The wait is over, and the numbers are in; it’s time to explore our findings from the Linckia data collection survey!
We received 16 submissions, each with valuable information for this article. I want to extend a massive thank you to everyone who took the time to fill out the form, and especially to those of you who went above and beyond with photos (shown in the article!) and in-depth info.
Let’s dig in.
“Link the Star Fish”, one of the few who ate prepared foods. Credit to anonymous respondent.
First, according to our data, a generalized lifespan of approximately 1.5 to 2 years seems to be the limit, though a few reefers have reported that they live up to 5 years and counting. Most responses say that their current stars are still alive but have lost other stars around the same age. This aligns well with another online consensus that the star has enough ‘fat reserves’ to survive a year or two before it burns out.
Thirteen respondents reported feeding behaviors, in most cases consuming the enigmatic ‘biofilm’ while others consuming Aquilonastra stars or algae on the glass. Two users reported hand-feeding, one of which was L. laevigata and one of which was a red “Linckia.” The blue star was reported feeding on the purple photosynthetic sponge (Collospongia sp), Yellow finger sponge (Axinella polycapella), and Yellow ball sponge (Cinachyrella alloclada) and was hand-fed Masstick stuck to frag plugs twice per week. The red “Linckia” was reported to eat various liquid foods, including oyster eggs, PNS bacteria, live phytoplankton, and oil films from the water’s surface. All three hand-fed stars were still alive at the time of data collection.
The remaining three respondents did not report any feeding behaviors.
Large blue L. laevigata. Credit Juan P.
Out of every response, feeding or not, not a single respondent reported measurable growth; in fact, half of the reactions that recorded feeding still cataloged a noticeable decline in general fatness and health over their time in captivity. A notable exception is our Masstick and sponge eater, which was reported to have maintained, if not increased, their fullness over a long period. Still, no radial growth was noticed.
A correlation between the reports of long-term care (3+ years) and the general size of the aquarium could be made. However, very few respondents gave information on their aquarium setup (more on this later). Even still, the three oldest reported stars (all 3+ years old) were said to have been in “dirty” tanks, over 100 gallons each, with plentiful algae growth and biological accumulation. One in particular was a ‘hospital system’ reportedly run like a refugium.
Red “Linckia”. Credit Ricardo M.
In the end, I did not collect as much data as I would have liked, but this still helped us to paint a picture of what to do and not to do with these animals in the long term. Our best-reported cases and longest-reported lifespans are from people who reported ‘dirty’ tanks or have trained them onto food. For L. laevigata, sponges are the apparent preference. Despite this, nobody has managed to get one to grow visibly, even though most of the specimens in the hobby are collected relatively small by species standards (stars over 12″ in diameter are common in the wild!).
After organizing this data, I recognized some faults with the survey, the most pressing of which is the total lack of requested environmental information. If I had asked for parameters, co-habitants, dry or live rock, and tank size, this data would be more useful for our purposes. Of the 16 respondents, 4 reported minor details about habitat.
Another data set that could have been very valuable would be the origin. This was an optional field on the form; however, only two participants knew where their stars came from. It’s not an easily accessible data point, so that may be wishful thinking.
We still have much to learn about these incredible animals before we can confidently keep them in our aquaria. Here’s to more experimentation, citizen science, and hopefully, another chapter in this series, hoping to crack the code to the forbidden fruit that is Linckia.
The full results can be viewed here:
The red “Linckia” doesn’t belong to that genus. Also, you simply need a bigger sample size for meaningful statistics…