What Happened to the Kelp in Southern California

What you are seeing now when you dive the southern Channel Islands, and
by that I mean San Clemente, Santa Catalina, San Nicholas and Santa
Barbara is not our typical regime.  The southern island marine
ecosystems have been devastated by the combined wrath of long-term sea
water heating and what is now regarded as the greatest El Nino on
record.  Scientists at Scripps have confirmed a continued rise on ocean
temps over the last decade.  We had a mini El Nino in 92-93 prior to the
mother of all El Ninos 97-98.  Previous to this was the 1983 El Nino
which was the “Mother of All” prior to the 97-98 ENSO (“El Nino Southern
Oscillation”).   We at the California Conservancy Divers have ringed
Catalina Island with thermographs since 1992 and have the last two events
on record as far as Catalina goes.  The combined assault of warm water on
our kelp forests has devastated our nearshore resources.

As I have been diving SoCal for over 30 years I have a historic
perspective that includes plenty of diving prior to 1983.  Prior to then
the lee side of Catalina was home to a fringing kelp forest similar to
the one on the lee of San Clemente.  Since 1983, that kelp has been in
decline and completely disappeared in 1983 and 1997-98.  After the 1983
ENSO the kelp never recovered its former range or vitality.  Santa
Barbara Island was surrounded by an extensive forest.  For years it was
virtually impossible to travel by boat between Webster Point and Arch
Reef which lies 1/2 mile offshore, the kelp canopy was just too thick. 
Like Catalina, SBI never rebounded from the 1983 event and since then,
the purple urchin hordes have turned most of the island into a urchin
barren devoid of kelp.  (I wonder if the harvest of all the Red Urchins
(S. franciscanis), had anything to do with the Purple Urchin (S.
purpuratus) horde we now find in many of our southern forests?

The 1997-98 ENSO warmed water so long and so deep that virtually all of
our giant kelp disappeared.  Giant Kelp dies when water temps rise above
68 degrees F.  When the kelp died everything that lived in those forests
suffered.  Where is a Giant Kelp fish to go when there is no kelp? 
Ditto for the Kelp Crabs and dozens of other vertebrates and
invertebrates that live in or use the forests for food or shelter.  When
the kelp was gone all of our site-attached reef fishes had no cover. 
They are not migratory such as the Yellowtail or Bonita and had nowhere
to run.  Virtually all of our large male Sheephead are gone, shot by
recreational divers.  The remaining population is being strip-mined by
the fastest growing fishery in California, the live fish fishery
catering to Oriental retailers and restaurants.  Ditto for our Moray
Eels which do not even breed in these waters according to most
scientists.  There are a host of other horror stories but that is the
bad news.

The good news is that our kelp will recover to a great extent.  It
already started this year and was put on hold when summer waters
warmed.  Within 1-2 years the kelp beds will recover to some extent but
the critters that live there will be long in recovering their former
populations.  Give us 5 or 6 years.  Meanwhile, if you want to dive in
SoCal there are some interesting side benefits.  For once, you can see
the reef in all its glory without the kelp in the way.  I have found a
lot of caves that were not visible before.  That makes for some
interesting viewing and a perspective that was not available when
visibility was limited by kelp.  Lobster season starts this next Friday
night and all indications are for another fine year.  Last year was a
banner year for the divers and commercial lobster trappers.  This year
looks like a repeat and we sportdivers get a 4 day head start before the
commercials are allowed to bait their traps.   If you really want to
dive SoCal in all its glory the best bet is to dive the northern Channel
islands, especially Santa Rosa and San Miguel.  Miguel has recovered
much faster than the other islands and appears lush when compared to the
other southern islands.

We will see about the long term but I would hate to see our southern
Channel Islands reduced to the level of despair that you will see if you
dive the Pt. Loma Kelp beds in San Diego or the Coronado Islands in
Mexico.  If the warm water continues and we do nothing to stop the
unregulated strip-mining of our forests by commercial interests it is
quite likely that SoCal will start looking like Pt. Loma and the
Coronados.  Then, if we want to dive in the kelp like it used to be we
will have to travel to San Miguel or Monterey to have it like it was.

I hope the warming does not increase and you will be able to enjoy all
the fine diving in the south I have been writing about all these years
some day soon.

Steve Benavides  September 26, 1998

Stephen G Benavides©1998
All Rights Reserved