Flashback Friday: Octopus hatchlings at the Steinhart Aquarium
About Flashback Fridays: Every Friday, Advanced Aquarist will repost a blog article from this week one year ago. With all the content we publish, we want to share the timeless and interesting articles for our new readers as well as regulars who may have missed the original blog article.
In January 2011, The Steinhart Aquarium in the California Academy of Sciences received a Caribbean Octopus 'vulgaris' for display. It quickly took up residence inside a glass bottle, which is exactly what I wanted it to do so it would always be visible to guests. Just as quickly, it moved back under some rock and started denning, and my heart sank because we knew it was a she, and the she had laid eggs. While eggs being laid in captivity is generally an exciting event, this particular species, like many but not all octopus, stops eating after it lays eggs and dies soon after they hatch which tends to put a damper on joyous hooplah. Even worse, this species is 'small egged' meaning it produces large numbers of very small planktonic 'paralarvae' which are notoriously difficult to feed and raise. So, we tilted the rock where the eggs were laid to make them visible to the public (but in a high flow area so they would continue to develop), and the adult octopus moved back into the bottle making for an all round cool and educational display of something most people don't get to see. The unexpected icing on the cake was catching the hatching of the eggs from start to finish, and also being able to get much of it on video. Although we weren't able to raise the hatchlings to maturity, something few have done (if at all), we were able to keep them alive for 26 days, and the image of a waterfall of tiny octopus paralarve flowing up from the egg mass to the surface of the water is something I don’t think we will ever forget.
Nuts and bolts
- Caribbean Octopus 'vulgaris' (there are several Octopus that use the species name vulgaris which is why its in quotes)
- Roughly 3 weeks between eggs being laid and eggs hatching.
- Hatching occurred at 9 am.
- When I turned off the flow to better witness the hatching, the female octopus quickly left her bottle den, agitated the eggs presumably to help the hatch, and is now sadly protecting the space where the eggs were.
- The female many hatchlings will be on display at the Steinhart Aquarium in the California Academy of Sciences until they can no longer be displayed.
- The hatchlings are 1-2 mm in length.
- There are 1000's of them.
- The hatchings are in a Kreisel tank and being offered 24 hour Artemia, which the literature suggests is the correct size to be eaten by the little octos, along with rotifers which are smaller to cover all the bases we can reasonably cover.
- A previous batch of hatchlings from my home had individual paralarvae survive until day 9, some of these survived until day 26
- The Caribbean Octopus 'vulgaris' seems to be a smaller species than its larger Mediterranean Octopus vulgaris cousins
- For more information on keeping and breeding cephalopods check out www.TOMNO.com.
- A very posed photo in a drop of water
- The lines in the upper corner are millimeters.
- The female in her bottle. Note she has plugged the opening with rubble. After I disturbed her den and eggs, she moved into the bottle and laid 4 or 5 additional strands of eggs in the bottle.