Ode To The Sea Urchin

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Posted by seahunt on January 04, 2000 at 12:11:56:

Ode to the Sea Urchin

Such a hard and slow creature is the Sea Urchin, but he was
the first to greet me when I was a new diver. He was what I saw
first and he is as common as leaves on a tree. And Mr. Sea Urchin
can teach you manners. Don't move carelessly or he's gonna spine
you good. He can move his spines some and with some light he
becomes a beautiful burgundy red, but mostly he's just comfortably
To the Romans, he was the source of the imperial color.
To a scientist he is Strongylocentrotus franciscanus. Such a
long name for such a slow mover. "But wait, the wonders of the Sea
Urchin are limitless." He and his cousins have a five sided radial
symmetry and use hydraulic pumps for movement. They have suckers
to hold them in place and three sided pedicellaria that can nip
an unfriendly visitor. They can grind holes in rock to make a safe
home and under their spines is a protected nursery for lobster,
shrimp, abalone and other small life. The scientist says that
there is more to this lowly creature than just spines.
To me he is just another complicated tile in the beautiful
mosaic that is the reef world that I so love to visit. As a diver,
I am a bottom dweller. I swim over the bottom and in the cracks,
looking for the strange and colorful creatures that do not swim.
I respect Mr. Urchin or he teaches me.
I went to Florida and swam in the coral gardens there.
Though there were many strange and beautiful creatures there, I
missed Mr. Urchin. Our Captain said that some years back, sadly,
a plague had killed them all.
What would it be like here if Mr. Urchin was gone? I would
miss him. What if most of his neighbors vanished as well. So much
to see on the reef would be gone. So much beauty lost. Well...
That's the way it's going to be. Ecological devastation is
spreading unchecked along the California coast. The Sea Otter is
The Federal Fish and Wildlife Service has announced that they
cannot control the spread of the Sea Otters, even though they
originally promised that they would not be allowed to spread
unchecked. Well, they declared their efforts to relocate otters
outside the legally established range, a failure. I've got to
tell that to a judge. "Well your honor, my foot got too heavy to
hold up, so I failed to avoid speeding".
In this matter the Fish and Wildlife Service has shown less
understanding of ecological principles than a high school biology
student. There is a carrying capacity to any environment for any
specie in that environment. In the otter zone, only so many
otters can survive. You can translocate all the otters from
outside the zone to the center of the zone that you want, but the
zone is not going to support any more than a fairly fixed number
of otters. All species have a limiting factor for their
populations. In otters it is usually food. They do have voracious
appetites. That area they are in will provide only so much food
and no more. Otters die of starvation far more than they are
limited by being eaten by predators.
In this matter the Fish and Wildlife Service has also shown
less than a great memory. Translocation in the ocean has been
tried with nuisance Sea Lions. That was an interesting failure.
Critters like Sea Lions and Otters are quite smart and quite
mobile. They remember places with food and since there is so
much pressure for food in their ecology, they will return to
where they found food, even if it is a long journey. They aren't
completely dumb.
Sea Otters are cute, but they absolutely scour the ecology
where they live. In ways, they are like humans. They are at the
top of the trophic ladder and very generalist. They eat
everything that can be eaten. In an otter area, there are
basically no urchins, scallops, abalone, clams, mussels, cowrys,
moon snails or anything else that the otter can eat. Like humans,
they are capable of destroying the very ecology that their
survival depends on.
Some people suggest that that is the fault of the commercial
harvesters or sport divers. Not so. Humans only harvest a few
species and only abalone, to the extent that otters do. The otter
eats them all. There has never been a purple urchin harvest, but
they are gone from the otter zones. Otters know no size or bag
limit. Otters often bring their food to eat in calm spots behind
rocks. Dive there and the bottom is littered with small broken
mollusk shells.
Dive in an otter area and on the bottom you will see some
stars, anemones, sponges, filter feeders and some other life that
cannot be consumed, but mostly you will see seaweed. The fish do
good, but the curious diverse, colorful invertebrates that we
are used to seeing outside of otter zones, are gone. Rock ledges
actually become scraped clean by repeated otter visits. So much
of the beauty of the reef is gone.

Well, the Fish and Wildlife Service may not understand basic
biological principles, but I do. Let me tell you how it will go.
If the otters expand their range south through the Channel
Islands and south of the California border, bid good-bye to all
private and commercial harvest of shellfish including urchin.
What little the otter leaves will have to be left alone by humans
to prevent extinction of various species. It's hard to say what
will happen to the lobsters, but the habits of otters are such
that you can bet that they will he hit really hard. Otters are
why lobsters are nocturnal.
If otters are allowed to expand past San Francisco into
the north coast abalone, there will be this incredible population
explosion. Then there will be a population implosion as they use
up the available food in just a couple of years. The population
may grow large enough to present an opportunity for a disease to
get a foot hold. That would be interesting. Marine mammals are
quite susceptible to disease. The population might really
collapse then. It appears to already be happening on the Central
Coast. Also the diving will be like it is on the Central Coast,
that is uninteresting and extremely difficult. Due to various
factors, diving on the North Coast will basically end.

It's not just a matter of the otters. The Sea Lions are in
this too. The Marine Mammals Protection Act was written to save
species that were on the brink of extinction. It makes no
provision for when the populations have recovered and is starting
to become a pest. The Sea Lion population is at an all time high,
but when the population naturally collapses, I am afraid that the
Fish and Wildlife Service is just going to claim it is some human
made calamity and even more must be done to protect the species.
Too often, regulatory agencies have created policies that
foster one of two results. Either a specie cannot be harvested or
it ends up being harvested to destruction. Nothing in between.
Even if it is not easy, game management policies must be
formulated that allow for sustainable harvests of wild species.
If the otter spreads unchecked, game management becomes a moot
point as there will be nothing left to manage.
Yes, they are furry and cute, but if a firebreathing dragon
showed up, that would be pretty neat to see too. Once it started
some forest fires, the novelty would wear off quickly. That is
essentially the effect of otters. They will devastate the
existing ecology.

The depressed economic condition of the North Coast is well
illustrated by the large percentage of the housing that is for
sale and the many closed buisnesses. Considering that the
abalone divers probably contribute a fair amount of tourism
dollars to the area, loss of the abalone would be a devestating
blow to the economy of the region.

The only practical solution is going to be to harvest the
otters. Some might be translocated from the fringes of the otter
zone to the middle for genetic diversity, but the zone will only
support so many otters. The only way to stop their spread is
going to be to harvest them. The simplest and most economical
way would be to foster a regulated commercial or private
harvest. These are basic biological principles. How long will it
take for the regulatory agencies to recognize this?.

Personally, I prefer the lowly urchin and all his friends,
over a few hungry otters.

For far more information and documentation of this situation,
see the excellent California Diving web site at www.sonic.net/~rocky

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