Thoughts on Vitamin D

[Kat]

Kat yes I'd love to get a data collection/survey project started. After work today I plan to put out a "feeler" post to get some feedback on what infotthe community thinks should be included, how best to collect the info, etc.

Great! I'm not super active on the forum these days, so please let me know when and where.

[wodesorel]

So do we have definitive documentation that Es fight more or lead a less harmonious existence with eachother in the wild than PPs or other species?

This is definitely proof to me:

Free-for-all, kill your neighbor for shell:
http://newscenter.berkeley.edu/2012/10/ ... neighbors/

Organized, oh hey, I'll get a bigger home and so will you:
http://ase.tufts.edu/biology/labs/lewis ... tCrabs.htm

[fraksocks]

Ok so what those two articles illustrate to me is that perhaps Es are less ideal for captivity. Unless someone has kept Es of a wide variety of sizes for a long time they are unlikely to have enough of the preferred pre-modified shells for each E (since it the most likely way to aquire a pre-modified shell is by purchasing a crab that is still in it's native shell). The condition of not having enough of the preferred pre-modified shells may cause larger Es, who per the first article are less like to be willing to modify their own shells, to target other crabs in an effort to obtain a shell that has the possibility of being pre-modified. So while Es may be more likely to have "shell envy" the fact that they are constantly killing their tank mates may in fact not be their natural way of being (the article didn't state that such E shell fight chains ended in severe injury or immediate death) but a condition caused by stress (not having access to their preferred shell types) in captivity.

[Eugooglizer]

This is definitely proof to me:

Free-for-all, kill your neighbor for shell:
http://newscenter.berkeley.edu/2012/10/ ... neighbors/

Organized, oh hey, I'll get a bigger home and so will you:
http://ase.tufts.edu/biology/labs/lewis ... tCrabs.htm

I'm not seeing where either of those show any proof that Es "fight more or lead a less harmonious existence with each other in the wild than PPs or other species". We already know that in the wild there's going to be competition for various resources with shells being one of the most valuable to survival as well as there being a huge deficit of shells in many of the areas hermit crabs occupy. The first link used observations done on a group of compressus to illustrate how the "social" behavior of hermit crabs is actually more of an aberration in a "typically solitary animal" in order to acquire an important resource (in this case shells). No similar studies were done on other species of hermit crabs and nowhere does the article imply that this behavior is specific to Es, just that this is a behavior specific to terrestrial hermit crabs in general. The second link also talks about shell competition and "shell chains" but very limited information is given as to their "study" except for that is was done with c. clypeatus....PPs.

[Eugooglizer]

Ok so what those two articles illustrate to me is that perhaps Es are less ideal for captivity. Unless someone has kept Es of a wide variety of sizes for a long time they are unlikely to have enough of the preferred pre-modified shells for each E (since it the most likely way to aquire a pre-modified shell is by purchasing a crab that is still in it's native shell). The condition of not having enough of the preferred pre-modified shells may cause larger Es, who per the first article are less like to be willing to modify their own shells, to target other crabs in an effort to obtain a shell that has the possibility of being pre-modified. So while Es may be more likely to have "shell envy" the fact that they are constantly killing their tank mates may in fact not be their natural way of being (the article didn't state that such E shell fight chains ended in severe injury or immediate death) but a condition caused by stress (not having access to their preferred shell types) in captivity.

I have been keeping Es, along with PPs, since I very first started keeping hermit crabs. I currently have 9 Es ranging in size from tiny to large. I have never had an E kill a tank mate of any species (for me that would include Es, PPs, Indos, and Straws), nor have I ever had a crab of any species kill a tank mate. I obviously don't expect that to be accepted as "proof" that aggressive behaviors and deaths due to those behaviors don't occur in captivity--very obviously they do according to the experiences of some keepers. But there are also other keepers besides me who own Es that live either in a species-specific tank or a community one and have never had an instance of the Es killing a tank mate. There have also been quite a few reports from keepers of violas that they're much more aggressive than other species and there's also no shortage of owners reporting supposed "rogue/killer" PPs. Just some thoughts.

[wodesorel]

How many years was it in total though? Your adoption post stated you went several years without hermit crabs, so this new batch you've only had for a couple of years, right? What happened to the previous Es?

[Eugooglizer]

You're right, I did take a break from keeping hermit crabs. I had my first group for approximately a year and they were rehomed to someone local. I don't know that all the Es in that group didn't start killing everyone off after they were rehomed, I just know that it did not happen with me. Es were the first species that I got to start my current colony meaning that there are 3 which I've now had for a year, others a bit less, I added the last couple earlier this year. So yes, my experience with them as of right now is limited to 1 yr when it comes to total time they have been in my care. Again, I know that doesn't "prove" anything, but I can say that my Es didn't come to me already "aggressive" as has apparently been the case with others. But just as my own limited experience doesn't mean much in itself when it comes to proving anything either way, neither did either of the links I read as far as Es being any more aggressive than other species of terrestrial hermit crabs when it comes to competing for resources (in this case shells).

[kuza]

the links did mention that PP's make shell chains where E's outright fight for every shell they get/take.

And I have lots of E's that aren't aggressive, and some that are. So it may even be where the specific E's are harvested as well.

[zippity]

Nm

[HoD4WC]

This concerns me because being an Ohian *I* am extremely deficient in Vitamin D, as is most everyone I know that lives in this state... and even though I've got a UVB light on my hermies, it sits on a glass lens..and someone here said that UVB doesn't penetrate glass? So how much vitamin D is proper supplementation? Is it sold in powdered form like calcium?

[CallaLily]

even though I've got a UVB light on my hermies, it sits on a glass lens..and someone here said that UVB doesn't penetrate glass? So how much vitamin D is proper supplementation? Is it sold in powdered form like calcium?

Glass will block out UVB completely, from my understanding. Screening will block out some.
Calcium plus Vit D is sold in powder form in the reptile section of pet stores. You could also look up more natural sources of Vit D (fish, egg yolk, liver - I think are some examples) to offer to your crabs.

[Knibitz]

Not to necro a super old thread, but I'm curious - since this post - how are people managing Vitamin D?

I never did until I got a leopard gecko years ago and started to cross share her food with them (worms/crickets she didn't eat)
Since my gecko is now passed, I've still been using her calcium supplement as a duster for the daily crab meals. But this has only been going on for a few months and I don't think long enough for me to see any effects one way or another.

Vitamin D infused calcium was actually a "not-to-buy" in the leopard gecko world. Apparently it was improperly balanced and leaving it out in a dish could lead to a Vitamin D OD.
Calcium w/ Vitamin D was recommended as a food duster - only.
I'm not sure if the OD worry is as high in crabs as it sounds like they have a higher requirement.

[hermitcrab101]

Not to necro a super old thread, but I'm curious - since this post - how are people managing Vitamin D?

I use both UVA and UVB lights in my tank. I also add a calcium/D3 supplement to my crabs meals.