Sepiolid eggs

[Jean]

Hi

Would anyone know the gestation of Sepioloidea pacifica eggs??? (Steve any ideas??) we've had some laid in our public aquarium and we'd like to know the approx hatch date so we can keep an eye on them. They're on the downpipe of our seahorse exhibit and we don't want them becoming a meal for the horses!

Cheers

J

 

[Steve O'Shea]

Hi Jean. All I can find is E.L. Hurst's BSc (Hons) thesis from the University of Otago, although I can't find a clear reference/description therein as to how long it takes for the eggs to hatch.

Hurst says that eggs are found throughout the year, but that females (in the laboratory) laid them between the months of November and March (~austral summer). 11 females deposited eggs between 27 November and 11 December, and the first larvae hatched on 12 February. If I read the thesis cover to cover there might be mention somewhere of how long it took for the eggs to hatch, but it's not obvious.

The embryos are staged and illustrated, so perhaps a look at one or two might help you determine when they'll hatch (sounds barbaric, but you might need to do it to save the majority).

Cheers
O

 

[Jean]

Thanks Steve,

We have the Hurst thesis so I'll have a look before I take the step of dissecting an egg! I'll keep you posted as to what happens!

J

 

[Jean]

I've looked at the Hurst thesis, no mention of gestation........but I haven't dissected an egg yet! Really not sure I want to do that, I'd probably get lynched by the rest of the staff

Anyhow we now have three batches of sepiolid eggs and the first lot laid have eye spots apparent So we are keeping a much closer eye on them as we have in the same tank, a number of seahorses, 3 baby sharks (patch, splotch and blotch ) and a baby skate, all of whom would find newly hatched cephs rather tasty!!

J

 

[perke]

Come on Jean live a little I'll even help you in the act of mutilation . Just tell me when and I'll be there.

 

[Clem]

Jean,

Does the tank with the egg-clutches in it have a day/night cycle? Don't know about S. pacifica, but Euprymna scolopes egg-hatching is said to be retarded by too much light. (I only know this because of the Bobtail squid article I read last night.)

Good luck with the squid hatchery.

Clem

 

[Jean]

Come on Jean live a little I'll even help you in the act of mutilation . Just tell me when and I'll be there.

Fine, Kerry but YOU get to tell Praneeta & Trudie!!!!!!

Does the tank with the egg-clutches in it have a day/night cycle

Clem, Yep The whole aquarium does, lights go on ~8.30-9.30am and go off between 4.30 & 5.30 (depending on how fast we get the cleaning done!)

Cheers
J

 

[perke]

We'll just tell um that we missplaced some while cleaning. Otherwise you can always help me in distruction of squid!

 

[Jean]

We'll just tell um that we missplaced some while cleaning. Otherwise you can always help me in distruction of squid!

Trudies probably already named each and every one!!! I may have to destroy your squid

J