KELP COMMUNITY RESTORATION ALONG THE MALIBU COAST

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KELP COMMUNITY RESTORATION ALONG THE MALIBU
COAST
Thomas K. Ford and Heather M. Coleman, UCLA and
Santa Monica Baykeeper
Kelp beds along the Southern California Bight are
primarily dominated by the macroalgal species
Macrocystis pyrifera. These forests provide
critical habitat for approximately 800 species,
comprising nearly one quarter of Californias
endemic marine flora and fauna. An integral part
of the community food web, adult kelp beds
provide vertical complexity and microhabitats,
enhancing rocky reef structure. The presence of
kelp beds alone can increase fish biomass by
300. Kelp beds are intermediately disturbed
habitats with spatial and temporal fluctuations
occurring over time spans of weeks to years.
These natural fluctuations have been replaced by
a prolonged downward trend in kelp canopy area
and standing biomass. Various factors have
contributed to a 40 decline of giant kelp beds
in Santa Monica Bay over the past three decades.
This restoration effort intends to ameliorate the
effects of this loss.
Current and Historic Kelp Populations in the SM
Bay
Point Dume
Palos Verdes
Current Kelp Beds (1989-99)
Historic Kelp Beds (1893-1912)

• Restoration Techniques
• Outplanting laboratory cultured kelp, grown on
  tiles, secured to substrate
• Transplanting dislodged drifting kelp,
  recovered and reattached
• Sporophyll Bags sporophylls removed and
  placed in mesh bags,which are anchored and
  suspended 1m above bottom
• Urchin Relocation relocation of urchins,
  reduced to density of one per square meter

• Site Characterization
• Substrate Surveys Point of contact,
  sampled every 2m, to describe type and size
• Remote Thermal Sensing TidbitTM, deployed on
  bottom to monitor temperature
• Benthic Surveys Invertebrate and algal
  communities assessed, 22 indicator spp.
• Urchin Size Frequencies Test diameter
  approximates age distribution
• Fish Surveys Roving fish counts using REEF
  protocols
• Aerial Surveys Performed by CA DFG, estimates
  kelp canopy area

Results and Discussion   The 1998-1999 El Nino
event had deleterious effects on the kelp beds
off the Malibu coast. These kelp beds failed to
recover within the two-year index determined by
Wheeler North, Ph.D. that typifies healthy kelp
beds. Our restoration efforts attempt to advance
the recovery of these areas, correct certain
ecological imbalances, and promote the long-term
sustainability of these once thriving
communities. The data suggest that juveniles
have matured into sub-adults and subsequently
adults in the 1.5 years that we have monitored
these sites. The decrease in adult densities can
be attributed to greater individual plant size
and canopy formation. Concordant with canopy
development is occlusion of light, resultantly
large adults shade out their lesser neighbors and
strongly deter recruitment. We will continue to
restore adjacent areas and monitor this section
of reef for the following five years. At that
time more conclusive results will be drawn from
these efforts and compared to the progression of
unaided kelp in Malibu.
Photo by Nancy Caruso
Contributors Ladan Mohajerani, Brendan Reed,
Chantal Collier, Laura Butler,Julie Barr, Terry
Tamminen, Baykeeper Volunteers
Acknowledgements NOAA, CA DFG, CA State Lands
Commission, CA Coastal Commission, Army Corps of
Engineers, CA Coastal Conservancy, Santa Monica
Bay Restoration Commission, Environment Now,
National Park Service Channel Islands, Catalina
Coastal Conservancy, City of Santa Monica, Los
Angeles Regional Water Quality Control Board,
Lincoln Middle School