NorCal Kayak Anglers

Dive Zone => Kayak Diving and Spearfishing => Topic started by: dirkbeachman on October 24, 2017, 09:56:29 AM

Title: answer to urchin plague?
Post by: dirkbeachman on October 24, 2017, 09:56:29 AM
Matt Mattison shared this link with me and I thought many of us who dive or fish north of Golden Gate bridge would appreciate it:

https://www.youtube.com/watch?v=AaXExXw4R0A

Now I know what to ask Santa for! 

Matt is working on a project to do a number of 50' x 1000' wide urchin-free strips, be very interesting to see how they hold kelp and fish or whether the urchins invade and repopulate the area.
Title: Re: answer to urchin plague?
Post by: LilRiverMan on October 24, 2017, 10:37:49 AM
Answer = transfer more Sea Otters to north of the Gate. A Sea Otter can consume 70+ Urchin a day
Title: Re: answer to urchin plague?
Post by: polepole on October 24, 2017, 10:39:22 AM
What are they going to do with the removed urchins?

-Allen
Title: Re: answer to urchin plague?
Post by: Chet on October 24, 2017, 11:42:45 AM
Answer = transfer more Sea Otters to north of the Gate. A Sea Otter can consume 70+ Urchin a day

Sea Otters will destroy abalones. Abalones are their candies.
Look at Monterey, the only abalones alive are tucked back in the smallest crevices.
Title: Re: answer to urchin plague?
Post by: hightide on October 24, 2017, 12:50:38 PM
Make the illegal to harvest.  This will give poacher incentive to harvest by the tons :smt044 :smt044
Title: Re: answer to urchin plague?
Post by: DG on October 24, 2017, 12:51:09 PM
What are they going to do with the removed urchins?

-Allen
They are giving them away for whoever wants them.  Art projects, crappy food, or fertilizer. 

Let me know if anybody wants bulk purples and I can contact John the Diver and make that happen. 
Title: Re: answer to urchin plague?
Post by: Sin Coast on October 24, 2017, 12:54:56 PM
I wonder if the practice of removing them en-mass will cause them to release eggs/milt into the water...?
Title: Re: answer to urchin plague?
Post by: LilRiverMan on October 24, 2017, 02:47:57 PM
Answer = transfer more Sea Otters to north of the Gate. A Sea Otter can consume 70+ Urchin a day

Sea Otters will destroy abalones. Abalones are their candies.
Look at Monterey, the only abalones alive are tucked back in the smallest crevices.
.

I know that they do eat Abs but it is a small percentage. I have yet to see a Sea Otter with an Abalone and I've been around Sea Otters A LOT. I have seen them eat starfish. As we say, there are no fish in Santa Cruz. Not much in Monterey either. Is that the fault of Sea Otters ?? Sea Otters don't eat fish. Urchins are the primary food source for Sea Otters and as we have discussed too many Urchins means very few Abalone. Abalone feed on kelp fluff that drifts down to them and the connection between Sea Otters and kelp forest increases are well documented. In fact, where Otters have kept urchin populations in check and therefore allowed kelp forests to recover, fish populations triple. The recovery of Sea Otters did happen in the same period that Abalone populations decreased, but so did the overharvesting by humans and the spread of Wasting disease. Various studies at Hopkins Marine Station which is a reserve and has had a large Otter populations for an extended period, show normal Abalone populations. Some studies suggest that the large size of our Abalone is in fact due to the historical presence of Sea Otters. The article was just to long and boring for me to quote here.  If you have a study that states they have a significant impact on Abalone, please present it. .
Title: Re: answer to urchin plague?
Post by: NowhereMan on October 24, 2017, 03:25:21 PM
Attach that to the marine version of a roomba and then you'll really have something....
Title: Re: answer to urchin plague?
Post by: Tote on October 24, 2017, 03:28:44 PM
I swear I could hear the abalone cheering.
Title: Re: answer to urchin plague?
Post by: BigJim on October 24, 2017, 03:47:06 PM
Answer = transfer more Sea Otters to north of the Gate. A Sea Otter can consume 70+ Urchin a day

Sea Otters will destroy abalones. Abalones are their candies.
Look at Monterey, the only abalones alive are tucked back in the smallest crevices.
.

I know that they do eat Abs but it is a small percentage. I have yet to see a Sea Otter with an Abalone and I've been around Sea Otters A LOT. I have seen them eat starfish. As we say, there are no fish in Santa Cruz. Not much in Monterey either. Is that the fault of Sea Otters ?? Sea Otters don't eat fish. Urchins are the primary food source for Sea Otters and as we have discussed too many Urchins means very few Abalone. Abalone feed on kelp fluff that drifts down to them and the connection between Sea Otters and kelp forest increases are well documented. In fact, where Otters have kept urchin populations in check and therefore allowed kelp forests to recover, fish populations triple. The recovery of Sea Otters did happen in the same period that Abalone populations decreased, but so did the overharvesting by humans and the spread of Wasting disease. Various studies at Hopkins Marine Station which is a reserve and has had a large Otter populations for an extended period, show normal Abalone populations. Some studies suggest that the large size of our Abalone is in fact due to the historical presence of Sea Otters. The article was just to long and boring for me to quote here.  If you have a study that states they have a significant impact on Abalone, please present it. .


I dunno...ton of sea otters down here in Monterey/Carmel and still way more urchins and less kelp than "usual".

I think it is more complicated of an issue than can just be solved by otters...

But I really have no clue.

 :smt001

 :smt006

Sincerely,

Jim
Title: Re: answer to urchin plague?
Post by: lucky13 on October 25, 2017, 01:22:55 AM
I wonder if it'd be better to just smash them? Wouldn't that attract fish to the area? I don't think there's any commercial value to those purple urchins. There's practically nothing inside.
Title: answer to urchin plague?
Post by: DG on October 25, 2017, 06:05:22 AM
I wonder if it'd be better to just smash them? Wouldn't that attract fish to the area? I don't think there's any commercial value to those purple urchins. There's practically nothing inside.
Commercial guys can take more.  Sport guys are limited to 35 and that won’t put a dent in any population even if they were smashed.
Title: Re: answer to urchin plague?
Post by: LilRiverMan on October 25, 2017, 09:05:18 AM
Answer = transfer more Sea Otters to north of the Gate. A Sea Otter can consume 70+ Urchin a day

Sea Otters will destroy abalones. Abalones are their candies.
Look at Monterey, the only abalones alive are tucked back in the smallest crevices.
.

I know that they do eat Abs but it is a small percentage. I have yet to see a Sea Otter with an Abalone and I've been around Sea Otters A LOT. I have seen them eat starfish. As we say, there are no fish in Santa Cruz. Not much in Monterey either. Is that the fault of Sea Otters ?? Sea Otters don't eat fish. Urchins are the primary food source for Sea Otters and as we have discussed too many Urchins means very few Abalone. Abalone feed on kelp fluff that drifts down to them and the connection between Sea Otters and kelp forest increases are well documented. In fact, where Otters have kept urchin populations in check and therefore allowed kelp forests to recover, fish populations triple. The recovery of Sea Otters did happen in the same period that Abalone populations decreased, but so did the overharvesting by humans and the spread of Wasting disease. Various studies at Hopkins Marine Station which is a reserve and has had a large Otter populations for an extended period, show normal Abalone populations. Some studies suggest that the large size of our Abalone is in fact due to the historical presence of Sea Otters. The article was just to long and boring for me to quote here.  If you have a study that states they have a significant impact on Abalone, please present it. .


I dunno...ton of sea otters down here in Monterey/Carmel and still way more urchins and less kelp than "usual".

I think it is more complicated of an issue than can just be solved by otters...

But I really have no clue.

 :smt001

 :smt006

Sincerely,

Jim

 Yep - none of these issues have simple solutions. We had problems like these back with the El Nino of 1982-83.  Global weather phenomenom trump Otters every time. However the presence of Otters will speed up the recovery of kelp, which means more fish for you Spearos. Let's face it Monterey, etc, is dive central and sadly there is a lot illegal harvesting going on
Back when I was assisting with Otter census we had Abalone pegged at about 8% of Otter diet. More recent studies put it at 5%. Not all Otters regularly eat Abalone. Certain Otters tend to specialize. It depends on what their mothers teach them to hunt for. How hard a food source is to procure also makes a difference. Abalone is about the hardest catch for an Otter to obtain.  If another food source like Urchins is abundant and easily gathered, then Otters will go for those first.  Looking into this, the negative accounts, I saw, of Otter predation, were annotated accounts from the 1950's and early 1960's. I don't exactly trust those.
Title: Re: answer to urchin plague?
Post by: bmb on October 25, 2017, 11:23:22 AM
If we've learned anything, its that quickly introducing predators to areas that they are currently are not is always a good thing, and there are never any negative repercussions to those actions.
Title: Re: answer to urchin plague?
Post by: dirkbeachman on October 31, 2017, 02:22:35 PM
LilRiverMan, I have to respectfully disagree about bringing otters back. I know there are abalone in Monterey and I've dove at Hopkins. But you definitely don't see the fat ass 7", 8", 9" abs practically everywhere like up north used to be. In fact, I don't think I've seen a legal ab in Monterey. So even if they are only 5% to 8% of a current otter's diet, that's probably because the smalls tucked way back aren't plentiful and are hard for otters to get. Why wouldn't they gorge first on giant, meaty abs if re-introduced up north.
The other big factor is that although up north was obviously part of otter's original territory, we divers have been super lucky not to be competing with them for a long time and if they got re-introduced, our voices, if the experiment ended up hammering the legal size abalone population, wouldn't necessarily prevail in a decision about removing otters. They are just about the cutest critter out there, and can't you imagine other segments of the public strongly opposing any otter removal or cull proposed by divers? I think we'd lose that debate for sure!