Echinodermata! Starfish! Sea Urchins! Sea Cucumbers! Stone Lillies! Feather Stars! Blastozoans! Sea Daisies! Marine invertebrates found throughout the world's oceans with a rich and ancient fossil legacy. Their biology and evolution includes a wide range of crazy and wonderful things. Let me share those things with YOU!
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Wednesday, September 23, 2009
2009 Pacific NW Expedition: "My God Its full of Stars!" (plus rocks)
So, if there's ONE thing I can say about this cruise?
I saw a LOT of deep-sea animals!
DEEP-SEA echinoderms!
ESPECIALLY starfish!
In fact, I'd say that its safe to say I've seen MORE deep-sea echinoderms (especially starfish) ALIVE on THIS single expedition then I've EVER seen on any single prior trip.
I've been on over a dozen deep-sea cruises, with both trawl nets and submersibles. Cruises that use trawl nets are great for collecting more specimens but are poor on observations of the animal in its natural state.
Subs, especially those which are manned, are GREAT for watching animals in their natural habitat and collecting animals in perfect condition but you ultimately don't get nearly as many specimens to study.
Remotely Operated Vehicles (ROVs), are in many ways more efficient than manned submersibles. Everyone can participate, you don't have a fraction of the science team up on the ship waiting for the others to come back and you have lots of room for storage. Plus, many of the newer ROVs can go much deeper then some of the older vehicles. (The Doc Ricketts can go down to ~4000 m or so)
What sorts of unique data can you collect exploring with submersibles that you can' t get with a trawl net??
1. Ecological Interactions. We got to see this at least twice (to my memory) but here we have an OUTSTANDING photo from the northern Cleft segment of the Juan deFuca Ridge (at about 3000ish? meters) showing predation in the deep-sea!! The big orange guy is the rare goniasterid Evoplosoma feeding on a Bamboo coral. You can hear the bamboo coral being eaten alive! Muahhahaha!
Evoplosoma is REALLY rare. There are less then a dozen specimens of this animal known. Now, not only do we know more about where it lives but we know what it eats.
You wouldn't be able to really see this from trawl specimens, much less get the specimen in perfect condition. Museum specimens of this animal are pretty badly trashed by trawl nets when they are collected.
2. Appearance of the Animal in its Natural State.
Up next...the strange "Slime Star" Hymenaster! These pix show it alive but really don't give you the full monty of just HOW frakkin WEIRD they are..
From the side view..you can sort of pick out the thickness and the little bumps that come off the top. Plus, as a bonus, we got to see it eating!
The entire body of this animal appears to be made out of a solid gelatinous material.
Hymenaster is like a jellyfish had sex with a sea star resulting in THIS thing:
and yes, its HUGE! Almost a FOOT across!!!
Close up? It looks like this. See those white rods? Those are some of the endoskeleton INSIDE this thing's solid-gelatin-like body.
In a closeup shot here..you can literally see THROUGH the body into the skeleton!!
You can barely tell, but there's an opening here called the osculum. Where the mucus comes out!!A strange and alien land under the sea...
Of the starfish..we saw several GIANTS!!
This brisingid (click here for background on brisingid biology) starfish was observed on President Jackson Seamount and was nearly TWO FEET across!! Some are thought to get to be almost TWICE this diameter!!
Not everything we saw was as big..but some were plentiful and eye-catching! This was also on President Jackson Seamount!! A pantheon of brisingids sitting on a sponge!!!
Brisingid starfish are suspension feeders-and so sitting on rocks, sponges, and other raised perches gets them into the current they need to feed !
Other big things?
This giant astropectinid (probably Thrissacanthias) from Pioneer Seamount! This beast was good sized as you can see!! (Gillian used for scale!)
Some of what we saw was familiar....Poraniopsis from the California/Washington/Oregon coast... Species to be determined!!
And what about NEW SPECIES??? Did we get many of those???
Honestly, there was a HUGE number of new taxa discovered! But for various professional reasons I can't post too many pictures of those animals here.
But here's one to tantalize all of you....a new genus and species of deep-sea goniasterid sea star living on sediment at a hydrothermal vent field!! You can see the vent clams in the background!!
It doesn't look like much from a distance, but up close- its a beautiful, sexy beast!So, what else did we see?? Lots of stuff!
CRINOIDS! (unstalkd and STALKED)!
oh yes..and we saw a FEW brittle stars. But only JUST a few HUNDREDS OF thousands...
We saw SEA urchins!! This particular one is an Echinothuriid which you can read about here!
Those of us on the cruise discovered that deep-sea echinothurid urchins can STING just like their tropical shallow-water counterparts!! So, be careful out there!
...and of course, we saw friable volcanic rocks! of MANY different varieties!! Deep-Sea lava! Glass! Yow!
We also took time to do some deep-sea pressure experiments!! Styrofoam cups to 2000-3000 meter depths change dramatically when all of the gas and porous space is crushed out of them!!!
But ya' know what's one thing you never run out of when you're out in the middle of the North Pacific?? Sunsets!!!! ( there's actually a sunrise in here as well!-can you tell which one??)
...and of course you have a bunch of PhDs out on deck taking pix of those sunsets for their scientific talks!!
....For many of the other science team members, the return to land meant the end of the expedition. But for many of us..the data collection and the specimen analysis will be used for analysis and study for YEARS.
Almost NOTHING (from a biodiversity POV) from this area had been known previously.
and now?
Much of the preliminary on-ship study suggested that a LOT of the animals collected were new.
New species and in some cases, new genera.
New behavioral observations.
New records.
The cruise is over but the discovery (and the excitement) is just beginning!
I think that Hymenaster is the coolest and most bizarre undersea creature I have ever seen. Quite cool!
ReplyDeleteI also loved learning about the hymenaster. Now I'm trying to get the image of a jellyfish and starfish having sex out of my brain. Anyway, glad you had a good trip and glad you are home again.
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