Zen of the Feeding Sea Cucumber

      

You know what I find relaxing? Sea cucumbers. Specifically watching sea cucumbers just moving along wherever they happen to be and slowly and methodically digesting food from off the bottom of the ocean..

There is a real.. peace from watching them. Slow. Confident. Unworried. Sea pigs and other sea cucumbers... all with their benthic detrital serenity. Its soothing really.

Today: a little gallery showing some nice closeups to ease that tired day today!

Sea cucumbers are versatile creatures. Some species can actually feed with filter feeding apparatus inside their anus  (shown below). If you're not feeding from the front there's always the other end...

Here's the business end: the mouth on some glass, picking tiny detrital food off the surface. Although "scavenger" and "detritivore" doesn't sound very glamorous, it turns out that this serves a vital function to ecosystems in both shallow and deep-sea ecosystems (see the secrets of sea cucumber poop here! )  Sediment is aerated and "turned over" and doesn't just build up anoxic organics... etc.

here is where it all starts!

                 
Some nice video of a Japanese species showing aforementioned feeding tentacles which are used to pick food off the substratum 

Several more species with their feathery feeding arms extended..

Here's a nice one showing one of the feeding arms with food being moved INTO the mouth...

and here...

and let us end with one of the most beautifully shot sea cucumber feeding videos!! Taken by "liquidguru"! 

Lembeh Magnum Sea Cucumber from liquidguru on Vimeo.

Its Sea Cucumber Spawning Time!

Image from the "FunSea" video below

Springtime! Springtime! Springtime! When fertile sea cucumbers realize that its the season to begin emitting their gametes into the water! Some sooner, some later..but it eventually becomes time!

Many echinoderms appear to adopt a particular stance when emitting gametes.  This bit I wrote awhile back shows sea stars and brittle stars standing up on their tippy toes for example. 

Theyposition themselves into the water column in order to take advantage of better water currents for their gametes to disperse. Or at least, that's what seems to be the case. This reproductive posture is actually not all that well understood.

So, its time for ANOTHER installment of sea cucumber spawning!!

One important thing to realize? That in spite of their shape and the color of the materials being emitted, we CANNOT identify the sex of the sea cucumbers in the pictures. 

This diagram nicely sums up the difference in reproductive material. One emits the male gametes while the females emit the egg. But its likely not the case that they are always this conveniently near one another..

This image borrowed from A snails' Odyssey blog here! Great info! 

The eggs and the sperm meet in the water and fertilize in the water column.  Once fertilization occurs, the fertilized egg matures into a specific sea cucumber larvae, known as an auricularia (sometimes referred to as the auricularia stage): 

And it is the above larval stage which undergoes several more stages of growth until it settles onto the sea bottoms and matures into an adult sea cucumber.

BUT to get there, the adults have to spawn! Here's a great shot of what seem to be at least 2 species of sea cucumbers from the Atlantic (Stetson Bank in the Flower Garden Banks, National Marine Sanctuary).

Since these guys are likely trying to take advantage of the same water current to carry their gametes to their destination, several individuals (from different species) are likely to find locations in the same general area. 

This one seems to have found a particularly safe area around some diadematid urchins...

From Japan, we have several very nice video captures of various sea cucumbers in spawning position...

Their postures are fairly arched and position the body well into the water column.

And here are further examples of sea cucumber species emitting gametes from around the world..

In stark contrast, some other species seem to be closer to the bottom during this period, with only part of the body raised off the ground.

Interesting that both of these are on sandy bottoms. Coincidence? Difference in species? Hard to say.
                   

IN CONTRAST, there's other deep-sea sea cucumbers, as presented in the NMNH Invertebrate Zoology blog,  which actually huddle together to optimize reproductive success (image from this new paper!)

An increasingly common sight on crowd-sourced media and on deep-sea exploration! Simple observations which remain a fertile area of study... (yes. I went there!)

Some bonus swimming sea cucumber video!!

Recently made available to the Echinoblog!  by Emily B.!  Some swimming sea cucumber (Enypniastes, I believe..) video from the Gulf of Mexico...


Here's a few more classics-all conveniently here in one place!



A different genus..Paelopatides? 



Yet another..Peniagone


Have a great week!

NEW! Sea Pig & other Deep Sea Cucumber videos!

So, because Neptune Canada has gone and posted this new deep-sea "sea pig" video.. I've been compelled to go and collect as many deep-sea cucumber vids as I can find and put them here!

Enjoy!

This one is an elasiopod sea cucumber, similar to but different from Scotoplanes below.. This was identified by Dave Pawson as either Amperima or Periamma, but is close to Amperima rosea (Perrier, 1896). From the North Pacific...

Observed here feeding on the fine, fine mud of the deep-sea bottom!

Want to know more about "sea pigs"? Click here.


And here's Paleopatides, I believe?

Deep-Sea Sea Pen (Umbellula) & Swimming Sea Cucumber Video! Also courtesy of Neptune Canada! (cuke begins at 1:00 into the video)


I believe this is Enypniastes? bioluminescence.....

Video of the sea cucumber Peniagone swimming...

Hmm.. not sure which one this is..


Enypniastes eximia...an oldie but a goodie!

Sea Cucumber FEEDING videos!! Tentacles! Nom Nom Nom! Go!

Ya' want mouth feeding tentacles? I got em' right here!

So, what we're seeing in each of these videos is the ring of feeding tentacles around the mouth of a sea cucumber. That's the "wormy" group of echinoderms that likes to sit around eating sediment and detritus all day!

You can note that in almost all of these the feeding tentacles are moving food from the substrate and "licking" the goodness off into their mouth!!

Enjoy!




Here's a cuke from Lembeh


A Japanese(?) synaptid sea cucumber


A Japanese/tropical Pacific species


One labelled "Dendrochirotida" but not sure if that is so...


not sure where this one is from..

Videos of Sea Cucumbers doin' Sexy' Swimmin' Crawly STUFF' !

I have some good stuff coming up, but this week got away from me.. So in the meantime, here's some neat sea cucumber videos that I've been meaning to share....

A giant holothurian doin some kinda sexy thing! There is some gamete emission towards the end and is kind of understated, so keep your eyes open...



Here is a nice compilation of deep-sea marine invertebrates from off Kona, HI shot by the NOAA Okeanos Explorer... Some fantastic hi-def video of the swimming sea cucumber Paelopatides from 0:28 to 0:45 into the video.. The rest of it is mostly not echinoderms, but also interesting...


And finally, if you want to see some MORE neat deep-sea sea cucumber goodness! Go HERE for footage from the Indonesian deep-sea INDEX 2010 expedition video...

A giant synaptid sea cucumber (identified as Synapta maculata) on the move!


Not sure where this video was shot, but possibly the Indo-Pacific..


...and video of another sea cucumber feeding. You can see the tentacles moving food into the mouth.. From Lembeh Straits in Indonesia.



And of course, where would we be without watching sea cucumbers POOP!?

More deep-sea cukes! Swimming Sea Cucumber Enypiastes!!

Its Thursday! Continuing our deep-sea cuke theme this week!

We live in a wonderous world. No less then THREE videos of the deep-sea swimming cucumber -the genus Enypniastes- are now available for all to see!!

1. Enypniastes BEAUTIFUL close up footage of the beast swimming! (note that the term "spanish dancer" usually refers to a species of swimming nudibranch/sea slug)


2. Bioluminescence!


3. Swimming! (narrated by Bob Carney-Louisiana State University)

When Sea Cucumbers eat plastic-somethin's WRONG!

So, I'm running late on World Oceans Day..but its been a busy day..

I've brought attention to some of the effects of global warming recently on asteroids and others have written about ophiuroids but have not written much about the effects of pollution on echinoderms...

(Thyonella gemmata from the Smithsonian Fort Pierce Field Guide Site)

Today, I bring to your attention a new paper by Erin R. Graham (Saint Joseph's University) and Joseph T. Thompson (Franklin & Marshall College) in the 2009 Journal of Experimental Marine Biology and Ecology-"Deposit-and suspension-feeding sea cucumbers (Echinodermata) ingest plastic fragments".

The effects of this:
Plus this:

(Cucumaria frondosa from Norwegian seawater.no site)

= trouble???

The authors of the study studied four subject species: Holothuria fieldana, H. grisea, Cucumaria frondosa and Thyonella gemmata in the lab and compared these results with data from three different field sites along the Atlantic coast.

(Holothuria grisea from the Smithsonian Ft. Pierce Taxonomy site)

They used these to study the experimental feeding rates/effects of small plastic bits as they were ingested by sea cucumbers, which are widely ecologically important deposit feeders.

Lab Analysis
The feeding component basically involved artificially seeding an artificial aquarium with plastic shavings and many different kinds of plastic bits-thread, rods, bits, etc.
They discovered that sea cucumbers were preferentially ingesting between 2 and 20 fold MORE plastic fragments per individual (per 4 hour interval) then was expected (I gather they assume "expected"= random).

Remarkably, one species Cucumaria frondosa ingested 73 times more plastic ribbons then expected!

They basically conclude that this was a preference of the individual species. The shapes and sizes were variable factors-but ultimately they strongly influenced the sea cucumbers' predisposition to feeding.

This becomes important in just a moment....

(Cucumaria frondosa from Norwegian seawater.no site)

Field Studies & Environmental Impacts

(from here)

The authors complemented their lab work with field studies and found 105 to 214 pieces of plastic per liter of sediment!

And MORE important? They identified the toxic PCB from one of the more northern localities at a concentration of 0.0106 ug/g suggesting that PCB can be ingested by invertebrates in these soft-sediment communities!

ADD to this? The fact sea cucumbers will PREFERNTIALLY ingest plastic bits over sediment.

What the authors didn't have full data on was the magnitude of how much PCBs would be/could be absorbed into the body tissues of individual species.

Conclusion? To spell it out:

1. Sea cucumbers preferentially PREFER to ingest plastic bits.
2. Plastic bits are COMMON in sediment (where sea cucumbers live).
3. Plastic bits can impart toxic PCBs which are ingested in great quantities by sea cucumbers.

Thus, minute plastic bits can introduce contamination into sediment communities.

So, these would be ecologically important on their own-but imagine how important this would be in places where people EAT sea cucumbers!

Because DSN Sex Week is Awesome! Echinoderm Sex Videos!!

In honor of Deep-Sea News' Sex Week theme...Its time for Echinoderm Sex Videos!!!

Please play..."shake, shake, shake" your booty to the following....

Fromia elegans emitting gametes!


Archaster engaged in Pseudocopulation!!



Sea Cucumber in provacative reproductive posture (at 0:14 into the video)


Shake, shake, shake...shake your booty! (Play this for inspiration)