OK to cut up black sea urchins?

[drbill]

By the way, I am also greatly concerned with environmental issues. But I'm also a realist, and know that there's no way the few of us divers could ever put a dent into the sea urchin population.

Not globally or maybe even regionally, but certainly locally.

 

[Kayak Diver]

Not globally or maybe even regionally, but certainly locally.

Dr. Bill...I'm missing something here, so please help me out...why are the urchins so important to the ecosystem? I've been told that horn sharks eat them, but...is that true? What else eats them? How do they fit in? Do they do anything for the ecosystem other than mowing down kelp forests? As far as I can tell, their only real purpose in life is to poke holes in dry suit seals.

 

[Kim]

Dr. Bill...I'm missing something here, so please help me out...why are the urchins so important to the ecosystem? I've been told that horn sharks eat them, but...is that true? What else eats them? How do they fit in? Do they do anything for the ecosystem other than mowing down kelp forests? As far as I can tell, their only real purpose in life is to poke holes in dry suit seals.

I saw a documentary a few days ago about this. Apparently the otters eat them.......and they eat an awful lot every day!

 

[headhunter]

I saw a documentary a few days ago about this. Apparently the otters eat them.......and they eat an awful lot every day!

Kim,

That is what actually started all of this here in SoCal.

We got rid of the otters, so we wound up with too many sea urchins and they devastated our kelp forests. It's a study in all the wrong ways to manage an ecosystem. Our kelp forests still haven't recovered from that.

Christian

 

[Kayak Diver]

Kim,

That is what actually started all of this here in SoCal.

We got rid of the otters, so we wound up with too many sea urchins and they devastated our kelp forests. It's a study in all the wrong ways to manage an ecosystem. Our kelp forests still haven't recovered from that.

Christian

Oh...I thought the otters only lived up north, where the water was nice and cold. Guess I shouldn't assume too much. Have there been any efforts by the bio's to bring them back?

 

[headhunter]

Oh...I thought the otters only lived up north, where the water was nice and cold. Guess I shouldn't assume too much. Have there been any efforts by the bio's to bring them back?

I don't think the fishing industry wants them back. I think they were considered pests.

I used to sit and watch them play and eat. They used to crack the sea urchins on their bellies while lying on their backs. They were the guardians of our kelp forests. We used to have some really thick kelp forests back then.

I don't think that anything is being done to bring them back.

Christian

 

[drbill]

A number of factors involved here. The "local" extinction of sea otters along most of the California coast (*except near Big Sur) eliminated one control on sea urchins (and abalone which also increased). Over-fishing of sheephead removed another. Sewage laden inputs from increased growth following WWII offered an alternate food source for the urchins along the mainland coast. Once the urchins had devastated the kelp beds (and their normal food supply), they were able to remain in the barrens due to reduced predators and an alternate food source (organic matter in sewage).

In short, we really screwed things up.

Otter were extending southward, but the fishing industry was vocal about not wanting them to spread into the Channel Islands and SoCal Bight. Relocations to San Nicolas Island were largely unsuccessful as the otters returned to the mainland. On occasion I have seen one here on Catalina, but VERY rarely.

 

[drbill]

We used to have some really thick kelp forests back then.

Another factor was the long-term ocean warming trend in our region that began in 1976-77 or so. It really wiped out kelp forests in the region from Long Point to the East End on Catalina. This is the region of warmest water temps around the island, so even the slight increases had a great effect here.

I remember the kelp forests at Torqua Springs near White's Landing being very luxuriant in the late 60's and early 70's. In fact they were so luxuriant I often had to anchor my boat to the kelp itself outside the main canopy and swim in under the dense kelp growth at holdfast level. In some years after the warming event, these beds were completely gone.

 

[wetrat]

I remember the kelp forests at Torqua Springs near White's Landing being very luxuriant in the late 60's and early 70's. In fact they were so luxuriant I often had to anchor my boat to the kelp itself outside the main canopy and swim in under the dense kelp growth at holdfast level. In some years after the warming event, these beds were completely gone.

This is fascinating learning about local marine ecology from people who have lived through these kinds of changes. I've lived in So Cal for 18 years and never knew we used to have sea otters and even more expansive kelp forests here. Now that I know more, I feel compelled to educate people about how fragile our local ecosystem is. I guess you could say I've gone from Sea Urchin serial killer to environmental activist!

Thank you for the great contributions to this thread DrBill, Headhunter, Kim and Kayak Diver! :god:

wetrat

 

[JDog]

I think I liked Shakas' old avitars better. OK back to the urchins.