s skin has a mottled pattern in order to help it blend in with the seabed, it is also prone to partially burrowing into the ground. Being a species gifted with natural camouflage, the flounder is an ambush predator that favors crustaceans and smaller fish.
Tube Worms
The tube worm is among the most frequently encountered marine creatures that live in the substrate. These normally immobile invertebrates live by tethering themselves to a point beneath the substrate and growing a cylindrical layer of protective rock along the lengths of their bodies. A tube worms feeds by lunging at nearby plankton with their bristles and then dragging them into its stomach like a net.
Tunicates
The tunicate, also called a sea squirt, is another invertebrate similar to the tube worm, but with a great variation of shapes and colors due to a wide-ranging variety of species. Tunicates feed by filtering sea water and subsisting on nutrients within the water.
