Standard Caribbean sea urchin - protected?

[RTRski]

Hi all. Possibly out-of-place question here, but I imagine for each locale the rules are different.

I tend to try my damndest to be a zero impact diver and never touch anything but sand when diving (and not even that if I can help it), but I happened to recently remember when diving some time ago (early 1990s, before I gave it up for a while to return last year) in the Caribbean, a guide used a dive knife to chop the spines down on an urchin and crack it open so that he could 'feed the fish' for a photo op for others in the group. The fish went berserk - I assume the urchin evolved spines for a reason, even if I can't stand "umi" sushi the other sea life seemed to love it.

At the time I remember giving him a look, and on the surface he said that the urchins were ubiquitous garbage collectors, highly populous, unprotected, and even 'damaged reefs' by eating the coral, so what he'd done was far less invasive than even allowed spearfishing and not to be considered poaching, eco-unfriendly, or anything. It all sounded good at the time, but since then, knowing just touching a finger to coral can kill that spot, I've wondered.

What are any of your thoughts on this? Is this an acceptable practice (in extreme moderation, of course) or not at all and the guy should be beaten with a sharp paddle of dead coral? This coming July will be my first time diving with a camera of my own and while I wasn't planning on even taking a knife, much less engaging in such practices to 'stage' pictures, I'm wondering if I should say something ahead of time to tell whoever our guides are I'd rather they not do anything like that on my behalf - or just keep my mouth shut....

 

[CJ's]

Urchins in the Caribbean took a bit hit a few years ago when some virus wiped out vast numbers of them. They are now actually pretty rare and also a vital part of the ecosystem so any practise like this should be frowned upon.

As we all become more aware of the fragility of our environment I would like to think that such behaviour is becoming a thing of the past but of course back in the old days urchins were abundant and apart from modifying fish behaviour this practice probably didn't have too much effect on the ecosystem. Now we just need to modify diver behaviour to prevent more harm to the reefs!!

Present thought is that any kind of fish feeding should be discouraged and I would tend to agree with that.

CJ

 

[Aqua Buoy]

The urchins that CJ's referring to are probably the black long spined urchins (Diadema sp.). They have still not recovered in most places and transplantation experiments have not helped.

Smaller, short-white spined urchins are also collected for food and most urchin fisheries in the Eastern Caribbean are permanently shut due to their low numbers, caused by over-exploitation.

So from a conservation point of view it is a practice to be avoided. I would not advise cutting up sea urchins to feed fish, I really don't see the point. If one wants a photo of a nice fish then patience is the key, if one wants to photograph fish behaviour then feeding a fish would not be naturally observed behaviour.

If fish feeding is absolutely necessary, then take some (non-frozen) fish bits with you. Again be aware of the risk of attracting other predators that may be in the water!

 

[barefootek]

I know this is an old post, but if you see the guy again beat him with the boat paddle. Urchin and Diadema antilarrum in particular feed primarily on macroalgae. Since macroalgae (seaweed)competes for space with coral, that means that sea urchin are beneficial to a coral reef. As for the populations, they are by no means endangered, but there numbers in the Caribbean are still recovering from being devastated by disease 20 years ago. Though it is only one of many factors it is not a coincidence that reefs at that time were much healthier.