Purple Sea Urchins

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ystrout

Contributor
Messages
151
Reaction score
85
Location
San Diego
# of dives
25 - 49
Hi Everyone,

I've gone on a couple dives recently where every nook and cranny seemed to be infested with purple sea urchins. There were absolutely tons of them, like 50-100 in 100 square feet. There was still kelp and it was healthy but I wondered how long that would last.

So I had a few questions.

1. What benefits do purple sea urchins provide to the eco-system? I know the harm they cause, but what are they good for? Also, this is in SoCal where there are no sea otters that munch on them. I know other things eat them like sheephead, but I can't think of their population being that out of control ever being a good thing.
2. Is there any commercial value for purple urchins? I would think so, but if their population is that out of control, I would think they're not fished for a reason
3. If there is value for them, is there reasonible demand for their uni? Would it be easy to fish them and line up a buyer?

What I was thinking is that it would be fun to dive for urchins on the weekend (I work a job full time so this would just be a fun way for me to mess around while making some extra cash). I feel that my partner and I could easily load hundreds, maybe a thousand, into my boat on a two tank dive. Then sell them and make some good cash.

I would do this until I get bored of it then just go back to sight seeing diving. Well, I'd make sure I pay off the commercial fishing license first haha.

Thanks
 
We have some form of purple urchins here in Nova Scotia, and what are called "urchin divers". I THINK they collect them to sell or eat themselves. They come in various colours, more likely green (and multi-colored), and have short dull spines that you could pick up carefully with bare hands. They are usually found in big bunches, only in certain areas. I have a few as decorations. They're a pain to clean out.
 
2) not really. they are too small for uni for the most part. the uni you see at sushi places comes mostly from red urchins. also with the current thin kelp cover, they are pretty shriveled up and empty inside.

CDFW upped the take limit recently to 20 gallons, and the norcal underwater hunters are sponsoring an urchin removal over memorial day weekend at ocean cove
 
You have to get a commercial urchin harvesting permit from DFW.
Good luck with that, there are only so many issued and ladt time I checked all permits are spoken for. You could buy out somebody elses permit by buying their boat with a permit. You could also apply for and pay the fee for a deck hand license and work as a walk on diver. You actually may have to do this first before being eligable to buy a full blown permit.
I used to know all the rules but it’s been a long time. Best bet if you want to get into commercial urchin diving is start with reading up about it at the DFW website and call them.
Also, the big fat red or black urchins are the ones they harvest. You slso can’t just sell urchins on the street or at the back door of sushi joints. You have to sell the product to a licenced buyer and they set the price. If you want to sell to the general public then you need a different permit and those are more money and hard to get. There is a seafood mafia (powerful lobby) that seems to control a lot of how permits work, who gets them, and how DFW goes about it.
Right now not much urchin comes out of US, most is Russian. Better quality right now and cheaper. Those little purple bastards are useless for eating, nothing in them hardly.
The normal predator for those little purple urchins are the giant stars which appear to have all died off for some reason.
 
When I was stationed in Italy we used to dive for sea urchins. The female was the only one that was of value due to having eggs inside. You can tell the difference between male and female by the shade of purple - the female was the "duller" of the two. They were considered a delicacy and you would eat the eggs by spreading them on top of a piece of bread.

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Always wore thick leather work gloves when collecting them.
 
Purple urchins are not the realrproblem here. Humans are. We've overfished their predators such as sheephead and also provided alternate food sources (sewage) in the past which has allowed their numbers to become problematic. Out on Catalina there are more sheephead and purple urchins tend not to be a problem since they are controlled naturally and generally are found tightly tucked in hiding places during the day. Humans are the problem in this case. If predator populations were allowed to return to natural levels, most purple urchins would definitely line. In areas of SoCal where sheephead are less abundant (such as the colder waters of San Miguel Island) you'd see urchin barrens.
 
Thanks, drbill. Urchins are fascinating creatures.

And tasty. Too bad the purple urchins aren't as ideal for eating as red urchins (as @runsongas pointed out).

When I was stationed in Italy we used to dive for sea urchins. The female was the only one that was of value due to having eggs inside. You can tell the difference between male and female by the shade of purple - the female was the "duller" of the two. They were considered a delicacy and you would eat the eggs by spreading them on top of a piece of bread.

As I understand it, what looks like eggs/roe is the gonad or reproductive organ itself.
 
Purple urchins are not the realrproblem here. Humans are. We've overfished their predators such as sheephead and also provided alternate food sources (sewage) in the past which has allowed their numbers to become problematic. Out on Catalina there are more sheephead and purple urchins tend not to be a problem since they are controlled naturally and generally are found tightly tucked in hiding places during the day. Humans are the problem in this case. If predator populations were allowed to return to natural levels, most purple urchins would definitely line. In areas of SoCal where sheephead are less abundant (such as the colder waters of San Miguel Island) you'd see urchin barrens.
We don’t have sheephead in Norcal north of the GG, so that was never the predator here. A long time ago it was the large northern otter that used to feed on urchins and abalone. The Russians took care of those many years ago. Transplanting the smaller central and southern California otters has been unsuccessful because the conditions are too harsh for them to survive.
When I started diving here there were not many little purple urchins. We had a pretty good amount of big reds around though. There was also an active urchin fishery at that time so the reds were held in check to some degree.
The main reason for the current problem is pollution, very simple. Determining the source of pollution is another deal. They like to blame everything except the big culprit which is grape farming/big wine industry and fertilizers, waste products, etc. The politicians and policy makers will not bite the hand that feeds them. So they blame house cat feces, street runoff, dairy cows, Japan, China, etc.

The urchin problem is normally controlled by voracious giant stars up here. I’ve seen time lapse video of giant stars chasing and outrunning urchins that were frantically and unsuccessfully trying to get away.
Other stars also feed on them.
Years ago I used to see rocks that were all pocked with hundreds of little ice cream scooper shaped divots in them caused by urchins and not one urchin to be found sround the area. This old evidence of historical urchin barrens tells me that this is not the first time we’ve had urchin infestations.
 
Purple urchins are not the realrproblem here. Humans are. We've overfished their predators such as sheephead and also provided alternate food sources (sewage) in the past which has allowed their numbers to become problematic. Out on Catalina there are more sheephead and purple urchins tend not to be a problem since they are controlled naturally and generally are found tightly tucked in hiding places during the day. Humans are the problem in this case. If predator populations were allowed to return to natural levels, most purple urchins would definitely line. In areas of SoCal where sheephead are less abundant (such as the colder waters of San Miguel Island) you'd see urchin barrens.

Bill, did you guys get the sea star wasting disease down there? I know that when it hit up here the whole area started filling up with urchins. I never realized how much they were kept in check until that disease pretty much wiped out the sea star population ... which is fortunately beginning to make a comeback ...

... Bob (Grateful Diver)
 
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