Baby Starfish????

[ouccmich]

Hi everyone!

Happy weekend! Anyways, as I posted earlier about my mandarin and weather or not I had enough food for him avaiable and then found tons of amphipods and tonight I had a break out in my tank of thousands of copepods! I'm not sure if this is a one time thing, but I've never had so many before! It's crazy. Of course, my mandarin is sleeping when she should be eating. Not sure on how to "train" her to eat at night. I did find her sleeping right next to a clump of them on the sand. Maybe she ate her fill and went to sleep????

Also, tonight I saw AT LEAST 20 baby starfish!!! Has anyone had this happen and if so have they ever had any successfully make it to adulthood (before getting eaten?). They are all really small, but one is a pretty substantial size for a baby and is starting to show some color. I have two sandsifting starfishes that were mating like crazy a month or so ago...possible from them? My green brittle and red serpent tend to stick to opposite sides of the tank. Anyone have any thoughts on the baby starfish??? Just curious!!! Please respond if you have any thought, any at all.............have a GREAT weekend. It's spring break for me....never needed a break from class in my life. This semester is brutal!

[lizardarm]

what color are the starfish?
if they are a whiteish color, they may not be babies. there are really small varieties of stars that we tend to find in the top layer of sand, or under a piece of live rock if you lift it up. the ones in my tank are white, some with thin dark bands about their arms.
as far as the mandarin, it's got its game figured out. at night the pods are all awake and alert, makes for harder hunting. so she waits until daylight when the pods are all sleeping to pick them off. no training required

[TheReefer12]

The starfish you have found are probably hitch hikers. Most likely came on a piece of live rock or were in the sand (if you are using live sand). Most of the starfish are probably sandsifters, but if you do see some coloration on some you may be on to something.

Brian

[ouccmich]

Thanks! I went to another LFS that was in MI today and they had HUGE mandarins for about half the price I paid AND their mandarins did not look as thin as mine. Hopefully my mandarin is smart and will start eating more, because I KNOW I've got copepods in the tank....

Anyways, the starfish are WHITE. They almost look like mini brittle stars (their arms have the brittle appearance) but some are bigger and have grey centers. They all have 5 arms (not 6 like I've seen in past posts). I haven't added any new LR or any sand in a while....about a month or so and the starfish are intermixed in all of my LR...mostly near the LR that's closest to the surface. They are very cool to watch, but you guys are right. Not sure if they are "mini stars" or "baby starfish" or what they are.....

[Metalhead]

I have them too, came with some pods. They seem to reproduce in the tank at least mine do. I think they will only get as large as a dime or a bit larger from end to end- I have had them for about 8 months and that is all the bigger any of them has grown. I believe they are a mini brittle but none of mine have grey centers. I had only seen one when I first introduced them in to the tank and only a few times since but now I can locate them in the cheato micro algae with the pods and a few other places where they hang out. I just recently witnessed my orange leg hermit crab releasing a batch of babies in to the system. That was neat!

[tdwyatt]

Heh! Good find for you!

Many folks PAY big money to have the mini-brittle sea stars. check the site at Indo-Pacific, they have them for sale. Great detritivores, they come in several colors, and are fissiparous, so they should grow their numbers to fit the food availability.


Get rid of the sandsifting sea stars if you want to keep your Mandarin, as these sea stars are sifting for food in the top layer of the sand, and this is one of the breeding areas of your amphopod and copepod populations (as well as algal beds or macroalgae mats) where the sea stars will eat the young forms of these lower members of the food chain.


Take the sand sifting sea stars back to the LFS and see if they'll swap them for a pair of Holothurians to maintain your sand bed.

HTH

[WilyGuy]

Originally Posted by tdwyatt

Take the sand sifting sea stars back to the LFS and see if they'll swap them for a pair of Holothurians to maintain your sand bed.
HTH

Tom, can you put that one in English for the rest of us? I did a search and came up with something that looked like Nudibranches?

[tdwyatt]

Originally Posted by WilyGuy

Tom, can you put that one in English for the rest of us? I did a search and came up with something that looked like Nudibranches?

They are the sand ingesting species of sea cucumbers that look pretty much like cat turds in your sand bed (don't let the cat see!) Holothurians are responsible for converting a good bit of the autotrophic production and nutrient assimilation of the sand bed into biomass (the body of the sea cuke) that results from their ingestiion of the sand bed, digestion of the biofilm (and its bacteria and algae) off the sand, and pooping out nice clean sand. They only perturbate the top 5mm or so of the sand bed, but by doing so will keep the sand bed relatively clean of settling detritus and biological film accumulations resulting form succession within the mini-ecosystem of the sand's biofilm. Lots of information out there, look for authors like Yuri Sorokin, Tom (TF) Goreau, JA Hansen, GA Skilleter, etc in relation to changes in bacterial populations in the benthos as a result of grazing by Holothurians, clams, microbenthic copepods (especially harpaticoids), nematodes, protozoans, and turbellarians. Sorokin's work in particular established the large role that Holothurians play in this process using radiolabled bacteria (see Sorokin, Yuri I, (1978) Arch Hydrobiol 83: 281-323. ) This is another piece of supporting evidence for increasing biodiversity in benthic environments to maintain some sense of a food chain within the benthos. This is not to say that they will be maintenance-free by any means, just that a long involved food chain including top-down predation/grazing handles both carbon and related nutrient sequestering and compartmentalization within mature and well-maintained sand beds.


These cukes are not the brightly colored ones that are often filter feeders farther up in the water column, rather the dull, so-so denizns of the bottom that extend their oral tentacles to feed on bacterial slimes and cast off detritual materials...




...pretty much like attorneys.