Join me in the cold, dark, life-sustaining NE Pacific Ocean to discover the great beauty, mystery and fragility hidden there.

Posts tagged ‘limpet’

Beware of taxi-crabs and “Cling like hell to your rock”

Oh how did I get to be today-years-old without knowing of this Robert Service poem that is so timely and speaks for a limpet?

His poem “Security” includes:

So if of the limpet breed ye be,
Beware life’s brutal shock;
Don’t take the chance of the changing sea,
But – cling like hell to your rock.

Yes!

Full poem is below which includes life lessons about taxi-crabs 🦀

Keyhole Limpet which I photographed near Port Hardy. Diodora aspera builds a shell up to 7.6 cm across.


 

Security
Robert Service

There once was a limpet puffed with pride
Who said to the ribald sea:
“It isn’t I who cling to the rock,
It’s the rock that clings to me;
It’s the silly old rock who hugs me tight,
Because he loves me so;
And though I struggle with all my might,
He will not let me go.”

Then said the sea, who hates the rock
That defies him night and day:
“You want to be free – well, leave it to me,
I’ll help you get away.
I know such a beautiful silver beach,
Where blissfully you may bide;
Shove off to-night when the moon is bright,
And I’ll swig you thee on my tide.”

“I’d like to go,” said the limpet low,
“But what’s a silver beach?”
“It’s sand,” said the sea, “bright baby rock,
And you shall be lord of each.”
“Righto!” said the limpet; “Life allures,
And a rover I would be.”
So greatly bold she slacked her hold
And launched on the laughing sea.

But when she got to the gelid deep
Where the waters swish and swing,
She began to know with a sense of woe
That a limpet’s lot is to cling.
but she couldn’t cling to a jelly fish,
Or clutch at a wastrel weed,
So she raised a cry as the waves went by,
but the waves refused to heed.

Then when she came to the glaucous deep
Where the congers coil and leer,
The flesh in her shell began to creep,
And she shrank in utter fear.
It was good to reach that silver beach,
That gleamed in the morning light,
Where a shining band of the silver sand
Looked up with with a welcome bright.

Looked up with a smile that was full of guile,
Called up through the crystal blue:
“Each one of us is a baby rock,
And we want to cling to you.”
Then the heart of the limpet leaped with joy,
For she hated the waters wide;
So down she sank to the sandy bank
That clung to her under-side.

That clung so close she couldn’t breath,
So fierce she fought to be free;
But the silver sand couldn’t understand,
While above her laughed the sea.
Then to each wave that wimpled past
She cried in her woe and pain:
“Oh take me back, let me rivet fast
To my steadfast rock again.”

She cried till she roused a taxi-crab
Who gladly gave her a ride;
But I grieve to say in his crabby way
He insisted she sit inside. . . .
So if of the limpet breed ye be,
Beware life’s brutal shock;
Don’t take the chance of the changing sea,
But – cling like hell to your rock.

 


I ensured this is indeed Robert Service in all his glory by ensuring it was in the “The Complete Works of Robert Service” (1945) but could not find further detail on when he wrote it.


My additional posts featuring limpets:

 

Who You Calling “Unstable”?

Don’t you hate when people use a provocative “hook” to get you to read their material? Yes, that’s what I’ve done but I promise you, it is worth it.

While I think all of us are a little unstable right now, this blog is not about me. It’s about the astounding adaptations of a little limpet assigned the name of “Unstable Limpet” (Lottia instabilis). 

Unstable? This species just limpetted along on its own evolutionary path!

Most other limpet species are shaped so they can suck down securely on a FLAT surface for protection This works well because these most often graze on algae encrusted rocks. But the Unstable Limpet can secure to a ROUNDED surface.

Which rounded surface? Oh I will never forget the first time I noticed this species and realized the marvel of the adaptation. Unstable Limpets are shaped to be able to hunker down on the cylindrical stipes (stem-like structures) and holdfasts of the kelp species upon which they also feed!

Screen grab from “Invertebrates of the Salish Sea”. Caption: “The uneven edges of the shell of Lottia instabilis can easily be seen in this end and side view. The shell is shaped to fit snugly around a round stipe instead of a flat surface.”

I suspect that, like their flat-shelled brethren, Unstable Limpets have a specific spot to which they “home” and where their shell fits perfectly.

As is supported by others’ observations, I have found Unstable Limpets living / feeding on Old Growth Kelp (Pterygophora californica) and Split Kelp (Laminaria species).

Underside of an Unstable Limpet on the stipe of kelp.
An individual with a lot of coralline algae growing on its shell.

I hope that this little limpet leads to you reflect anew on the wonder of the natural world around us and . . . about how being “unstable” just might mean being better adapted to the conditions you are in. It may even be of benefit in having a unique place and perspective in the world. 🙂

Below are further details about the species and an explosion of my photos documenting them.

Unstable Limpets and a Brooding Anemone on the stipe of Old Growth Kelp.

Size: To 3.5 cm across

Known range: Northern Alaska (Kodiak) to Southern California (San Diego) from the intertidal to 73 metres depth.

Variation: Greg Jensen reports that: “Some members of this species settle on rocks, where they develop a more conventional limpet sharp and are difficult to distinguish from other limpets. This rock form was previously known as Lottia ochracea.” (Source: Jensen)

Behaviour: If touched by predatory sea star species, the Unstable Limpet “vigorously” runs away. Predatory sea star species referenced in the study are Six-Rayed Stars( Leptasterias hexactis), Sunflower Stars (Pycnopodia helianthoides), and Ochre Stars (Pisaster ochraceus ). It was unclear to me from reading a summary of the research (and being unable to find the original paper) if this response behaviour is different if the Unstable Limpet is on its “feeding scar” (a bit of an indentation in the surface of the kelp). It may be that it responds then like the Seaweed Limpet (Discurria insessa) whichusually responds to contact by elevating its shell (“mushrooming”) and rocking from side-to-side, but rarely moving away from the scar.” (Source: Snail’s Odyssey).


Little limpet. Long stipe of kelp.
This individual may have had another limpet species feeding on the algae on its shell.
I believe you can see the scars here of where the limpet has been feeding on the kelp.

The following photos offer additional perspectives on two of the individuals shown in photos above.

I believe you can see where this individual has been feeding and yes, thats a lovely hat of algae that is growing on the shell.

Sources:

  • Jensen, Gregory C, Daniel W. Gotshall, and Miller R. E. Flores. Beneath Pacific Tides: Subtidal Invertebrates of the West Coast. , 2018. Print.
  • Lamb, Andrew, Sheila C. Byers, Bernard P. Hanby, Bernard P. Hanby, and Michael W. Hawkes. Marine Life of the Pacific Northwest: A Photographic Encyclopedia of Invertebrates, Seaweeds and Selected Fishes. Madeira Park, BC: Harbour Publ, 2009. Print.
  • Homna, L. 1995. DISTRIBUTION, ABUNDANCE, AND REPRODUCTION OF THE ALGAL SPECIFIC LIMPET, LOTTIA INSTABILISMaster’s Thesis. Moss Landing Marine Laboratories, San Francisco State University. 77pp.
  • Snail’s Odyssey; Limpets & relatives – Predators & Defenses: Escape-crawling from Seastars
  • Walla Walla University. Invetebrates of the Salish Sea – Lottia instabillis