Nautilus at the Steinhart Aquarium

[DWhatley]

I wonder if being overwhelmed lately is common. It was a mental relief to be put on parttime status and now to be layed off (a financial mess though). I am almost caught up so I hope I find something soooooon!

 

[Tintenfisch]

Love the music

 

[asid61]

I went to the Steinhart yesterday to see if the nautiluses were back on exhibit since on my visit two months ago, I saw none. There was a huge 1' cuttlefish there instead, and I thought it was one of the 4" ones that were on exhibit 4 months ago. I could only see 1 nautilus in the tank, though, on this visit. What happened to the other nautiluses (nautilii)? And where is that huge cuttle?

Pretty cool operation! I think a medical on a nautilus is a pretty funny idea, and my mom laughed when I told her about it.

 

[gjbarord]

That's a great idea about Drum and Croaker. Be good to get that info out there to the people who need it the most. I'll send you an email about an additional possibility as well of combining our data for another audience that also needs it.

Good stuff as always Rich!

Greg

 

[Thales]

 

[DWhatley]

I assume that is mating and not consumption but that does bring up a question. So you ever see same species aggression? The ones we have seen kept together have varied in size, something that seems to be a problem with other cephs.

 

[gjbarord]

There have definitely been instances of cannibalism in nautiluses. The usual signs of it are nips along the shell of captive nautiluses and stomach contents of wild nautiluses containing nautiluses. In captivity, I have never observed any problems with the different sized nautiluses in a tank. Right now, we have some very small nautiluses in the same system with larger ones and have not experienced any problems.

Greg

 

[DWhatley]

Greg,
Do you practice the feeding policy that trys to ensure everyone is fed as we saw in Washington? Do the big guys always get the food first? It would make anticdotal sense that an aquarium environment with this arrangement might minimize hunger attacks and it seems to cooralate with some of the group living we see in octopuses as well as the reports on keeping vulgaris in groups in relatively small tanks (predation was noted here but common size and feeding frequency was reported to minimize the problem). It might also be that the nauts inside nauts were cases of scavaging rather than attack. The nipped shells, however, don't suggest just scavaging.

 

[Stauroteuthis]

In that picture (being utterly inexperienced) I can't tell whether they are fighting or mating. Come to think of it, I don't know much of anything about nautilus reproduction. Is there a hectocotylus?

How did this turn out?

 

[Thales]

They are fine - I am assuming mating as there are no wounds. I think the size difference makes it look worse than it is. There is a spadix in the males...I have a pic somewhere.

 

[Stauroteuthis]

That's pretty amazing that you've got breeding a breeding pair of nautilus. It'll be even more great if you get eggs. How many do they usually lay at a time? What kinds of conditions are necessary for breeding nautilus? I honestly wasn't aware until fairly recently that such a thing was even possible in captivity.

 

[Thales]

The last group I worked with laid a lot of eggs, one at a time. This quad (1 male and 3 females) is a new group and have produced no eggs yet. Hopefully, I will have info to share in the near future.

 

[gjbarord]

D: I have always fed nautilus one at a time as a way to monitor their health and ensure all of them are eating. I have not observed any significant cannibalism in captivity so I really do not do anything to try and minimize cannibalism. Of course, if I did start seeing cannibalism I would most likely increase the amount of food being fed.

Stauroteuthis: As Rich said, nautilus possess a spadix which is a modification of several smaller tentacles forming on larger tentacle on the side of the beak area. I may be mistaken, but I do not believe that the exact function of the spadix is known?? It may simply move the female's tentacles aside to allow spermatophore transfer. I just can't recall any papers specifically on the subject.

Greg