Identifying Ecosystem Boundaries
Carrie Kappel, Mike Fogarty, Rebecca Martone

Ecosystem based management is fundamentally place-based management. It begins with
the goal of managing and protecting a particular ecosystem. Therefore, one of the first
steps in implementing ecosystem-based management is to define the ecosystem of
interest by outlining its boundaries. However, geographical boundaries of ecosystems
depend on the scale considered and may also be variable in time, shifting seasonally or
under changing climatic conditions. In order to define ecosystem boundaries for the
purposes of management, one must decide on the scale(s) of interest, and then determine
the biophysical (and in some cases socioeconomic) characteristics of ecosystems and
their natural variability, recognizing that any defined system is necessarily nested within
larger scale ecosystems and processes and contains smaller scale ecosystems and
processes.

Approach
We tentatively plan to use nearshore coastal Central California as a case study to develop
approaches to define ecosystem boundaries and address some of the cross-cutting issues
in EBM, such as spatial scales of processes and management, integration of datasets
collected at varying spatiotemporal scales, and coping with uncertainty in data. We
recognize that the nearshore environment and the Central Coast region are both nested
within larger systems and to a large degree are open to inputs and processes that will
cross the boundaries we specify as potential management units. For some applications, it
will be necessary to account explicitly for these “open” boundaries. During the boundary
delineation exercise we will consider the implications of processes occurring at larger
spatial scales and will examine the sensitivity of our results to alternative definitions of
the spatial extent of the analysis. This case study was deemed appropriate because of its
nested spatial scales, the quality of data available, existing interest in EBM within this
area and from the agencies with jurisdiction. We have been gathering existing empirical
data on this potential case study and will meet with managers from the areas to solicit
their expertise and advice on key management objectives, target ecosystem services, and
critical ecosystem linkages for their system.

Example questions we hope to address:
• How should the boundaries of ecosystems be defined? What constitute coherent,
  natural units for management within Central California?
• What are the best techniques for integrating datasets that derive from diverse
  disciplines and have been collected at varying resolutions and spatial scales? How can
  one account for the joint uncertainties associated with integrated data layers and
  incorporate them into models?
• How can we incorporate temporal variability and how does this variability affect the
  definition of boundaries? Does this differ at different scales?
• How can boundary definition be addressed in systems with less data? Can we use this
  technique to help prioritize data collection at different scales?
Using a GIS framework integrated with multivariate statistical approaches, we will
provide a framework for managers to approach ecosystem boundary definition. Below is
a step-by-step outline of our process:

  -  Compile physical and biological data layers and accompanying metadata for the
    State of California (see Data layers for EBM boundary delineation.xls)
  -  Import data layers into ArcGIS
  -  Decide on the scale of resolution for the analysis (e.g. 1.25 km grid) based on the
    datasets
  -  Interpolate point data (using kriging or other geospatial tool) to create raster
    layers
  -  Perform PCA on raster data to reduce variables
  -  Perform cluster analysis on eigenvectors from the PCA

Example analyses:
  1. Test how using this model with limited data will affect boundaries. Which data
   layers tend to drive variation among cluster outputs?
  2. Test how ratcheting the uncertainty up or down will affect our ability to define
   boundaries.
  3. Test how temporal variability (e.g seasonal or annual changes in kelp cover or
   fish diversity) affects boundary delineation using maps of temporal variance.
  4. Test uncertainty and data inclusion at different scales.

Questions for the group:
  1. What spatial resolution would be most appropriate?
  2. Are there existing analyses similar to this that we should know about?
  3. Are there other data layers that should be included?
  4. Are there novel questions that we could answer using this approach that we have
    not considered yet?
         Data layer                                        Coverage                        Spatial resolution    Temporal resolution        Continuous or categorical
Data category                       Source                                                                                              In hand?
Bathymetry
        Bathymetry                                         statewide                       10 m contour intervals
                             http://marinemap.org/mlpa/viewer.htm                                                                               Y
Substrate & Habitat type
        Benthic rugosity 200m                                   statewide                       200 m grid        -
                             http://marinemap.org/mlpa/viewer.htm                                                                               Y

         Benthic rugosity 5m                                    Central California (MLPA Central Coast study region)  5 m grid         -                 Cat: low, med, high
                             http://marinemap.org/mlpa/viewer.htm                                                                               Y
         Seafloor type (soft vs. hard bottom)                           statewide                                                     Cat: soft, hard
                             http://marinemap.org/mlpa/viewer.htm                                                                               Y
         Coarse scale habitat type (also avail.
         intersected with MLPA depth zones
         and canyons)                                       Central California (MLPA Central Coast study region)  ?            -                 Cat: multiple habitat types
                             http://marinemap.org/mlpa/viewer.htm                                                                               Y
         Fine scale habitat type (also avail.
         intersected with MLPA depth zones
         and canyons)                                       Central California (MLPA Central Coast study region)  1:5000 scale       -                 Cat: multiple habitat types
                             http://marinemap.org/mlpa/viewer.htm                                                                               Y

         Southern California Rocky Substrate http://marinemap.org/mlpa/viewer.htm         Southern California                  1:125000         -                 Cat: rock           Y
         Southern California Sediment                               Southern California                  1:125000         -                 Cat: sediment
                           http://marinemap.org/mlpa/viewer.htm                                                                                  Y
Kelp
         Kelp coverage                                       statewide                                    1989, 1999, 2002-2004
                             http://marinemap.org/mlpa/viewer.htm                                                                               Y
                                                                                              3 out of 4 of: 1989, 1999, 2002,
         Persistent kelp                                      statewide                                    2003
                             http://marinemap.org/mlpa/viewer.htm                                                                               Y
                                                      9 reef sites on mainland coast of SB Channel and 2   point data (transects                    Cont: number of fronds,
        Kelp abundance                                       sites on N side of Santa Cruz Is.           and quadrats)      2000-2005             holdfast diameter       Y
                           SBCLTER
Fish and benthos
        Fish diversity and abundance (spatial
        subset of data from NMFS trawl
        surveys, from N-Central CA
        biogeographic analysis, all years in
        one layer)                                         Point Arena to Point Sal                point data (from trawls) summer-fall (1977-2001)      Cont
                           http://marinemap.org/mlpa/viewer.htm                                                                                 Y
        Commercial fish landings (sp.
        Specific)                                         Statewide by Port                   Regional (by port)    1928-2003, monthly/annual     Cont
                           http://www.pfeg.noaa.gov/products/las.html
                                                                                 Fishing location/Diver
         Sea urchin fishery landings                                Southern California                  by Region (N & S)    1991-2003 annual          Cont (CPUE & value)
                             http://www.dfg.ca.gov/Mrd/seaurchin/index.html
         Commercial fish landings (sp.
         Specific)                                         Statewide by Port                   Regional (by port)    2001-2004 monthly         Cont (CPUE & value)
                             http://www.dfg.ca.gov/Mrd/fishing.html

                                                      9 reef sites on mainland coast of SB Channel and 2   point data (transects                    Cont: % cover UPC, species
         Sessile spp percent cover UPC                               sites on N side of Santa Cruz Is.           and quadrats)      2000-2005             and/or fxn grps and substrate Y
                             SBCLTER

                                                      Central California (Santa Cruz (Sandhill) to Oxnard  point data (transects                   Cont: % cover UPC, species Y (need to
         Sessile spp percent cover UPC                               (Naples) plus the Channel Islands (to SBI)       and quadrats)      1999-2005             and/or fxn grps and substrate download)
                             PISCO
                                                                                                                              Summary
                                                      88 sites from Santa Cruz to San Diego (including    point data (transects                   Cont: % cover UPC, species (Not in GIS
         Sessile spp percent cover UPC                               Channel Islands)                    and quadrats)                     2004 and/or fxn grps and substrate layers)
                             CRANE
                                                      9 reef sites on mainland coast of SB Channel and 2   point data (transects
         Invert and algal density swaths                              sites on N side of Santa Cruz Is.           and quadrats)      2000-2005             Cont: counts by spp      Y
                             SBCLTER
                                                      Central California (Santa Cruz (Sandhill) to Oxnard  point data (transects                                   Y (need to
         Invert and algal density swaths                              (Naples) plus the Channel Islands (to SBI)       and quadrats)      1999-2005             Cont: counts by spp      download)
                             PISCO
                                                                                                                              Summary
                                                      88 sites from Santa Cruz to San Diego (including    point data (transects                                   (Not in GIS
         Invert and algal density swaths                              Channel Islands)                    and quadrats)                     2004 Cont: counts by spp      layers)
                                                                                 point data (40 x 2 m
                                                      9 reef sites on mainland coast of SB Channel and 2   swath transects,                      Cont: counts by spp and
         Fish abundance                                      sites on N side of Santa Cruz Is.           midwater and benthic)  2000-2006             length of each indiv     Y
                             SBCLTER
                                                                                 point data (40 x 2 m
                                                      Central California (Santa Cruz (Sandhill) to Oxnard  swath transects,                      Cont: counts by spp and    Y (need to
         Fish abundance                                      (Naples) plus the Channel Islands (to SBI)       midwater and benthic)  1999-2005             length of each indiv     download)
                             PISCO
                                                                                 point data (40 x 2 m                                   Summary
                                                      88 sites from Santa Cruz to San Diego (including    swath transects,                      Cont: counts by spp and    (Not in GIS
         Fish abundance                                      Channel Islands)                    midwater and benthic)                 2004 length of each indiv      layers)
                             CRANE
         Data layer                                      Coverage                         Spatial resolution  Temporal resolution       Continuous or categorical
Data category                     Source                                                                                            In hand?
Seabirds
                                                                                            1975-1997 (avail divided into
                                                                                            warm, cold, and neutral water
                                                                                            periods or Davidson Current
                                                                                            Season vs. Oceanic Season vs.
         Bird density                                     Northern and Central California              5' grid       Upwelling Season)        cont: 76 species
                            http://marinemap.org/mlpa/viewer.htm                                                                             Y
                                                                                            1975-1997 (avail divided into
                                                                                            warm, cold, and neutral water
                                                                                            periods or Davidson Current
                                                                                            Season vs. Oceanic Season vs.
         Bird diversity                                    Northern and Central California              5' grid       Upwelling Season)        cont: Shannon-Wiener Index
                            http://marinemap.org/mlpa/viewer.htm                                                                             Y
                                                                                            1984, 2001(avail divided into
                                                                                            warm, cold, and neutral water
                                                                                            periods or Davidson Current
                                                                                            Season vs. Oceanic Season vs.
       Bird biomass density                                   Northern and Central California              5' grid       Upwelling Season)        cont: 76 spp, kg/km2
                            http://marinemap.org/mlpa/viewer.htm                                                                             Y
       Bird breeding colonies                                  Northern and Central California              point data      1980, 2000, updated w/ 2002
                            http://marinemap.org/mlpa/viewer.htm                                                                             Y
       Bird colonies with counts by species                                                                                   cont: counts by species or
       (MMS survey)                                       statewide                         point data                    1980 presence/absence
                            http://seamap.env.duke.edu/datasets/detail/271                                                                        Y
Marine mammals
       Marine mammal haulouts                                  statewide                         point data                    2002
                            http://marinemap.org/mlpa/viewer.htm                                                                             Y
       Marine mammal rookeries                                  statewide                         point data                    2002
                            http://marinemap.org/mlpa/viewer.htm                                                                             Y
       Marine mammal counts                                   statewide                         point data                    1991 cont: counts by species   Y
                            http://seamap.env.duke.edu/datasets/detail/271
       Sea otter counts                                     Golden Gate to Santa Barbara               0.5 km intervals   2001, 2002            Cont: counts
                            http://marinemap.org/mlpa/viewer.htm                                                                             Y
       sea otter linear densities                                Golden Gate to Santa Barbara               10 km segments    2001-2002            Cat: low, med, high
                            http://marinemap.org/mlpa/viewer.htm                                                                             Y
Zooplankton
                                                    CalCOFI cruise locations and interpolated data,
                                                    statewide in earlier years, Southern California in more
         Zooplankton biomass                                  recent years                       point data      1951-1998, at least quarterly
                            CalCOFI
Temperature
                                                    CalCOFI cruise locations and interpolated data,
                                                    statewide in earlier years, Southern California in more
         Temperature                                      recent years                       point data      1949-2005, at least quarterly
                            CalCOFI
                                                    24 grid stations and 7 trans-channel stations in Santa
         Temperature                                      Barbara Channel and around Channel Islands        point data      2001-2003 (have 2003 data only) Cont             Y
                            SBCLTER
                                                                                            1,3,8,14 day composites from
         SST                                                                       1.25 km       2006, archives elsewhere    Cont             N
                            AVHRR http://las.pfeg.noaa.gov/oceanWatch/oceanstatewide
                                                                                                                           Y (need to
         Ocean temperature                                   statewide                         0.1 degree      monthly or 8 day (1985-2003)   Cont             download)
                            SeaWIFS
Salinity
                                                    CalCOFI cruise locations and interpolated data,
                                                    statewide in earlier years, Southern California in more
         Salinity                                       recent years                       point data      1949-2005, at least quarterly
                            CalCOFI
                                                    24 grid stations and 7 trans-channel stations in Santa
         Salinity                                       Barbara Channel and around Channel Islands        point data      2001-2003 (have 2003 data only) Cont             Y
                            SBCLTER
Water chemistry
                                                    CalCOFI cruise locations and interpolated data,
                                                    statewide in earlier years, Southern California in more
         Phosphate                                       recent years                       point data      1949-2005, at least quarterly  Cont
                            CalCOFI
                                                    CalCOFI cruise locations and interpolated data,
                                                    statewide in earlier years, Southern California in more
         Oxygen                                        recent years                       point data      1949-2005, at least quarterly  Cont
                            CalCOFI
                                                    24 grid stations and 7 trans-channel stations in Santa
        Oceanic constituents                                  Barbara Channel and around Channel Islands        point data      2001-2003 (have 2003 data only) Cont             Y
                            SBCLTER
Primary productivity
                                                    24 grid stations and 7 trans-channel stations in Santa
         Surface and water column NPP                             Barbara Channel and around Channel Islands        point data      2001-2003 (have 2003 data only) Cont             Y
                            SBCLTER
                                                    CalCOFI cruise locations and interpolated data,
                                                    statewide in earlier years, Southern California in more
         Chlorophyll                                      recent years                       point data      1983-2005, at least quarterly  Cont
                            CalCOFI
         Chlorophyll                                      statewide                         1.25 km
                            MODIS on Aqua
                                                                                                                           Y (need to
         Chlorophyll                                      statewide                         0.1 degree      monthly or 8 day (1997-2005)   Cont             download)
                            SeaWIFS
         Primary productivity (derived from                                                                                                 Y (need to
         SeaWIFS Chl a)                                    statewide                         0.1 degree      monthly(1997-2005)        Cont             download)
                            SeaWIFS
Upwelling
         Upwelling index                                    15 locations along California Current           point data
                            http://www.pfeg.noaa.gov/products/las.html