That Fish Blog – Aquarium Advice and Information

The adaptations developed in the waters of our world are some of the most amazing in existence. From bioluminescence to specialized mouths built to feed on certain foods, the fish and invertebrates living in Earth’s oceans, lakes and streams have some of the most unique traits found anywhere. What is even more interesting is how two life forms that are completely different and unrelated can develop a near identical solution for a problem.

I have always been fascinated by the strange and the odd. From fish that mimic pieces of driftwood like the Chaca chaca to the lobe-finned and air-breathing Polypterus species, I have had the pleasure of keeping many unique fish species. Recently, I received an email from Frank Indiviglio that contained a link to some weird starfish.  After reading it, I immediately saw a parallel to another article that I had read a couple of days earlier about a new fish from Lake Tanganyika. Read More »

Hello, Frank Indiviglio here.  Marine aquarists and divers are well-aware of the mucous “sleeping bags” produced by Parrotfishes and certain Wrasses each night.  It was assumed that these cocoon-like structures discouraged eels, crabs and other nocturnal predators – perhaps the mucous hid the sleeper’s scent, or was bad-tasting or toxic.  A study at Australia’s Queensland University, however, has revealed that the mucous cocoon’s main purpose may be to deter external blood-sucking parasites – the first known example of such a phenomenon.

A Good Reason to Hide

Writing in the November 17, 2010 issue of the journal Royal Society Biology Letters, researchers have established that sleeping Parrotfishes suffer numerous parasite attacks when deprived of their mucous cocoons (I couldn’t determine how they removed the cocoons without waking the fish!).  Parrotfishes with intact cocoons sleep peacefully through the night, and were rarely bitten. Read More »