Monday, April 23, 2018

The "starfish walking back to the sea" FAQ & why it is sad

So, apparently back in 2012, the original producer of this video shot this lone sea star out on a South Carolina beach as it was struggling to get back to the ocean, likely due to a mass stranding or some other event which stranded it on the tropical Atlantic beach..

Here's the original, very static heavy video: https://www.youtube.com/watch?v=tV5H1qNwFKo

and here is the "cleaned up" version which was released in October 2017...
This video went viral and was circulated widely in a huge number of widely read newspapers all over the world including The Sun, the UK's Daily Mail and oddly enough, the Indian Express

These and other venues reported it with such inaccurate hyperbole as "Incredible moment starfish WALKS down the beach after getting stranded on the sand!!" with the word "INCREDIBLE" being dropped as if this was somehow aliens landing on the Earth for the first time!


But sadly, what was happening here wasn't really THAT momentous and in fact was pretty sad.

There was no information on what was happening, what species this was or the context of this whole thing...  So here's my attempt to shed some light on this..

1. What species is this? And how does it live normally? 
This is a starfish called Luidia clathrata and these are members of a group of "sand stars" called the Luidiidae. A family with only one genus, Luidia named for a 18th century Welsh naturalist  named Edward Lhuyd whose Latin handle (they all had one!) was Luidius. One of his colleagues named this genus of sea stars after him in 1840 a story was born!

You can read lots about Luidia in a blog I wrote here in 2014!

Long story short..they eat snails, clams and other small critters in the sand. They can bury themselves in the top part of the sediment where they live.

This species in the waters of the tropical Atlantic on the US coast.. Florida, South Carolina, etc. are commonly encountered and commonly seen on beaches..

2. Seen on BEACHES? Why is THAT??
 How did this individual end up on the beach? Likely due to a mass stranding following a storm, which I've written about here... But here's a video of such an occurrence featuring many, MANY of this species stranded along the shoreline

3. What makes them so vulnerable? 
Basically these sea stars don't have a lot of "hold" on the surface because their tube feet are pointed rather than suckered. Their little tube feet are modified to help them efficiently dig into the sand or other sediment both to help them feed and to hide them from potential predators..

BUT when big waves or currents come along.. they can be swept away and taken to hostile environs such as this seashore..

Bear in mind that this species is quite abundant and while its unclear what these "natural disasters" mean for the population of these animals, I wouldn't be surprised if the recovery was relatively quick given how many of them there are..

4. What do they look like alive and "normal"???
Here is a healthy individual of this species moving naturally underwater, albeit near the beachfrot

As the video would indicate..these are actually elegant and very beautiful animals in their natural habitat. In fact, Luidia is one of the FASTEST known sea star species..


5. Why is it sad?
    So, its literally been months since the original "crawling" video posted but I STILL have this being sent to me with comments about "HOW WONDERFUL IS NATURE OCEAN" or "AMAZING OCEAN CREATURE" etc. etc... when in truth this video exploits this animal desperately trying to get back to the ocean

    There's an important consideration here: Sea stars operate using a unique series of tubes in their body called the water vascular system which operates primarily using hydraulic pressure throughout the arms and so forth. This is how they move and operate all of their tube feet and so on...
via http://www.deepseanews.com/2012/03/veins-of-water-the-evolution-of-the-echinoderm-water-vascular-system/

  The water vascular system NEEDS SEAWATER TO OPERATE.

Many echinoderms DO have a limited ability to tolerate BRIEF periods out of water..but this is essentially the animal with residual water remaining in its Water Vascular System, such as the tube feet and so on..

Fluid is still required for movement AND survival. Water carries oxygen and other necessities, such as food and etc. throughout the body. 

So, that long crawl back? is not both a crawl to return to comfort but also a return for SURVIVAL.

Folks who express the "WONDER" over that pic are perhaps extending a... misplaced emotion.. 

Fortunately the original producers of the video have said repeatedly that they had returned that specimen to the ocean shortly after they shot it. So, good on them. I thank you on behalf of the starfishes!!

So, in the meantime..can we PLEASE let the video go  and LOSE  all of the sad, misplaced hyperbole about how amazing this is?? Its just painful to watch. 

thanks. 

1 comment:

Sam Larson said...

"their tube feet aren't suckered."
I was under the impression tube feet in general weren't suckered!