Posted by Eric Frasco on August 06, 2002 at 23:08:00:
For those of us that have been diving for many years, it has been painfully obvious that there have been many significant changes in the Marine Ecosystem, especially in recent years.
Those of us that have been diving 10+ years in the local environment, we all have stories about depletion of species and the impact it has had on the quality of diving. But that is not what this post is about. This post is not about MPAs and whether or not they are needed or where they should be (put me on record as supporting them, but also put me on record as being concerned about their placement and their management, and as being very concerned about the criteria that will be used to evaluate their effectiveness).
No, this post is about nature being out of balance. Biodiversity (Biological Diversity, or the diversity of marine species) is not an issue that is discussed very often on this web page. Instead, nearly every posting related to conservation issues seems to be single minded or extremely polarized towards either the left or right. It seems that the folks that are posting want to reduce the issues to either "for" or "against" - an apparent effort to reduce the issues into a simple one-dimensional "black and white" contrast.
Unfortunately, it "JUST AIN'T THAT SIMPLE, FOLKS."
From Hillary Vider's "Marine Conservation for the 21st Century" (c1995 by Best Publishing Company, ISBN paperback #0-941332-46-2), Biodiversity is often divided into three distinct categories:
1. Genetic biodiversity (diversity within a species);
2. Species biodiversity (diversity among species; and
3. Ecosystem biodiversity (diversity among ecosystems)
Over the last few years, I have started to notice that there are more and more dive sites that seem to be dominated by only one or a few single species of marine life. At sites on Catalina and on the backside of Anacapa, and at several other locations throughout the Channel Islands, I have seen many areas that were dominated by brittle stars. There were still a few other types of life there, some larger starfish, and maybe a few wrasse and perhaps some blacksmith, but there was a distinct absence of kelp, snails, rockfish, and other fish. These sites were primarily acres and acres of brittle stars.
In my opinion, to see such large areas dominated by a single form of marine life is a failure of species biodiversity. I cannot believe it is healthy for such large areas to be dominated by a single species. We have had similar examples with sea urchins, and we even gave a name to areas that were dominated by urchins: "urchin barrens."
With that said, I want to examine the issue of black sea bass. In just the last few years, much to the pleasure of many divers, there have been many shallow locations that are now sporting significant numbers of black sea bass. I have to agree, they are beautiful creatures, wonderful to watch and photograph, and since they are not the least bit scared of humans you can get really close to them. In all, a wonderful experience.
But they are carnivorous creatures. Do you know how they get so large? Let me give you a hint. Kelp is not a primary constituent of their diet. They eat other fish or other marine life. And they have to eat a lot of that to get as large as they are.
More and more, we are hearing reports of black sea bass. And they are being reported with increasing frequency at more and more locations. On the upside, it is great to see that protection of a species has resulted in an apparent recovery of the population of that species (although it took a good twenty years to do so). On the downside, this huge population boom means that a very large predator at the top of the food chain is beginning to become so populous that it could possibly dominate extensive areas of our marine environment.
So, what position will we be in if it turns out that this black sea bass population boom starts to affect the other fish populations? These black sea bass are going to eat something. What are we going to do if it turns out that the black sea bass are eating so many kelp bass or squid or octopus that their successful recovery poses a threat for other species?
What if it comes down to an issue of Big Fish (black sea bass) versus Little Fish (everything else that the black sea bass eat)? What if it comes down to an issue of an imbalance in the overall biodiversity of our marine environment?
One point that I'm trying to make here is that we cannot manage nature on a species by species basis. We have to look at the entire ecosystem and base our management principles on the whole ecosystem. We have to be ready to adjust our management criteria for the whole ecosystem, not just one species that happens to be our favorite marine animal. If the black sea bass population booms and threatens the stability of the, say, kelp bass population, are the zealots that are preaching "save the black sea bass" going to change their tune and start singing "save the kelp bass?"
I think not.
It is easy to try to immaturely paint this situation as having an easy solution. Many folks feel quite comfortable by reducing the situation to a stark "black and white" contrast. The situation is extremely complex, and it is tempting to reduce it to "outlaw spearfishing," or "keep divers out of kelp forests." Unfortunately, these arguments reduce the situation to an "Us versus Them" situation: Non-consumptive divers vs. Spear fishers; Recreational vs. Commercials; and on and on.
The bottom line here is that the real issue is not "Us vs. Them" but rather how all users of the resource interact together and interact with the environment, and how effectively they all work together to do the best job possible to sustain and manage the marine environment.
I sincerely hope that I see some more mature postings in the future regarding these issues. Statements such as "outlaw spearfishing" carry about as much interest to me as "Gee, I hate having to get up and go to work in the morning." Maybe the folks that are making such one-dimensional postings should go visit an AOL chat room or some other web site where they can get their jollies, rather than wasting our time with such childish postings. GROW UP!
I propose that the readers of this web page REFUSE to respond to anemic, one-dimensional comments such as "outlaw spearfishing." Postings such as these are clearly the product of shallow minded idiots that wish to stir up a flame war on this web page. Postings such as these are clearly the product of self serving individuals that want nothing other than to wrestle the attention of the readers of this page away from the real issues and instead sensationalize and refocus our attention on their own petty issues.
Let us, as a community, discourage this kind of behavior by turning or backs on it and refuse to acknowledge it.
In summary, I've said a lot about changes I've seen lately, particularly the emergence of only one or two species taking a dominant role in sites that are popular to divers. Is this a trend or is this a byproduct of the decline of the marine environment? And if we want to manage it, how should we go about it?
If you are going to respond to this posting, please be specific, quote references if possible, and give examples. I would prefer that kind of a response to an emotionally charged opinion. Let's get a real discussion going, not another finger pointing, sound biting, posturing sequence of name calling posts.
I'd really like to see if the readers of this page can work together to reach some realistic goals, rather than just piss all over each other.
I look forward to your comments on marine biodiversity, and your comments about taking the moral high road in regards to having meaningful discussions about issues that affect the entire diving community.
Any response postings that are not within those guidelines, I suggest that we label them "NR (nt)" for "NOT RELEVANT (no text)" for being irrelvant or inappropriate to the topic under consideration.
Thanks for reading this long post. I sincerly hope it stimulates some meaningful dialog.
-Eric-