Sick Feather Star

[Nemain]

I bought a feather star about a month ago. Feed twice daily.

He *appeared* to be happy. Then a couple of days ago, he lost his feathery legs all over the place. It is like they were snipped off with scissors. The legs are roaming around the tank o_O and feather didn't eat yesterday, and was almost non responsive. I had to blast him with the turkey baster to see if he was still alive. He is out and sitting in a High flow area with his short little feathers.

Any ideas?

Thanks,

beth

[Bert]

crinoids are virtually impssible to keep in captivity. Once they loose thier arms they will die, because they need thier arms to feed. I am pasting a part of an article about them.

SNIP
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There are about 600 species of modern crinoids, and about two-thirds of them are comatulids. Feather stars are common reef inhabitants and are particularly diverse in the Indo-Pacific, where they are found in relatively high densities, but they are also found commonly in the Caribbean, although there are only a few species found there. Although uncommon on the Atlantic coast of North America, one species, Florometra serratissima, is plentiful in spots along the Pacific Coast where aggregations of several thousand can sometimes be found, particularly along the coast of British Columbia.


Generally coral-reef crinoids are moderate in size organisms, with a span across the extended arms that ranges from 30 to 60 cm. They hang on to various reef substrata with their cirri and extend their arms out in the current to catch plankton. They are good echinoderms and possess the water-vascular system and tube feet that are characteristic of this phylum; however, unlike most other echinoderms, they do not use the tube feet for locomotion. If they need to move they generally do so slowly, by the deliberate grasping of the substrate by the cirri. If they need to move more rapidly, perhaps to escape a predator, they release the grip of the cirri and, using a particularly beautiful undulatory motion of the arms, they propel themselves up into the water, swimming for short distances.
This swimming is undirected and results in random movement, as they lack eyes to see where they are going. Crinoids, like all other echinoderms, lack even a rudimentary brain, and the nervous system is difficult to see. Nonetheless, they have good sensory capabilities, with millions of small sensory cells located throughout there skin. How the information that they receive is processed, and utilized, however, remains unclear.

Feeding - The Reason for Reef-keepers' Problems.

In a reef-aquarium, crinoids often seem to behave normally, at least for a while. Then, almost invariably, they gradually disintegrate, from the tips of the arms inward, until they finally die. These animals are simply starving to death. Maintenance of many suspension-feeding organisms is difficult in reef aquaria. All suspension-feeding animals, ranging from feather-duster worms to flame scallops to tunicates have specific requirements for their food. In some instances, the hobbyist is able to provide either the appropriate food or an acceptable analogue. In most cases, however, this is not the case and such animals often perish in our systems. Crinoids have a peculiar feeding mechanism, and seem exceptionally "picky" about their food. Consequently, they are exceptionally difficult to maintain in captivity.

Feather-stars feed by capturing minute particles of planktonic food. The natural diets have been investigated in only in a few species, and in these most of the food seems to consist of invertebrate larvae, microscopic animals, and protozoans. As is common in so many filter-feeding organisms, they utilize a combination of cilia and mucus to assist in either food capture or movement of the food to the mouth.

Ciliary-mucous suspension-feeding is probably the most widespread feeding type in the marine environment; almost all phyla have some representatives that feed in this manner, and many species only can feed in this way. Mucus is secreted by gland cells, and cilia are used to move this mucus. Mucus is often taken for granted, but this material is so ubiquitous, that it can truly be said that without mucus, life itself would not be possible... Chemically mucuses are called glycoproteins, or chemical combinations of sugars and proteins. Generally mucuses are sticky and viscous, although the latter property can often be varied by varying the ph of the medium.

Cilia are small, undulating processes located on the surfaces of cells. Although they are often called hair-like, they are in point of fact, many thousands of times smaller than a human hair. Their motion results from the movement of slender protein fibrils located in them. In feather stars and many other ciliary-mucous filter feeding organisms, cilia can be found lining depressions of the body called food grooves. Mucus is secreted by the glandular cells lining the food grooves and moves in flowing stream toward the mouth, with the movement of the mucus due directly to the underlying cilia.

The food transport system of the crinoids extends out on to the arms, or the "feathers," of the feather star. It subdivides and continues out into the lateral small projections off the main arm and consists of a mucous-filled ciliated food groove which connects all the way to from the finest arm branch to the mouth on the upper surface of the body. Out on the fine branches, or pinnules, of each arm, the food groove has a row of tube feet on each side of it.


Close up of the rays of a tropical crinoid, the tube feet are visible extending upward from some of the pinnules or side branches of the rays
Crinoids utilize their tube feet in a unique feeding method to catch their food. In all other echinoderms, each tube foot works independently of its neighbors and is used in locomotion. Crinoid tube feet neither work as independent units nor are they used in locomotion. Rather they are used only for feeding, and they work as groups of six, divided into two groups of three tube feet each, on opposite sides of the food groove. These tube feet extend directly up from the animal's surface into the water.
Each of the groups of three tube-feet consists of a long, a medium, and a short tube foot. Each individual tube foot has a different feeding function. When a long tube foot is hit by an acceptable food item (generally a larva or a ciliate), it flicks, knocking the item toward the other side of the tube foot group. The middle tube foot on the other side also flexes or flicks knocking the item toward the groove and finally, the small tube foot on the original side flexes to knock the item into the food groove, where it is conveyed to the mouth by the sticky mucus. All six tube feet work together to ensure that food particles get knocked down into the groove.

This active feeding method is significantly different from most other suspension-feeding organisms which passively filter food from the water and then sort it somehow after it is collected. Crinoids can be considered to make an active choice to feed on each particle that impacts against a tube foot. Presumably, these choices are made based on the particle size, density, and chemical composition or flavor. In any case, however, it means that these animals can be exceptionally selective in their choice of food.


A tropical diurnal feather star from the shallow waters of Palau.
The selectivity of the feeding process ensures that the animal gets the maximum benefit for the minimum expenditure of energy. However, it also means that an aquarist who wishes to maintain these beautiful animals has to provide a food that passes all of the crinoid's criteria for food. And, it appears in most cases, this may well be impossible. Unlike the other suspension feeders, which can utilize substitute food, crinoids generally do not even recognize the substitutes as food.
There may be a solution to this problem, however. Culturing of microplanktonic organisms such as rotifers might provide a useable food source for at least some of the crinoids. Additionally, annelid, bivalve, and gastropod larvae are available commercially for industrial use in aquaculture and for environmental bioassays. These are temperate or subtropical larvae that might be acceptable substitutes for tropical species that are eaten by crinoids. These larvae would also be of benefit to many other reef organisms that feed on microplankton, such as small-polyp scleractinian corals. Unfortunately, with the exception of rotifers, none of these other microplanktonic organisms are accessible to the average hobbyist.
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SNIP

Sorry about the loss, they are far too beautiful for many to resist

Bert

[Nemain]

I had read that before, but ... I listened to the LFS, said that twice a day feedings with phyto would be ok. Silly me. So what to do now? let it die? *cringe*

Beth

[bulletsworld]

Did you get that guy from AI? I think I remember looking at one there and asking what it ate too. It was so beautiful! Never seen anything like it.

So sorry to hear. What a stressful hobby at times hey. Sorry :frown:

[Bert]

I think short of injecting food directly into it's stomach, there isn't much one can do. I saw those 2 feather stars at AI. I wonder if the scarlet red one has passed on as well, it was stunning.

Bert

[Nemain]

They truly are =( I feel terrible for it.

I have emailed them and asked for advice, I hope they have some for me =(

Beth

[Quinn]

I believe Bev continues to successfully maintain hers. I wonder if the issue here is sensitivity to handling, because I believe Bev has also been feeding hers some sort of phytoplankton, and given that yours died so quickly and lost legs in the process, perhaps it was just sensitive. Still, probably an animal that should remain in the ocean... :neutral: