Nudibranchs Articles

[REEFVETTE]

Does anyone know of any good articles on these little guys...... I want to gather as much info as i can. I want to maybe set up a tank for like one or two..... thanks guys for any info

[Ninong]

Does anyone know of any good articles on these little guys...... I want to gather as much info as i can. I want to maybe set up a tank for like one or two..... thanks guys for any info

There are thousands of different species of nudibranchs and every single one of them is carnivorous. Almost all of them are specialized feeders that prey on just one prey item. Most Dorids, for example, feed on various sponges. Sometimes they will eat several different species of sponge but often times they will eat only a single species. Others specialize on feeding on certain corals, such as the infamous Montipora eating nudibranchs that often plague unsuspecting hobbyists.

Be aware of the fact that the natural lifespan of most nudibranchs is between 12 - 24 months. You will need to know exactly which species of nudibranch you are acquiring and you will need to know exactly what its prey is so that you can provide it. This information in unknown for most of the described species of nudibranchs.

If you do acquire some nudibranchs, be aware of the fact that you have no way of knowing if they have eight weeks or eight months left to live.

The only nudibranch that I can think of offhand that might be beneficial in an aquarium would be Berghia verrucicornis, the Aiptasia eating nudibranch. They are quite small, very expensive and they have a tendency to go over your overflow or otherwise disappear. I have never tried them because I have never had any Aiptasia.

I did try four Elysia crispata sea slugs once to see if they would eat Bryopsis as claimed by many hobbyists. I don't think I had any Bryopsis in my tank because they all died within a few months. They constantly went over the overflow and I had to retrieve them from the sump. They gradually shrank in size until they just faded away. Two of them died accidental deaths and the other two starved to death. These, of course, are NOT nudibranchs in spite of what all of the vendors call them. They are saccoglossan sea slugs. They are usually called "Lettuce Nudibranchs" by most online vendors but this is totally false and misleading. They are NOT nudibranchs. If they were, they wouldn't eat algae.

Dr. Ron Shimek's nudibranch article: http://reefkeeping.com/issues/2002-09/rs/index.htm

P.S. -- Don't overlook the fact that many, if not most, nudibranchs are toxic to some extent. Most exude a toxic slime to fend off predators. In general, marine animals that are very brightly colored with very obvious and striking patterns are toxic. That's why they have aposematic coloration -- to warn off predators. Marine animals that are not toxic often have cryptic coloration to blend into the background. Mandarin dragonets are a very good example of a fish with aposematic coloration. Their bright colors and crazy pattern warn predators that they are definitely not tasty, thanks to their noxious slime coating.