Posts in Category: Box of Slugs
Baby slug video
Things are moving along, but nothing horribly exciting. Veligers are hatching and sluglets are settling. The brood from 10/30/14 has been rather successful, with a lot of baby slugs climbing out of their shells. I will feel better when I see rhinophores sticking out of their heads and chloroplasts in their bellies, hiopefully by the weekend. Meantime, here is one of the cohort climbing on a Bryopsis branch.
Slug and Pony Show!
Not much else to say, really.
Elysia & 2 day-old seahorse
They may be getting a little more color. I only see one or two at a time. Not sure if it’s a survival issue, or they are just deep in the Bryopsis jungle most of the time.
2 day-old pony.
Baby Ponies!
What is the only thing smaller and cuter than a dwarf seahorse? A baby dwarf seahorse! One of the males has been looking rather pregnant of late, and yesterday was the due date.
The babies are extremely small and pale, and for some reason the camera does not like to focus on them.
Newborn H. zosterae 11/18/14
Newborn H. zosterae, adults in background 11/18/14
It’s hard not to think the adults look proud, even though they are really pretty indifferent to the little guys and the male below is probably not the father of this brood.
Female (probably mom) and male (probably not dad) 11/18/14
The male below is likely to be the father, and seems to have a few more in the pouch.
Probably mom and dad 11/18/14
What a difference 5 days makes
Because the age of the eggs collected in the previous post is known with some precision, it was a good opportunity to document the time course of development. On day one, the embryos looked like balls of stuff, and did not move much. Below is a video of the eggs, but it may as well be a still.
However, within 5 days, things have really started to get moving. The embryos are starting to look like little veligers, and are spinning in their eggshells constantly. They still have at least 10 days before they hatch, so it seems like a bit of a waste of energy, but it may serve some purpose.
Next Batch, Known Timepoint
Almost always, egg masses appear sometime after I leave at night and before I return the next morning. I was lucky with this batch, because Mom seemed to be doing something on one of their favorite egg-deposition plants.
E. clarki laying eggs 11/12/14
You should be able to see the egg mass underneath her as it is being deposited. The eggs to the right are the remains of an earlier mass that should be close to hatching.
Next morning, there it was in all its glory.
Egg mass laid 11/12/14
It’s a good one to collect for timing of development. So, here’s what they look like on day 1. Balls of cells and yolk, as far as I can tell.
1 day-old embryos 11/13/14
LED Upgrade
Things are moving along. More veligers have metamorphosed into sluglets, and they appear to be feeding and growing. Come back soon for photos.
Box of Slugs and Bryopsis Growout 11/9/14
I squeezed in a little time to upgrade the setup over the past week. Improvement 1 is the 10 gallon dedicated Bryopsis growout tank on the lower level. The new Evergrow S2 LED lights are supposed to have the optimal spectrum for macroalgae growth (hence the reddishness of the light).
Improvement 2 is the replacement of the ancient compact fluorescent fixture on the Box of Slugs with an Evergrow d2040. Nice little unit, with controls for the blue and white channels. Made a quick and dirty frame from angle aluminum to raise it up to light more of the tank. Still could use a bit more spread.
Next steps include a more controlled environment for hatching and a system for larval growout. As always, stay tuned.
Sluglets have arrived!
I know you are still eagerly awaiting photos and videos of the developing embryos, but this is just too cool not to post immediately. The eggs I collected October 25 (laid the 18th or 19th) started hatching this weekend. I always thought veligers hovered about in a stately manner, but they really zoom around like radio-controlled helicopters. The video below is pretty awful, but gives a sense of how they move.
Even more exciting is that some of them have settled,like this little one, who still has her shell.
Veliger crawling on Bryopsis.
It gets even better. A few have shed their shells and started to crawl around.
Larva crawling in dish 11/6/14
There has certainly been a lot of mortality, and I am trying to figure out how to keep a large proportion of the veligers from getting stuck at the surface. I have also learned that some of the predatory flatworms infesting the Bryopsis are very fast and eat veligers like candy. Little by little, we are figuring things out.
How to make a baby slug
As we start to figure out how to propagate these guys, I thought I’d share a little of the life cycle.
First, when two slugs love each other very much, they become very close. Because they are hermaphrodites, anyone they meet is a possible partner. Since fattening up on Bryopsis, they have been in the mood for love rather frequently. Yes, there really are two slugs in this photo.
Slugs mating 10/30/14
The next morning, there was a nice egg mass. In fact, there were two, one on each side of the plant.
Egg mass collected 10/31/14
Since I knew within about 12 hours when the mass was laid, it seemed like a good idea to collect it and get a better sense of how long the eggs take to develop on the bookshelf. Time permitting, I have been taking photos of the embryos during their development, and they should appear shortly.
Floaty Slug
I have no idea if this is a natural behavior, but it happens quite regularly in the Box of Slugs. This slug is perfectly healthy, she just seems to have decided to drift in the water column for a little while before going back to feeding.
It probably explains why they never seem to survive very long in reef aquaria, which have strong currents and plenty of pumps to suck in a floating slug and chop it to bits.
The rest of the Family
There is a total of five ponies in the tank, and I introduced two of them a few days ago. The other three were feeling neglected, so here they are.
From a distance, this male does not look all that interesting, A closer look shows just how handsome he is.
Male 2 among Halimeda 10/22/14
This female is not as colorful as the others, but is larger and more robust than her girlfriends.
Female 2 10/22/14
Last, but absolutely not least, is this little green beauty. She is still small and skinny, but is an amazing yellow-green that does not show up very well in this photo. Like the rest of the cohort, she spends a lot of time hanging quietly in awkward positions, with occasional sprints to new locations.
Female 3 hunting 10/22/14
Yes, this is a blog about slugs. Not much news at the moment about them, though. One of the students is helping me work out protocols for raising some babies for anatomical studies. Mostly, though, they sit on the Bryopsis like a herd of legless aquatic cows. They have taken on a wonderful deep green color.
Herd of grazing slugs 10/22/14
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