Tuesday, August 20, 2013

Festoons

 
Are you curious?  Do you have a guess?


Here's a closer view:


This may be challenging because these embryos are still very young.  They're 36 days old, but are only about one third of the way through their development.  Each one is ~3 mm long.

In the photo below, note the very large eye — the orange pigment is the retina.  And look for the tiny rounded buds — although there are only four in view, there are eight in total (that's a big hint!).


These are the embryos of a Red Octopus (Octopus rubescens)The rounded buds mentioned above are developing arms.  And the large, opaque, balloon-like structure taking up a significant portion of the space inside each capsule is the yolk.  At the water temperatures found in Bodega Bay, we believe it will take over 100 days for them to fully develop and hatch.

Eric was taking care of this octopus in an aquarium during his summer class.  One morning she was behaving differently and he discovered that she had laid eggs!  Red Octopuses produce multiple festoons or strings each containing dozens of small egg capsules.  I tried to photograph her protecting her eggs in the aquarium (see below).  Look for the tiny white eggs being covered by the octopus.  [The octopus attached the eggs so that they were hanging down from the roof of a large empty mussel shell.]


The next picture shows a close-up of the eggs.  They look like tiny grains of rice.


Because this octopus had been kept alone, we weren't sure if the eggs were fertile.  So after a month we decided that we should look at a few of the eggs to see if they were developing.  It was very exciting to discover the little embryos inside!  We'll continue to let the octopus protect her eggs (tremendous dedication on her part!), and we'll maintain this small cluster of eggs in seawater and document their development over time.  Stay tuned for updates, hopefully until hatching in mid-late October!

4 comments:

  1. Thanks for updating on this! I remember Eric discovering this amidst our SSI class. Eager to see how all these little baby octopuses turn out. He had mentioned that often the mother octopus will die, because she protects her babies so ardently that she doesn't feed herself. It'll be interesting to follow how the whole family does!

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  2. Yes, we've read conflicting reports about whether the female feeds while caring for the eggs. We can add one data point -- this female octopus is eating regularly. She particularly likes small crabs!

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  3. It's wonderful for the Tidepool Education docents working with State Parks to be able to follow the development of animals we see with students on their field trips. Thank you for this!

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  4. I was very fortunate that I saw this with my very own eyes in person and presented by Jackie and Eric! What a day!

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