The destruction of purple urchins

[chillyinCanada]

Sea urchin explosion decimates kelp forests off Pacific coast | CBC News

 

[lowviz]

You can send all the edible ones over here.

So what is it? Warming waters?

BTW, we hear not much about Humboldt squids anymore. They leave?

 

[rsingler]

Unfortunately can't eat the purple ones. Sigh.
At least they're satisfying to squash.

 

[chillyinCanada]

I thought the article said they're edible if being fed, it's when they are in shutdown mode due to lack of food source that they become icky?

 

[lexvil]

I see more loss of kelp where the coast is more exposed to the increase of and severity of storms, I see urchins and kelp together in protected coves. The water temps have also been consistently warmer and that may be a big part of the problem. I have heard that smashing them exacerbates the issue.

 

[drbill]

Unfortunately can't eat the purple ones. Sigh.
At least they're satisfying to squash.

Although I generally agree they are far less satisfying than red urchins, they are edible if fattened up in an aquaculture setting. The reason they aren't directly from the sea is that their food supply there hasn't allowed significant development of the ovaries.

It isn't the purple urchins' fault so I would take no pleasure in "squashing" them.

 

[Bob DBF]

I thought the article said they're edible if being fed, it's when they are in shutdown mode due to lack of food source that they become icky?

I don't know how destroying more kelp to fatten them up is going to preserve the kelp that they are destroying already. I guess if some company makes money off it...

On the NorCal coast over the last several decades I've seen some localized areas get decimated by the purple urchins and come back, but nothing on the scale that is happening now. I should have paid more attention, but I'm not a marine biologist so I looked at it as a nuisance rather than a phenonom to study. For a small area, acres, to return was 5 years or more, as I remember.

I have heard that smashing them exacerbates the issue.

They reproduce by broadcasting eggs and sperm, so you may help them do that by breaking them up, if developed enough. @drbill is in the thread so he would be a better source than I.



Bob

 

[Sam Miller III]

@Dr bill
I am surprised that you did not mention the Palo Verdes Underwater Restoration Program aka PURP !
Recall when divers from all over SoCal met at Whites point for PURP?

sdm

 

[rsingler]

It's pretty hard when looking at a time lapse movie of those critters destroying a kelp forest to not want to destroy the juveniles.
Yes, PURP is a great project. But I tend to look at this like lionfish. If I'm wrong about making it worse with destruction (tho' I agree about not releasing mature eggs), then I'd be happy to leave them alone.

 

[Sam Miller III]

A diver who recalls PURP !
Were you a participant in that activity ?
sdm