Full Booklet

what is
PISCO The Partnership for Interdisciplinary Studies of Coastal Oceans is a longterm program of scientific research and training dedicated to advancing the
understanding of the California Current Large Marine Ecosystem along the U.S.
West Coast. PISCO is pioneering an integrated approach to studying this complex,
rich, and economically important environment.
PISCO is distinguished by its interdisciplinary approach, large geographic extent,
and decades-long time frame. PISCO conducts monitoring and experiments along
more than 1,200 miles (2,000 kilometers) of coastline, as well as laboratory and
theoretical studies. The research incorporates oceanography, ecology, chemistry,
physiology, molecular biology, genetics, and mathematical modeling to gain novel
insights into systems ranging from individual animals and plants to the whole
ecosystem.
PISCO’s findings apply to conservation and resource management issues. PISCO
scientists participate in local, regional, national, and international initiatives for
marine environmental planning. Through its university courses, PISCO helps to
train the next generation of scientists in interdisciplinary approaches to marine
research and policy.
Established in 1999 with funding from The David and Lucile Packard Foundation,
PISCO is led by scientists from Oregon State University (OSU), Stanford
University’s Hopkins Marine Station, University of California at Santa Cruz
(UCSC), and University of California at Santa Barbara (UCSB). As of 2005, core
PISCO activities are funded by collaborative grants from The David and Lucile
Packard Foundation and the Gordon and Betty Moore Foundation. The core
support and additional funding from diverse public and private sources
make this unique partnership possible.
PISCO
Coastal Connections
Volume 5
Table of Contents
1
View from the Wave Crest
2
Patterns of Change
Reproductive Hotspots
Fish Population Genetics
Physics of Rocky Shores
Identifying Fish Birthplaces
6
Oceanographic Frontiers
Monitoring Oceanography
Modeling Drifting Young
Currents and Dispersal Paths
10 Ecological Linkages
Changes in Kelp Forests
Oceans Affect Shore Ecology
Effects of Climate Warming
14 Interdisciplinary Training
& Research
PISCO Training Courses
Student Showcase
16 Sharing the Science
Teaching Groups to Monitor
PISCO Advises California
Straight Talks on Fishing
Methods of Stock
Assessment
View from the Wave Crest
P
ISCO Coastal Connections is an
annual publication of the Partnership for
Interdisciplinary Studies of Coastal Oceans
(PISCO). We welcome you to the fifth issue in the
series that highlights major findings, research projects,
as well as outreach and education.
The interdisciplinary PISCO consortium is an interconnected group of established scientists and postdoctoral fellows, science and policy coordinators, data
managers, graduate students, and research technicians. The consortium’s work
is further strengthened by its collaborations with government agencies, nongovernment organizations, and academic institutions. This issue of PISCO
Coastal Connections reflects these cumulative efforts and their value for marine
policy and management.
Articles in this year’s “Patterns of Change” section feature some of our latest
findings about variations over time and distance in the marine ecology and
oceanography of the U.S. West Coast. “Oceanographic Frontiers” describes
PISCO’s extensive ocean-observing network and our research into oceanographic processes in coastal waters. The “Ecological Linkages” section explores
new findings about the connections between oceanography and ecological
changes. Results from PISCO’s graduate student programs, including our new
marine policy course, are highlighted in “Interdisciplinary Training.” “Sharing
the Science” showcases examples of PISCO’s initiatives to communicate scientific findings and methods to broader audiences.
We invite you to enjoy this issue of PISCO Coastal Connections and the
achievements described on the following pages.
PISCO Coastal Connections Program Coordinator:
Kristen Milligan
PISCO Coastal Connections Coordinators:
Satie Airamé, Liz Riley, Cinamon Vann,
Amy Windrope
Editor & Writer: Peter H. Taylor
Creative Director: Monica Pessino
Graphics Assistant: Julia Kwinto
GIS Support: Will McClintock
Line Drawings: Linda D. Nelson
Cover photo: Painted greenling (Oxylebius pictus)
© 2006 Luke Miller. Cover photo insets, top
to bottom: Wyatt Patry, Francis Chan, Jane
Lubchenco, Monica Pessino. Opposite page
photos, left to right: Gretchen Hofmann,
Giacomo Bernardi, Luke Miller, Amy Wagner
PISCO Coastal Connections is a publication of
the Partnership for Interdisciplinary Studies of
Coastal Oceans (PISCO). Contents © 2006.
For more information about PISCO or to join
the mailing list for future publications, please
contact the consortium at the addresses listed
on the back cover.
PISCO principal investigators (top to bottom, left to right): Libe Washburn (UCSB), Pete Raimondi (UCSC), Steve
Gaines (UCSB), Mark Denny (Stanford), Margaret McManus (UCSC), Jane Lubchenco (OSU), Jack Barth (OSU), Robert
Warner (UCSB), Steve Palumbi (Stanford), George Somero (Stanford), Mark Carr (UCSC), and Bruce Menge (OSU).
Not shown: Gretchen Hofmann (UCSB). Photo: Satie Airamé
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Geographic Differences in Barnacle Reproduction
In monitoring surveys, PISCO scientists found that barnacles living on the
coast near Cape Perpetua, Oregon, produced approximately five times as
many offspring as barnacles near Cape Foulweather, Oregon. This reproductive
difference may arise from differences in food availability. The waters near
Cape Perpetua contain much more phytoplankton, one of the barnacles’
major foods. In targeted experiments, the scientists uncovered even greater
differences, as Cape Perpetua barnacles produced 120 times more young than
barnacles from Cape Foulweather (see figure above). Other marine species
are likely to have reproductive hotspots, and identifying these hotspots could
improve management of marine ecosystems (see article, next page).
OF
patterns change
Hotspots for
M
Reproduction and Conservation
arine scientists have
long suspected that populations of
invertebrates living in different places
in the sea may differ in their production of
young, but scientists have rarely tested this idea
empirically. Using the acorn barnacle (Balanus
glandula) as a model, PISCO/OSU doctoral student Heather Leslie
Barnacles (Balanus glandula) on the rocky shore.
Photo: Sheri Etchemendy
Science of Marine Reserves
Marine reserves offer greater protection than any other type of marine
protected area (MPA) by completely
protecting animals, plants, and their
habitat from removal or alteration.
Other MPA designations may allow
certain human uses, like recreational
fishing. Design of marine reserves and
other protected areas can be informed
by scientific research regarding species
distributions, abundance, dispersal,
population replenishment, and interactions with other species. Research
shows that marine reserves can help
to protect marine habitats and species,
and in some cases restore populations
of depleted species. Fish, shellfish, and
seaweeds inside marine reserves tend
to be larger, more abundant, and more
diverse than they are in non-reserve
areas. These benefits of marine reserves
can boost marine ecosystem resilience
and productivity. For more information
about the science of marine reserves,
visit www.piscoweb.org.
examined geographic variation in barnacle reproduction along the Oregon
coast to find out whether food supply affected the number of offspring
produced. Her research builds on PISCO’s prior findings that phytoplankton,
which barnacles eat, are abundant near Cape Perpetua but scarce near Cape
Foulweather. Leslie’s research offers an example of how marine scientists
can effectively gather information on spatial variation in reproduction and
link it to ecological and oceanographic processes. Leslie collaborated on the
research with PISCO principal investigators Jane Lubchenco and Bruce Menge,
postdoctoral fellow Francis Chan, and OSU honors student Erin Breck.
The research highlights the value of understanding how ecological and
oceanographic processes influence marine populations. Apparently similar
habitats along the coast differ markedly in their ecological functioning (see
findings, opposite page). Particular sites may be especially significant sources
of young for some marine invertebrates, serving as reproductive hotspots.
Leslie’s findings are relevant to design of marine protected areas because they
suggest the potential to identify and conserve sites with high reproductive
rates for certain species.
Heather Leslie is now a postdoctoral fellow at Princeton University.
Publication: Barnacle reproductive hotspots linked to nearshore ocean conditions. Proceedings of
the National Academy of Sciences 102 (2005): 10534–10539.
Heather Leslie studying barnacle reproduction at Fogarty Creek, along the Oregon coast. Photo: Jane Lubchenco
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Genetics Show Distinct Rockfish Populations
PISCO/UCSC graduate student Martha Burford is studying geographic variation in the population genetics of blue rockfish (Sebastes mystinus) and kelp
rockfish (S. atrovirens) along the California coast. Adult rockfishes generally do
not travel far from the kelp beds and rocky reefs where they live. However,
long-distance dispersal of their young might link the state’s rockfishes into one
genetically similar population. Burford uses genetic markers, called microsatellite loci, to detect genetic differences among adults and juveniles of both
species. Her research reveals substantial geographic variation in the population
genetics of juvenile rockfishes in California’s waters, indicating that the state
has multiple genetically distinct populations. Burford’s findings have implications for fisheries management. For example, a network of several marine protected areas or marine reserves might protect the genetic diversity of rockfish
better than one large area.
Caption
Finding Shelter on the Rocks
4
Martha Burford prepares DNA from blue rockfish for
analysis. Photo: Lydia Bergen
PISCO/Stanford graduate student Michael “Moose” O’Donnell explored the fluid
mechanics of wave-battered shores to understand how topography affects
ecological patterns. His research revealed that crevices on rocky shores do not
necessarily protect invertebrates and seaweeds from pounding waves—and
may, in fact, do the opposite. Depending on size and orientation, a crevice
can funnel water, creating intense wave forces. Yet, in some cases, snails,
seaweeds, and other shore-dwelling species actually benefit from the stronger
wave forces, as water splashing from the crevices enables them to live higher
on the rocks than they otherwise could. In contrast, O’Donnell has found that
mussel beds do create shelter for small animals. Wave forces experienced by
a snail, for example, drop by 40 percent within 10 centimeters of a mussel
bed—and by 90 percent within one centimeter. This research provides insight
into how components of the physical environment interact to create habitable
space for marine animals and plants along the coast.
Michael O’Donnell is now a postdoctoral fellow at the University of California,
Santa Barbara.
O’Donnell measures wave forces in mussel beds.
Photo: Luke Miller
crevice
Green box indicates location of close-up photo (left).
Photo: Michael O’Donnell
O’Donnell has found that rocky crevices can increase the wave forces experienced by marine animals and seaweeds.
Heights of bars indicate wave forces measured by wave-force recorders (white balls below bars). When a two-meter
wave hits, the force in a small crevice (red bars) can be double that outside the crevice (orange and green bars).
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patterns of change
PISCO/UCSB scientists collected larval kelp rockfishes from three areas near Santa Barbara and analyzed the trace elements in the fishes’ otoliths, or ear bones. They measured seven
elements: strontium (Sr), barium (Ba), lead (Pb), magnesium (Mg), manganese (Mn), iron (Fe), and zinc (Zn). Because the relative amounts of the elements varied from site to site, the
trace elements acted as distinctive tags identifying where each fish was born.
Deciphering the Tags
Natural Tags Indicate Fish Birthplaces
Trace elements are incorporated from
ocean water into a fish’s ear bone, or otolith, as it grows. The otolith grows by adding calcium layers, like rings in a tree. Trace
elements vary among places in the ocean,
so as the fish travels, these differences
are recorded in the otolith layers. PISCO
scientists use lasers and mass spectrometers to measure the trace elements in the
layers. By matching the layers’ signatures to
particular places in the ocean, the scientists intend to use the otolith like a natural
“flight recorder” of where a fish was born
and where it traveled. For more information about the technique, see PISCO Coastal
Connections, Volumes 1 to 4.
PISCO/UCSB scientists have discovered that water chemistry along the open
coast varies enough to leave identifiable chemical signatures in the otoliths, or
ear bones, of newborn kelp rockfishes (Sebastes atrovirens). These signatures
may prove to be useful as natural “tags” that identify the birthplaces of rockfishes caught as adults.
The scientists collected larval rockfish from three areas along the mainland and
islands near Santa Barbara. The scientists removed otoliths from the tiny fish
and analyzed the chemical composition using mass spectrometry (see sidebar).
They found detectable levels of several trace elements in the otoliths, and the
chemical signatures varied in a way that was distinctive among the study sites
(see figures and caption).
Results suggest that otoliths could be used to identify the birthplace of adult
rockfishes, after geographic and temporal patterns in otolith signatures along
the coast are understood. Ultimately this method could reveal the connections
among fish populations, enabling better fisheries management.
Researchers are Jennifer Caselle, Georges Paradis, Michael Sheehy, and Robert
Warner (PISCO/UCSB); and Stephen Swearer (University of Melbourne, Australia).
Publication: Natal trace-elemental signatures in the otoliths of an open-coast fish. Limnology and
Oceanography 50(2005): 1529–1542.
Kelp rockfish (Sebastes atrovirens). Photo: Marc Chamberlain
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Network of Oceanographic Moorings
Locator Map
NMS = National Marine
Sanctuary
SBC-LTER = Santa Barbara
Coastal Long-Term
Ecological Research
PISCO scientists are working to identify how oceanographic conditions help shape coastal ecosystems.
To study the marine environment near shore, PISCO deploys and maintains dozens of oceanographic
moorings from Oregon to southern California. Partnerships with the National Oceanic and Atmospheric
Administration’s (NOAA’s) National Marine Sanctuaries (NMS) program and the National Science
Foundation’s Santa Barbara Coastal Long-Term Ecological Research Program (SBC-LTER) enable greater
coverage and expertise. PISCO’s database experts and scientists are developing new systems to manage
the vast amounts of oceanographic data from PISCO moorings. The data are available by contacting PISCO
staff, or through online data catalogs at www.piscoweb.org.
oceanographic
frontiers
Monitoring Detects Ocean Anomalies
Oregon
Central California
I
n early summer 2005, many people
began to notice unusual changes along the North
American west coast—warmer ocean temperatures
near the shore, decreased concentrations of plankton
in some coastal waters, a drop in groundfish catches, and an
increase in dead seabirds found on beaches.
A delay of nearly two months in the onset of normal springtime, southward
winds resulted in little or no upwelling of cold, nutrient-rich deep waters.
This led to warm surface waters, scarce nutrients, and lowered productivity
along the coast. During this apparently anomalous event, PISCO researchers
detected unusual ocean conditions and consequent ecological impacts.
•
Warmer water (figure, left) – Most pronounced in Oregon during the
late spring, the water reached 18 degrees Celsius—5 to 7 degrees above
normal. Coastal waters of California were 1 to 3 degrees Celsius warmer
than normal early in 2005.
Southern California
•
Changes in phytoplankton – Surveys in Oregon found approximately
half as much phytoplankton in May and June as in previous years. In Monterey Bay, a shift occurred in the phytoplankton; dinoflagellates dominated
in summer 2005, whereas diatoms were dominant in 2002 (Jim Sullivan,
University of Rhode Island).
•
Red lines on the graphs indicate average daily water temperatures on the ocean surface in 2005 at PISCO moorings. Blue lines show the averages for 2001 to 2004 and
variation around this average. When the red line is above
or below the blue region, temperatures in 2005 differed
significantly from previous years. Moorings in Oregon are
deployed only from spring to fall each year because of
intense winter storms; therefore data are not available for
winter and early spring months.
Low population replenishment and larval abundance – Mussel
population replenishment was the lowest ever observed in Oregon for at
least the last decade. Along the central coast of California, six species of
rockfish failed to add young to their populations in kelp forests. Offshore
surveys by NOAA revealed very few larvae.
PISCO scientists are now working with researchers at other institutions to
evaluate the ecological impacts of the unusual period of warm water.
PISCO researchers are Jack Barth, Francis Chan, Anthony Kirincich, Jane
Lubchenco, Bruce Menge (OSU); Mark Carr, Patrick Drake, Margaret McManus,
Pete Raimondi (UCSC); Jennifer Caselle, Chris Gotschalk, Libe Washburn (UCSB).
The Cause: Delay in Southward Winds
Unusual wind patterns were the driving force behind major ecosystem anomalies along
the Oregon coast in 2005. PISCO/OSU researcher Jack Barth and OSU researchers Steven
Pierce and Renato Castelao analyzed wind records from the last 20 years for comparison with 2005. Southward winds drive the upwelling of cold, nutrient-rich waters to the
ocean surface. One measure used by researchers to determine the onset and magnitude
of upwelling is called “cumulative wind stress.” The figure (right) shows cumulative southward wind stress (negative values) as measured from an offshore NOAA buoy. Normally,
these winds blow strongly enough for upwelling to fuel the coastal food web through the
summer. In 2005, upwelling was delayed by about two months due to lack of favorable
winds. From June to July 2005, cumulative wind stress was the least ever observed in the
past 20 years. In late July 2005, upwelling-favorable wind stress finally reached more typical
conditions, but then it went into overdrive with more persistent upwelling than normal. By
mid-September, the total amount of upwelling caught up to the historical average—but it
was too late for the fish, birds, and other species that rely on upwelling during summer.
The graph (right) shows the 20-year average (black line) for cumulative wind stress and
the variation around this average (shaded); the blue line indicates conditions in 2005.
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Modeling Dispersal of Young Fish
Lines indicate dispersal trajectories of barnacle young in the oceanographic model. Stars indicate points on the shore
where young were released in the models. During upwelling conditions, young tended to be carried southward and
away from shore (black lines). During periods without upwelling, called “relaxation,” more young were retained and
moved to the shoreline (red lines).
Models Link Oceanography and Animal Behavior
8
Because many fish and invertebrate species release their young into the water
to spend weeks or months drifting, the dispersal of young serves as an important link among populations. A major goal of PISCO is to understand the
interconnections of fish and invertebrate populations. Tracking the tiny young is
extremely difficult, so PISCO is developing numerical models, based on oceanographic and ecological data, to simulate the dispersal. Such models traditionally
treat the young as passive, drifting particles. Yet the young of many species
actively regulate their depth in the water, moving upward or downward over
time. Currents move in different directions and speeds at different depths, so
this behavior can affect the path of dispersal.
PISCO is working to integrate the behavior of young invertebrates and fish into
dispersal models to better mirror actual conditions. Scientists at PISCO/UCSC
have created a model for Monterey Bay that combines physical oceanographic
data with information on barnacle larval growth and behavior. The coupled
physical-biological model simulates current speeds and directions throughout
the bay at various depths. During the simulation, the model releases barnacle
larvae at points along the coast and then tracks them as they drift. The larvae in
the model change depth with each developmental stage, just as real barnacle
larvae do. Taking into account each larva’s depth over time and the currents
at that depth, the model determines the trajectories of the larvae through the
ocean. Larvae may be swept out to sea, where they would perish, or they may
be retained near the coast, where they could settle and mature. The scientists
found that the proportion of larvae retained—and therefore potentially surviving to adulthood—depends on where the larvae were born and the oceanographic conditions during the period that they drift (see figure above).
Off southern and central California, oil
and gas platforms serve as reef-like homes
for large numbers of juvenile rockfishes.
The juveniles settle at the platforms or
at natural reefs after drifting with ocean
currents. Scientists, resource managers,
and conservationists have debated the
ecological consequences for rockfishes if
decommissioned platforms are removed.
Do the platforms help boost rockfish
numbers by providing additional habitat, or
do the platforms simply attract fish that
otherwise would settle at natural reefs? In
collaboration with scientists funded by the
U.S. Minerals Management Service, PISCO/
UCSB scientists developed a model that
offers insights. Using data from high-frequency radar that measures the speed and
direction of ocean currents, the scientists
simulated the likely paths of juvenile rockfishes drifting near a platform located off
Point Conception. The model showed that
most of the juveniles would drift offshore,
away from suitable natural reefs, if there
were no platform at which they could
settle. This result suggests that oil and gas
platforms provide supplemental habitat for
juvenile rockfishes that otherwise would
perish offshore. However, the model does
not yet account for swimming efforts
since little is known about the behavior
of juvenile rockfish in the coastal ocean.
PISCO scientists now seek to incorporate
behavior into the model, enabling more accurate understanding of the role of oil and
gas platforms as rockfish habitat.
Researchers are Brian Emery, Milton Love,
Mary Nishimoto (UCSB), Libe Washburn
(PISCO/UCSB), and Carter Ohlmann (Scripps).
Publication: Do oil and gas platforms off California reduce recruitment of bocaccio (Sebastes
paucispinis) to natural habitat? An analysis based
on trajectories derived from high-frequency radar.
Fisheries Bulletin, in press.
Researchers are Anna Pfeiffer-Hoyt, Margaret McManus (PISCO/UCSC/
University of Hawaii), Pete Raimondi (PISCO/UCSC), and Yi Chao
(Jet Propulsion Laboratory).
Publication: Dispersal of barnacle larvae along the central California coast: A modeling study.
Limnology and Oceanography (in review).
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Young bocaccio rockfish (Sebastes paucispinis).
Photo: Donna Schroeder
Barnacle Life History
Barnacles, mussels, and many other marine
invertebrates begin life as tiny larvae that
are carried by ocean currents, possibly
long distances. After a period of weeks or
months, they attach onto rocks and other
hard surfaces, where they live as adults.
Ecologists often study barnacles as model
species to gain insight into the ecology of
invertebrates with free-swimming larvae.
The illustration above shows generalized
adult and young life stages of barnacles.
The adults release free-swimming young,
ranging in size from 0.25 to 1 millimeter,
into the water. The young, or larvae, molt
several times, developing from the nauplius stage to the cyprid stage. Eventually,
cyprids settle onto hard surfaces, attaching themselves with adhesive and maturing into adults. Ocean currents strongly
affect where and when barnacles settle
and live as adults along the coast. PISCO’s
long-term program of oceanographic and
ecological monitoring is investigating the
complex effects of ocean circulation on
the arrival of young barnacles to replenish
local populations. The research is essential
to understanding fluctuations in abundance
of shellfish and other invertebrates and
will enable better resource management.
The island of Santa Cruz near Santa Barbara, California, lies at the convergence
of two major ocean currents. PISCO/UCSB scientists Carol Blanchette and
Bernardo Broitman used the unique setting to examine how currents affect
the timing and abundance of young invertebrates arriving to inhabit the rocky
shore. For five years, the scientists monitored the population replenishment
of mussels and barnacles at several sites on the island; every two to three
months, they counted the young that had settled onto collectors fastened to
the rocks. Over the same period, the researchers used satellite remote sensing
of seawater temperatures to track ocean currents around the island.
Oceanographic conditions and rates of population replenishment differed
strikingly between the island’s eastern and western sides. Persistently warm
water bathed the eastern shore, where large numbers of young barnacles and
mussels settled. Meanwhile, cold water prevailed at western sites, and few barnacles and mussels settled. Differences also emerged in the settlement patterns
of the two species. Population replenishment of barnacles happened sporadically and tended to be simultaneous around the island. Mussels, in contrast,
settled more continually over time, and sites differed markedly in the number
of young. The findings suggest that the warm currents brought high numbers
of larvae to eastern sites, while cold currents brought few larvae to western
sites, and differences in mussel and barnacle behavior or development apparently caused different patterns of population replenishment. The findings may
have implications for the design and effects of marine protected areas such as
those recently established in the Channel Islands.
oceanographic frontiers
Currents Influence Population Replenishment
Publication: Recruitment of intertidal invertebrates and oceanographic variability at Santa Cruz
Island, California, U.S.A. Limnology and Oceanography 50(5), 2005, 1473–1479.
9
Because of ocean currents, the western shores
of Santa Cruz Island, California, have colder
water (blue colors) than the eastern shores,
which are bathed in warmer waters (yellow-red
colors).
Large numbers of young
barnacles (upper graph)
and mussels (lower
graph) settled along
the island’s eastern
shores (red lines), while
few settled along the
western shores (blue
lines), suggesting that the
warmer current carried
more young to the
island. In addition, mussels settled over a long
period between winter
and summer, whereas
barnacles settled in
pulses during the spring
and summer, indicating
that differences in
biology affected their
settlement patterns.
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Position along coast
Year
Kelp canopy biomass (tons/kilometer of coast)
PISCO scientists at UCSB and UCSC analyzed data from monthly aerial surveys
to produce this figure showing changes in kelp beds in southern California over
34 years. Green indicates abundant kelp. Large kelp beds characterize some
sections along the coast, such as at sites A, B, and C, but the amount of kelp at
any site varied over time. At site C, for example, the strong El Niño in 1997-1998
caused a die-off of kelp. Survey data from ISP Alginates, Inc.
ecological linkages
Long-term Changes in Kelp Forests
A large kelp forest in the Channel Islands is visible from
the air. Photo: Ben Waltenberger
Dispersal of Kelp Spores
To reproduce, kelp release spores that
drift some distance away before settling
onto the sea bottom. Knowing typical
dispersal distances of kelp spores is critical
to understanding regional changes in kelp
forests. PISCO researchers in collaboration with UCSB biologist Dan Reed have
created a mathematical model that incorporates coastal oceanography and spore
biology to mimic spore dispersal. Predictions from the model compared favorably
to real-world measurements of spore
dispersal from an experimental kelp population. The model allows the scientists to
examine the importance of factors such as
wave height, current speed, turbulence, and
height at which the spores are released
above the sea bottom in affecting spore
dispersal patterns. The research shows
that while many kelp spores settle close
to their parent, a sizeable fraction travel
hundreds to several thousands of meters
before settling on the seafloor. While
shorter-distance dispersal is adequate for
the maintenance of extant kelp forests,
longer-distance dispersal is needed for the
recolonization of kelp in forests that have
gone locally extinct.
U
nderwater forests of
giant kelp are extremely important
habitats along the U.S. West Coast,
supporting numerous fish and invertebrate
species. El Niño and storms strongly affect the
locations and sizes of kelp forests by removing kelp
from the sea bottom, which in turn influences the
animals that live there.
To understand how climate change might affect kelp forests, PISCO scientists
collaborated with UCSB researcher Dan Reed on a project funded by the
National Science Foundation to investigate the long-term trends in giant kelp
abundance along 500 kilometers of the southern California coast over 34
years. Together, they combined monitoring data, oceanographic modeling,
and field experiments to estimate extinction and colonization rates of kelp
patches in relation to oceanographic conditions, patch size, and connectivity
with other kelp forests.
Data from monthly aerial surveys showed that patches of giant kelp underwent frequent extinctions and recolonizations over time scales from several
months to over a decade (see figure, opposite page). In most cases, kelp
forests disappeared for less than two years before being recolonized by new
kelp. Small, isolated kelp forests were more likely to go extinct than were large
forests surrounded by other forests. Conversely, recolonization was more likely
for large patches and less likely for isolated patches.
The scientists also studied the dispersal of kelp spores, which enable the kelp
to recolonize the sea bottom (see sidebar). This investigation of kelp forest
dynamics provides new insights into the degree of connectivity among kelp
forests and tools for better predicting effects of changing ocean climate.
Kelp researchers are Dan Reed (UCSB); Brian
Gaylord, Brian Kinlan, and Libe Washburn
(PISCO/UCSB); and Peter Raimondi and
Patrick Drake (PISCO/UCSC). Brian Gaylord is
now an assistant professor at the University of
California, Davis.
Publications: Physical-biological coupling in spore
dispersal of kelp forest macroalgae. Journal of
Marine Systems 49 (2004): 19-39.
Macroalgal spore dispersal in coastal environments: Mechanistic insights revealed by theory and
experiment. Ecological Monographs (in review).
A metapopulation perspective on patch dynamics
and connectivity of giant kelp. In J.P. Kritzer and P.F.
Sale (eds.). Marine Metapopulations. 2006. Academic
Press, San Diego.
Kelp rockfish (Sebastes atrovirens) in a kelp forest (Macrocystis pyrifera). Photo: Luke Miller
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12
From 1999 to 2005, PISCO measured many ecological parameters at multiple sites at each cape indicated on the map. Patterns found in four parameters are illustrated above. Abundance of macrophytes (seaweeds and seagrasses) correlated inversely with invertebrate abundance at many capes. At Cape Foulweather in Oregon, for example, macrophytes were
abundant, and invertebrates were scarce. Concentrations of the important nutrient nitrate were lower in the intermittent upwelling regime than in the persistent upwelling regime, and
phytoplankton were more abundant. Cape Perpetua consistently had low nitrate concentrations and high chlorophyll concentrations.
Regional Oceanography Shapes Ecological Patterns
Ecological Monitoring
Ecological studies of marine systems traditionally focus on local biological interactions such as predation and competition. However, large-scale events like El
Niño or climate change can alter local ecology by affecting supplies of larvae,
nutrients, and phytoplankton. In multi-year studies along 1,300 kilometers of
the coast, PISCO scientists are finding that ecological patterns on the scale of
capes and bays can arise from interactions between regional-scale oceanographic events and local-scale ecological processes.
A major component of PISCO is a coordinated, large-scale program of ecological
and oceanographic monitoring along the
U.S.West Coast.The monitoring program
includes:
In northern California and Oregon, two distinct oceanographic regimes occur.
North of Cape Blanco, Oregon, the strong jet of the California Current flows
parallel and close (20-50 kilometers) to shore, and summertime upwelling of
cold water is sporadic; this regime is called “intermittent upwelling.” South of
Cape Blanco, the jet meanders as far as 300 kilometers offshore, and upwelling is more consistent; this regime is called “persistent upwelling.”
Spanning both regimes, PISCO scientists have measured numerous ecological
parameters. The results show clear patterns, such as relatively high chlorophyll
concentrations and lower nutrient concentrations in the intermittent upwelling regime and inverse relationships between macrophyte and invertebrate
abundance. Researchers are now evaluating the extent to which large-scale
oceanographic conditions determine differences in the patterns and underlying processes in ecological communities, such as population replenishment
rates, organism growth, and species interactions.
PISCO/OSU researchers are Bruce Menge, Francis Chan, Sally Hacker, Maria
Kavanaugh, and Christopher Krenz. Maria Kavanaugh is now a doctoral student at the College of Oceanic and Atmospheric Sciences at OSU. Christopher
Krenz is now a John A. Knauss Marine Policy Fellow in Washington, D.C.
0ARTNERSHIPFOR)NTERDISCIPLINARY3TUDIESOF#OASTAL/CEANS
• measuring population replenishment of
key shoreline invertebrates and reef fish
from spring to late fall,
• biological surveys at approximately 50
rocky reef and kelp forest sites and 100
shoreline sites, and
• monthly coastal transects in Oregon to
monitor conditions at representative sites.
Through these integrated monitoring
efforts, PISCO identifies changes in the
ecosystem and designs experiments to
understand the underlying causes. More
than six years of large-scale monitoring
data from PISCO provides scientists and
resource managers with detailed information on species distributions, population
fluctuations, shifts over time, and oceanographic changes along the coast.
For more information: www.piscoweb.org
Sea urchins develop from fertilized egg to larva in an uncertain world, drifting with the ocean currents. Prevailing oceanographic conditions can expose
these vulnerable life stages to new environmental conditions and transport
them away from their adult habitat. PISCO/UCSB scientists are studying the
effects of temperature changes on the pluteus larvae of four common urchins in the genus Strongylocentrotus. The goal is to understand the role of
water temperature in setting the northern and southern limits of the species’
ranges along the west coast. The scientists have found that differences as
small as one degree can have dramatic effects down to the molecular level.
Interestingly, urchin larvae from colder, northern waters are more sensitive to
changes in temperature than their southern relatives. The geographic range
of northern urchins likely is limited by temperature at its southern end. Knowing how urchin larvae respond to changing temperatures at large geographic
scales may enable predictions about the impacts of both short- and long-term
climate changes on the distribution and abundance of these ecologically and
commercially important species. For example, northern species are likely to be
more susceptible to ocean warming than their southern relatives.
ecological linkages
Effects of Water Temperature on Urchin Survival
PISCO/UCSB researchers are Gretchen Hofmann, LaTisha Hammond, and
Kevin Fielman.
Map (above): White and green sea urchins occur from
southern Puget Sound to Alaska. Purple and red sea
urchins are found from Baja California to Alaska.
Graph (right): Percent mortality of the young (pluteus
larvae) of four urchin species exposed to different temperatures in the laboratory.Young red and purple urchins
tolerated high temperatures better than white and green
urchins, which inhabit colder, northern waters.
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Are Intertidal and Subtidal Species at Equal Risk?
The body temperature of the shoreline-dwelling snail
Tegula funebralis (green line) sometimes went above the
temperature at which its heart function was impaired
(green horizontal line). The body temperature of the
deeper-water snail T. brunnea (blue line) did not cross
the threshold (blue horizontal line). This result indicates
that climate warming threatens T. funebralis more than T.
brunnea. Body temperature fluctuation data from Tomanek
and Somero (1999).
Climate warming is expected to have profound effects on the ocean. Research
by PISCO/Stanford scientists shows that some of the ecological outcomes
may seem paradoxical. The researchers tested the physiological tolerances of
intertidal and subtidal snail species and determined the snails’ capacities for
acclimating to warmer temperatures. A surprising finding was that intertidal
snail species, despite tolerating higher temperatures than their subtidal relatives, face a greater threat from climate warming. Two factors account for this
result. First, the intertidal species currently experience temperatures closer to
their limits of heat tolerance. Second, they have more limited abilities to acclimate to higher temperatures. Consequently, intertidal snails are vulnerable to
the warming climate, while subtidal species have the capacity to tolerate some
warming.
PISCO/Stanford researchers are Emily Stenseng, Caren Braby, and George
Somero. Caren Braby is now a postdoctoral fellow at the Monterey Bay Aquarium Research Institute.
Publication: Evolutionary and acclimation-induced variation in the thermal limits of heart function in
congeneric marine snails: implications for vertical zonation. Biological Bulletin 208 (2005): 138-144.
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Interdisciplinary Courses Train the Next Generation
I
n 2005, PISCO offered two interdisciplinary courses in marine
research and policy as part of its training program for the next generation
of scientists. The participants hailed from the four PISCO campuses—
UCSB, UCSC, Stanford, and OSU—and twelve other institutions.
PISCO’s new Marine Conservation Science and Policy graduate course
was held at Hatfield Marine Science Center in Newport, Oregon. PISCO
scientists Jane Lubchenco and Steve Gaines taught this course with marine
policy experts Andy Rosenberg (University of New Hampshire) and David
Festa (Environmental Defense). PISCO policy coordinators Liz Riley, Satie
Airamé, and Cinamon Vann co-instructed and provided logistical support.
The intensive ten-day course engaged students in hands-on, interactive
learning about the political and legal aspects of marine management, the
role of science in marine policy, and the communication of science to wider
audiences. “There is nothing else like this course in terms of quality and its
unique combination of topics and approach,” said one participant.
In 2005, twenty students attended PISCO’s month-long Biomechanics,
Ecological Physiology, and Genetics of Intertidal Communities course at
Stanford University’s Hopkins Marine Station. PISCO scientists Mark Denny,
Steve Palumbi, and George Somero taught the course. “It was an absolutely
fantastic experience,” said one participant. “I learned some good practical
skills, [and] I’m thinking about ecology in very different ways.”
interdisciplinary
training&research
Does Detritus Determine Differences?
PISCO/UCSC doctoral student Jared Figurski is in-
PISCO/UCSC student Jared Figurski. Photo: Wyatt Patry
vestigating the ecological significance of kelp detritus, a rich mix of decaying
kelp and microorganisms. He has found that reefs along the central coast of
California vary greatly in the quantity of detritus. Because clumps of detritus
are important as food and shelter for fish and other animals, Figurski is testing
the hypothesis that the abundance of detritus leads to ecological differences
among kelp forests. In 2004, his experiments showed that young-of-the-year
rockfish actively seek out patches of kelp detritus as a nursery habitat. In 2005,
he studied the importance of kelp detritus as habitat and food for fish, shrimp,
amphipods, crabs, sea stars, and snails.
Physiology and Ecology of Mussel Reproduction
PISCO/OSU doctoral student Laura Petes is studying
the effects of environmental stressors on the reproduction of mussels on rocky
shores. She found that mussels at the upper edge of the mussel bed, an area
of high heat stress, grow more slowly, allocate less energy towards reproduction, and spawn earlier than do mussels in the lower edge of the mussel bed.
She also has discovered new patterns of pigmentation in mussel reproductive
tissue. Whereas males traditionally have been identified by white reproductive
tissue and females by orange tissue, Petes found that both male and female
mussels in the upper edge of the mussel bed have orange reproductive tissue. The orange color arises from carotenoid pigments, which protect against
damage by oxygen free radicals. Petes is testing whether the high carotenoid
content helps to protect gametes from heat stress.
PISCO/OSU student Laura Petes.
Photo: Jane Lubchenco
Using Genetics to Explore Ecological Linkages
PISCO/UCSB doctoral student Kim Selkoe used genet-
ic techniques to examine possible interdependence of fish populations across
the U.S.-Mexican border. She studied kelp bass (Paralabrax clathratus), which
supports a large recreational fishery in southern California and an artisanal
fishery in Baja California. Many scientists and policy-makers believe that southern California populations of kelp bass are replenished during strong El Niño
years by young fish spawned in Baja and carried north by currents. However,
Selkoe found that kelp bass of southern California have very different genetic
traits and higher genetic diversity than those of Baja. Her findings indicate that
kelp bass populations in California are self-sustaining, not dependent on Baja
populations.
Former PISCO/UCSB doctoral student Kim Selkoe (left)
with fishing assistant Merit McCrea. Photo: Roland Takayama
Kim Selkoe is now a postdoctoral researcher at the Hawaii Institute of
Marine Biology.
Opposite page photos, left to right: Mike Nish,
Jane Lubchenco, Satie Airamé
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interdisciplinary training & research
Student Showcase
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PISCO Teaches Monitoring Methods to
Mexican Fishermen
P
ISCO partnered with the Mexican nonprofit
Comunidad y Biodiversidad (Community and Biodiversity,
or COBI) and a local fishing cooperative in August 2005 to
initiate monitoring of subtidal biological communities in notake marine reserves near Isla Natividad on Mexico’s Pacific
coast. Members of the cooperative decided to close portions of their fishing
area for six years, with a plan to evaluate the effects and possibly increase the
size of the marine reserve system later. Scientists and the fishermen worked
together to identify local species of commercial and ecological importance.
These species will be monitored regularly, both in areas closed to fishing
and those that are fished, to determine the effects of the no-take reserves.
This collaboration represents the first of many under a newly formed
project focusing on small-scale fishing cooperatives in Mexico. PISCO/UCSC
technician Amanda Jensen traveled to Mexico to work with COBI and the
fishermen to modify PISCO’s protocols to enable the local fishermen, often
using hookah diving apparatus, to monitor changes in key species.
sharing
THE
For more information about PISCO’s subtidal monitoring program, including diver
training, visit www.piscoweb.org.
science
The California Resources Agency is working to implement
the Marine Life Protection Act (MLPA) enacted by California in 1999. The
agency selected the central coast from Point Conception to Pigeon Point for
the first phase of a network of marine protected areas (MPAs). PISCO scientists
Steve Gaines, Mark Carr, and Steve Palumbi serve on a Science Advisory Team,
sharing their scientific knowledge through presentations to MLPA decisionmakers and stakeholders on topics from larval dispersal to MPA network design.
The scientists helped to identify species that may benefit from MPAs, and Carr
met regularly with stakeholders from the central coast region. PISCO policy
coordinators Satie Airamé and Cinamon Vann interact closely with state and
federal officials, fishermen, and environmental groups to ensure that PISCO’s
research findings and data are available to answer questions and inform policy.
For more information on the MLPA, go to www.dfg.ca.gov/mrd/mlpa.
sharing the science
PISCO Advises California on Marine Protection Science
Partington Point, near Big Sur, is one area that will be
considered for protection under the MLPA.
Photo: Haven Livingston
Comparing Methods of Stock
Assessment
In 2003 and 2005, PISCO worked with
commercial live-fish fishermen and the
California Department of Fish and Game
to compare two methods of assessing fish
stocks. Accurate information about the
stocks is crucial for setting sustainable
catch limits and evaluating marine protected areas. In Carmel Bay, the scientists
and fishermen compared estimates of
fish abundance from visual surveys by
scuba divers with those estimated from
catch-per-unit-effort (CPUE) by fishing. As
expected, divers counted more fish species
(38) than were caught by fishing gear (20),
and fish abundance and number of species
varied with fishing gear type and method
of deployment. One key result was that
some fish species were sampled better by
fishing (e.g., cabezon, grass rockfish), while
other species were sampled better by divers (e.g., kelp rockfish, kelp greenling). Findings from the 2003 and 2005 studies will
be used to improve fish survey programs
by integrating fishing and diver surveys for
more comprehensive assessments.
Opposite page photos: Matt Robart (left),
Luis Bourillón (right)
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PISCO scientists Steve Gaines and Steve Palumbi work with Monterey Bay National Marine Sanctuary representative
Holly Price during MLPA proceedings. Photo: Satie Airamé
Straight Talks on Fishing
Following on the success of the first series of Straight Talks,
a second series is being organized by PISCO, California Sea Grant, and
representatives of the central California fishing community. The Straight Talk
forums bring together scientists and fishermen to share their knowledge of
the coastal ocean environment and fishing. PISCO/UCSC scientist Mark Carr
and Sea Grant Advisor Rick Starr will lead discussions as they did in the initial
Straight Talks. The forums create an informal, congenial setting where people
can freely discuss topics that often are contentious.
Coastal Management in Oregon
Cape Meares, Oregon. Photo: Matt Robart
PISCO is participating in an initiative to
update Oregon’s Rocky Shore Management
Strategy, which was adopted in 1994 and
provides a framework for coastal management, focusing on 39 rocky shore sites. The
PISCO/OSU policy coordinator sits on the
Technical Advisory Committee that guides
the project, PISCO staff compiled data
sets for decision-makers, and PISCO field
researchers are monitoring human use of
Oregon’s rocky shores.
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Partnership for Interdisciplinary
Studies of Coastal Oceans
(PISCO)
For more information:
Web site: www.piscoweb.org
E-mail: [email protected]
PISCO
Oregon State University
Department of Zoology
3029 Cordley Hall
Corvallis, OR 97331
PISCO
University of California, Santa Cruz
Long Marine Laboratory
100 Shaffer Road
Santa Cruz, CA 95060
PISCO
University of California, Santa Barbara
Marine Science Institute
Santa Barbara, CA 93106-6150
PISCO
Stanford University
Hopkins Marine Station
Oceanview Boulevard
Pacific Grove, CA 93950
Photos, top to bottom and left to right: Roly
Russell, Gretchen Hofmann, Monica Pessino, Jane
Lubchenco, Luke Miller, Sean Hoobler, Monica
Pessino, Jared Figurski, Gil Rilov, Jared Figurski, Cristine
McConnell, Gil Rilov, Tui Anderson, Luke Miller, Cristine
McConnell, Haven Livingston
Paper stock contains 50% recycled content, 15%
post-consumer content. Printed with linseed
oil-based inks.