http://lod.bco-dmo.org/id/dataset/990975
eng; USA
utf8
dataset
Highest level of data collection, from a common set of sensors or instrumentation, usually within the same research project
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
pointOfContact
2026-01-05
ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data
ISO 19115-2:2009(E)
Sea star size structure from surveys along the Oregon and Northern California rocky intertidal coastline from 2000 to 2024
2026-05-15
publication
2026-05-15
revision
Woods Hole Oceanographic Institution (WHOI BCO-DMO)
2026-05-15
publication
https://doi.org/10.26008/1912/bco-dmo.990975.1
Bruce A. Menge
Oregon State University
principalInvestigator
Sarah Gravem
Oregon State University
principalInvestigator
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
publisher
Cite this dataset as: Gravem, S., Menge, B. A. (2026) Sea star size structure from surveys along the Oregon and Northern California rocky intertidal coastline from 2000 to 2024. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2026-05-15 [if applicable, indicate subset used]. doi:10.26008/1912/bco-dmo.990975.1 [access date]
Dataset Description: <p>This time series was funded in conjunction with the Long Term Research in Environmental Biology [LTREB] program awards (Award DEB-1050694,DEB-1554702,DEB-2050017).<br />
<br />
<span style="font-size:13px">SSWD =&nbsp;Sea star wasting disease</span></p>
<div><span style="font-size:13px">Organism identifiers (Life Science Identifiers, LSIDs):</span></div>
<div><span style="font-size:13px">Pisaster ochraceus, urn:lsid:marinespecies.org:taxname:240755</span></div>
<div><span style="font-size:13px">Pisaster, urn:lsid:marinespecies.org:taxname:240754</span></div> Methods and Sampling: <p><span style="font-size:13px">Our studies took place at eight sites along the Oregon coast spanning ~260 km from 44.5N to 42.75N latitude (Fig. 1, Table S1 of Gravem and Menge (2025)).&nbsp;</span> All are predominantly rocky shores with relatively gentle slopes and have typical patterns of zonation, with a high-intertidal zone dominated by barnacles and fucoid algae, a mid-intertidal zone dominated by mussels, and a low-intertidal zone with a diverse assemblage of macrophytes and sessile invertebrates.</p>
<p>Belt Transects</p>
<p>Because of the importance of <em>Pisaster </em>in influencing community structure through its consumption of mussels and other prey, in 2000-2001 we initiated a program of ~twice-annual belt transects to quantify sea star size structure and density at each site. Surveys generally occurred in spring (April or May) and summer (July, August, or September), but in some years surveys were more or less frequent. Belt transects were replicated (n = 5) in 2 x 5 or 2 x 10 m rectangular areas (plots or belts) sampled below the bottom edge of mussel beds in the same location each year, with plot size enlarged to 2 x10m at years or sites when <em>Pisaster </em>abundance was low. Belt replicates were spaced throughout the defined study site to capture the density of <em>Pisaster</em> just below mussel beds. In each belt, researchers carefully searched for and collected all sea stars present and then wet weighed and measured arm lengths (madreporite to tip of opposite arm). Sea stars were often abundant, so when we reached the threshold of 200 animals in site and sample date, we finished that transect, then discontinued weighing and measuring in subsequent transects. Instead, we counted the remaining sea stars in these transects to capture densities. When sea stars were sparse, we surveyed additional transects (up to 10 total) to assess size structure of 200 animals where possible, but these additional transects were not used for density calculations since they were not replicated over time. After measurements, all sea stars were returned to their respective belt plots. Overall, we performed 440 surveys over 24 years at these 8 sites, which included 1,582 transects and measurements of 143,241 individual sea stars.</p>
<p>&nbsp;</p>
<p>We calculated density as the count in each plot divided by plot area, which we calculated separately for each life stage for measured animals (see below). We calculated average size in each transect as the average wet weight. Since time constraints, the SSWD pandemic, or field scale failure sometimes forced us to measure only arm lengths but not weights, we developed an equation for estimating weights based on lengths as [wet weight in grams = 0.417 * (arm length in cm)<sup>2.574</sup>]. We calculated biomass density as the total weight of animals per meter<sup>2</sup> in each transect. This is a potentially more accurate measure of ecological importance since <em>Pisaster</em> can vary several orders of magnitude in size and since potential predation rates and top-down control of mussels can increase dramatically as sea stars grow.</p>
<p>Sea Star Wasting Surveys and Disease Phases</p>
<p>In 2014-2015, when the pandemic was at outbreak levels in Oregon, we quantified disease occurrence using frequent (biweekly to monthly) surveys at each site. For disease frequency surveys, we searched a large area (100s of m<sup>2</sup>) within the study site for all sea stars. We recorded if the animal was apparently healthy or not, and if not, recorded the symptom(s), including lesions, deflation, arm loss, arm twisting, losing grip and disintegration. We calculated percent diseased as the percent of the total animals that exhibited any SSWD symptom. After 2015, disease occurrence mostly was quantified in the belt transects supplemented by periodic wider surveys as above. Since we had never observed a prior outbreak of SSWD nor instances of disease symptoms, we assumed pre-SSWD percent diseased was 0.</p>
<p>Using our disease frequency and demographic data, we divided the SSWD outbreak into 4 phases, with <em>Pre-SSWD </em>(or P<em>re-wasting</em>)<em> </em>as before 2014, <em>During outbreak </em>as 2014 when symptoms peaked, <em>Post-SSWD</em> (or <em>Post-wasting</em>)<em> </em>as 2015-2020 when small outbreaks continued to occur and adult populations were clearly still low, and <em>Current</em> as 2021-2024 when adult populations had begun to recover at several sites (though small outbreaks continued to occur).&nbsp;</p>
<p>&nbsp;</p>
<p>Categorization of Life Stages</p>
<p>We categorized different life stages of <em>Pisaster </em>into recruits (which we sometimes split into young-of-year recruits and older recruits),<em> </em>juveniles, and adults. Post-larval individuals (several weeks or months old) were not targeted by our surveys. We defined ‘young-of-year (YOY) recruits’ ranging in size from 0.01 to 1 g wet weight and 3 to 14 mm arm length . &nbsp;We define older recruits as individuals of 1 to 5 g wet weight, ~1.4 to 2.6 cm in arm length, and based on our size structure histograms are ~2-3 years old. We defined juveniles as individuals 5 to 80 g and ~2.6 to 7.7 cm arm length (this corresponds to roughly 2-6 years old) and defined adults as &gt;80g, and &gt;7.7cm arm length.<br />
<br />
Disease Codes:</p>
<div><span style="font-size:13px">H=Healthy (0)</span></div>
<div><span style="font-size:13px">DF=Deflated (1)</span></div>
<div><span style="font-size:13px">TA=Twisted Arms (2)</span></div>
<div><span style="font-size:13px">L=Lesions (3)</span></div>
<div><span style="font-size:13px">AL=Arm Lost (4)</span></div>
<div><span style="font-size:13px">LG=Losing Grip (5)</span></div>
<div><span style="font-size:13px">D=Dead or Dissolved (6)</span></div>
<div><span style="font-size:13px">AR=Arms Regenerating</span></div>
<div><span style="font-size:13px">PL=Pre/Post Lesion (antiquated)</span></div>
<div><span style="font-size:13px">AH=Assumed Healthy (pre-2013)</span></div>
<div><span style="font-size:13px">PD=Potentially Diseased (pre-2013)</span></div>
<div><span style="font-size:13px">PR=Potentially Recovering (pre-2013)</span></div>
<div><span style="font-size:13px">NONE=None (no data or not applicable)</span></div>
<div><span style="font-size:13px">AD=Arms Damaged</span></div>
Funding provided by NSF Division of Ocean Sciences (NSF OCE) Award Number: OCE-1061233 Award URL: https://www.nsf.gov/awardsearch/show-award?AWD_ID=1061233
Funding provided by NSF Division of Ocean Sciences (NSF OCE) Award Number: OCE-1061530 Award URL: https://www.nsf.gov/awardsearch/show-award?AWD_ID=1061530
Funding provided by NSF Division of Ocean Sciences (NSF OCE) Award Number: OCE-0726983 Award URL: https://www.nsf.gov/awardsearch/show-award?AWD_ID=0726983
Funding provided by NSF Division of Ocean Sciences (NSF OCE) Award Number: OCE-1448913 Award URL: https://www.nsf.gov/awardsearch/show-award?AWD_ID=1448913
Funding provided by NSF Division of Ocean Sciences (NSF OCE) Award Number: OCE-1735743 Award URL: https://www.nsf.gov/awardsearch/show-award?AWD_ID=1735743
Funding provided by NSF Division of Ocean Sciences (NSF OCE) Award Number: OCE-1735911 Award URL: https://www.nsf.gov/awardsearch/show-award?AWD_ID=1735911
Funding provided by NSF Division of Environmental Biology (NSF DEB) Award Number: DEB-2050017 Award URL: https://www.nsf.gov/awardsearch/show-award?AWD_ID=2050017
Funding provided by NSF Division of Environmental Biology (NSF DEB) Award Number: DEB-1554702 Award URL: https://www.nsf.gov/awardsearch/show-award/?AWD_ID=1554702
Funding provided by NSF Division of Environmental Biology (NSF DEB) Award Number: DEB-1050694 Award URL: https://www.nsf.gov/awardsearch/show-award/?AWD_ID=1050694
completed
Bruce A. Menge
Oregon State University
541-737-5358
Department of Integrative Biology 4575 SW Research Way
Corvallis
OR
97333
USA
mengeb@oregonstate.edu
pointOfContact
Sarah Gravem
Oregon State University
sgravem@calpoly.edu
pointOfContact
asNeeded
Dataset Version: 1
Unknown
StarID
TransectDateID
TransectSurveyID
SurveyID
TransectID
GroupCode
Region
Cape
CapeNum
SiteCode_STARS
Site
SiteNum
Latitude
Longitude
SiteType
Year
Month
Day
Date
AvgSurveyDate
SurveyPeriod
Season
SeasonCode
YearOfSSWS
DateofSSWS
YrSinceSSWS
DiseasePhase3
DiseasePhase4
Transect
TransectArea_m2
SpeciesCode
N_Individuals
SeaStarNum
Stage_Field
LengthMethod
WeightMethod
MeasuredArmLength_cm
MeasuredWetWt_g
ArmLength_cm
WetWt_g
Stage_Arm
Stage_Wt
Stage4_Wt
Diet1
Diet2
Diet3
Diet4
Diet5
DetailDisease
DiseaseCode
DiseaseSimple
Surveyors
Notes
EnteredBy
theme
None, User defined
sample identification
transect
sample description
transect_code
region
site description
Site_ID
site
latitude
longitude
year
month of year
day of month
date
No BCO-DMO term
season
time_elapsed
area_measured
taxon_code
count
individual
sampling_method
length
weight
wet_weight_biomass
person name
comments
featureType
BCO-DMO Standard Parameters
otherRestrictions
otherRestrictions
Access Constraints: none. Use Constraints: Please follow guidelines at: http://www.bco-dmo.org/terms-use Distribution liability: Under no circumstances shall BCO-DMO be liable for any direct, incidental, special, consequential, indirect, or punitive damages that result from the use of, or the inability to use, the materials in this data submission. If you are dissatisfied with any materials in this data submission your sole and exclusive remedy is to discontinue use.
Partnership for Interdisciplinary Studies of Coastal Oceans
http://www.piscoweb.org/
Partnership for Interdisciplinary Studies of Coastal Oceans
The Partnership for Interdisciplinary Studies of Coastal Oceans is a long-term ecosystem research and monitoring program established with the goals of:
understanding dynamics of the coastal ocean ecosystem along the U.S. west coast
sharing that knowledge so ocean managers and policy makers can make science based decisions regarding coastal and marine stewardship
producing a new generation of scientists trained in interdisciplinary collaborative approaches
Over the last 10 years, PISCO has successfully built a unique research program that combines complementary disciplines to answer critical environmental questions and inform management and policy. Activities are conducted at the latitudinal scale of the California Current Large Marine Ecosystem along the west coast of North America, but anchored around the dynamics of coastal, hardbottom habitats and the oceanography of the nearshore ocean – among the most productive and diverse components of this ecosystem. The program integrates studies of changes in the ocean environment through ecological monitoring and experiments. Scientists examine the causes and consequences of ecosystem changes over spatial scales that are the most relevant to marine species and management, but largely unstudied elsewhere.
Findings are linked to solutions through a growing portfolio of tools for policy and management decisions. The time from scientific discovery to policy change is greatly reduced by coordinated, efficient links between scientists and key decision makers.
Core elements of PISCO are:
Interdisciplinary ecosystem science
Data archiving and sharing
Outreach to public and decision-making user groups
Interdisciplinary training
Coordination of distributed research team
Established in 1999 with funding from The David and Lucile Packard Foundation, PISCO is led by scientists from core campuses Oregon State University (OSU); Stanford University’s Hopkins Marine Station; University of California, Santa Cruz (UCSC); and University of California, Santa Barbara (UCSB). Collaborators from other institutions also contribute to leadership and development of PISCO programs. 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. Core support, along with additional funding from diverse public and private sources, make this unique partnership possible.
PISCO
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program
Long Term Research in Environmental Biology
https://www.nsf.gov/funding/opportunities/ltreb-long-term-research-environmental-biology
Long Term Research in Environmental Biology
Long Term Research in Environmental Biology (LTREB)
Supports research for a period of 10 years or longer to generate an extended time series of data with a focus on evolutionary biology, ecology and ecosystem science.
Synopsis
The Long Term Research in Environmental Biology (LTREB) Program supports the generation of extended time series of data to address important questions in evolutionary biology, ecology, and ecosystem science. Research areas include, but are not limited to, the effects of natural selection or other evolutionary processes on populations, communities, or ecosystems; the effects of interspecific interactions that vary over time and space; population or community dynamics for organisms that have extended life spans and long turnover times; feedbacks between ecological and evolutionary processes; pools of materials such as nutrients in soils that turn over at intermediate to longer time scales; and external forcing functions such as climatic cycles that operate over long return intervals.
LTREB
largerWorkCitation
program
Collaborative Research: The role of calcifying algae as a determinant of rocky intertidal macrophyte community structure at a meta-ecosystem scale
https://osprey.bco-dmo.org/project/2199
Collaborative Research: The role of calcifying algae as a determinant of rocky intertidal macrophyte community structure at a meta-ecosystem scale
<p><strong>Algal Communities in Distress: Impacts and Consequences (ACIDIC)</strong></p>
<p>Environmental stress models have recently been modified to incorporate the influence of facilitation to join negative effects such as predation, competition, and abiotic stress as determinants of community structure. Nevertheless, our empirical understanding of the processes that regulate the expression of facilitation effects across systems and the potential for facilitation to amplify or dampen the ecological consequences of climate change remains limited. This project focuses on facilitation dynamics in the broader meta-ecosystem concept, which hypothesizes that variation among communities depends not only on locally-varying species interactions and impacts of abiotic factors such as environmental stress and physical disturbance but also on regionally- and globally-varying ecosystem processes such as dispersal and flows of materials such as nutrients and carbon. The investigators will study the influence of a potentially critical facilitative interaction between coralline algal turfs and canopy-forming macrophytes including kelps and surfgrass in a rocky intertidal meta-ecosystem. The research will be conducted in a climate change context, with a focus on how the macrophyte-coralline interaction is influenced by ocean conditions, including factors driven by variable upwelling (temperature, nutrients, phytoplankton abundance, and light) and increases in ocean acidification, which vary in a mosaic pattern along the coast of the northern California Current (NCC) in Oregon and northern California.</p>
<p>The goal of the project is to test the hypothesis that the coralline turf-macrophyte canopy interaction is a cardinal interaction in the determination of low rocky intertidal community structure, and that disruption of this interaction would dramatically alter the structure and function of this kelp- and surfgrass-dominated assemblage. The project will take advantage of, and enhance, a research platform established across 17 sites spanning ~800 km in the NCC coastal meta-ecosystem with prior NSF funding that will at each site: (1) quantify ocean conditions, including temperature, nutrients, phytoplankton, light (PAR), and carbonate chemistry to document the response of community structure oceanographic variation across a meta ecosystem mosaic; (2) carry out field experiments testing the nature of the interaction between coralline algal turfs (primarily Corallina vancouveriensis) and dominant canopy species, the kelp Saccharina sessile and the surfgrass Phyllospadix scouleri; and (3) carry out laboratory experiments focusing on the mechanism of the interaction, specifically testing the effects of carbonate chemistry, light, temperature, and nutrients. Component (1) will employ both remote sensors deployed in the intertidal (fluorometers, thermal sensors, PAR sensors, and a recently developed pH sensor) and direct sampling (nutrients, phytoplankton, pCO2, and pH) to quantify the in situ exposure regime of benthic primary producers to resources, energy, and environmental stress across spatial scales. These metrics will be combined with a newly developed index for quantifying local-scale variation in upwelling intensity to characterize the linkages between climate forcing and ecosystem state. Coupling oceanography with our field and laboratory experiments will provide unique and valuable insights into how the current state of rocky intertidal ecosystems is likely to be altered in the future.</p>
<p>Intellectual Merit. The project will contribute one of the first studies to test the community consequences of varying upwelling and CO2 across an ecosystem scale. How these factors alter the direct and indirect interactions of key species is of fundamental importance in our efforts to learn how field ecosystems will respond to climate change. Such knowledge is crucial to our efforts to manage and conserve marine communities facing human-induced variation in climate.</p>
ACIDIC
largerWorkCitation
project
Collaborative Research: Scaling up from community to meta-ecosystem dynamics in the rocky intertidal - a comparative-experimental approach
https://osprey.bco-dmo.org/project/2206
Collaborative Research: Scaling up from community to meta-ecosystem dynamics in the rocky intertidal - a comparative-experimental approach
<p><strong>Collaborative Research: Scaling up from community to meta-ecosystem dynamics in the rocky intertidal - a comparative-experimental approach</strong></p>
<p>The meta-ecosystem concept hypothesizes that the dynamics of ecological communities reflect interdependence between local-scale and ecosystem processes that vary across large distances. Thus, variation among communities depends not only on locally-varying species interactions and abiotic factors, such as physical disturbance, but also on regionally- and globally-varying ecosystem processes, such as dispersal and flows of materials such as nutrients and carbon. This study of rocky intertidal communities and the factors underlying their variation addresses the issue of meta-ecosystem dynamics. The goal of this project is to understand how variability in oceanographic subsidies, such as nutrients and phytoplankton, influences benthic community structure in the northern California Current Large Marine Ecosystem. Local-scale variation in upwelling along the Oregon and northern California coasts will be used to understand how changes in nutrients and productivity influence benthic-pelagic coupling, its effect on benthic species interactions, and ultimately rocky intertidal community structure. A conceptual model, in which the independent variable is seawater temperature (SWT), is used to predict how the dual effect of nutrients and light on marine benthic and pelagic primary production generates different community outcomes in the low intertidal zone. The two "endpoints" of community structure are a dominance of filter feeding invertebrates or macroalgae. The model predicts that with low (cold) SWT, nutrient and light availability is high, and macrophytes are dominant. Under very high nutrients and light, competitively dominant kelps will prevail and possibly facilitate stress-intolerant macroalgal species, and as nutrients and light diminish, kelp dominance should switch to dominance by surfgrass and foliose understory algae. With higher (warmer) SWT, conditions favor high phytoplankton production, leading to dominance by sessile invertebrates. High phytoplankton also creates low light and low nutrient conditions, negatively affecting growth of macroalgae and their ability to compete with sessile invertebrates. Research will be conducted at 15 sites nested within five capes spanning the 1300 km range of the study region. A water sampling program will quantify concentrations of nutrients and phytoplankton, field-deployed remote sensors will provide time-series estimates of light and chlorophyll a, and surveys will quantify community structure. Manipulative field experiments will test the role of species interactions on community structure and how interactions vary with ecological subsidies.</p>
Meta-Eco
largerWorkCitation
project
RAPID: Testing the rocky intertidal community consequences of the decimation of purple sea star populations along the Oregon coast by sea star wasting disease
http://www.eeb.ucsc.edu/pacificrockyintertidal/data-products/sea-star-wasting/
RAPID: Testing the rocky intertidal community consequences of the decimation of purple sea star populations along the Oregon coast by sea star wasting disease
<p>This study will investigate the ecological consequences of the decimation of sea star populations by wasting disease along the Oregon coast. Hallmarks of wasting disease are the formation of sores on the sea star that progress to cause loss of arms, and ultimately death of the animal. Wasting disease was reported in sea star populations including those of the purple sea star, Pisaster ochraceus, in British Columbia, Washington, and California as early as April 2013. In Oregon, wasting was first observed in April 2014, and by June 2014 rates of infection ranged up to 80%, and sea star abundance had declined. At that rate, many populations may disappear by the end of summer 2014. Prior research has shown that in the absence of the purple sea star, mid-shore mussel populations increase, and ultimately overgrow the sea weeds and invertebrates that occur low on the shore, reducing biodiversity. However, because disease events of this magnitude have never occurred along the entire coastline, it is unclear if the small-scale expansion of mussels observed previously will be a general result of this event. One possibility is that predators unaffected by wasting, such as whelks and crabs, will increase their predation effects and blunt the expected invasion of mussels to the low shore. The research in this project will evaluate this possibility by testing the role of these alternative predators. Broader Impacts include the training of undergraduate and graduate students, the involvement of coastal residents and the production of microdocumentaries and video to document the changing context of this ecosystem.</p>
<p>The research project is designed to test three hypotheses. First, that in the absence of Pisaster ochraceus, predation by whelks will increase in strength through increases in whelk abundance and in whelk size, and at least partially compensate for the absence of Pisaster. Second, the small sea star Leptasterias spp. will also expand its role as a predator through increased size and abundance, and expansion of its habitat beyond mussel beds. Although individuals of this sea star have been observed to suffer from wasting as well, the frequency so far appears low, and it seems likely this species may persist. Third, the crab Cancer productus, normally mostly a subtidal species, will expand its range into the intertidal and help to compensate for the loss of Pisaster. Tests of these hypotheses will include manual removal experiments (whelk removal, Leptasterias removal, removal of both and of neither), cage exclusion experiments (whelk exclusions), cage inclusion-exclusion experiments (Leptasterias inclusion, Leptasterias exclusion). Experiments will be replicated with appropriate controls, and done at multiple sites on the central Oregon coast that vary naturally in population abundances, rates of prey and predator recruitment, and oceanographic conditions. Results obtained under this unprecedented set of circumstances will deepen and expand our empirical understanding of the dynamics of an iconic ecosystem, and will help parameterize community models.</p>
<p><strong>Additional Project Information: </strong><a href="http://data.piscoweb.org/marine1/seastardisease.html" target="_blank">Sea Star Wasting Map</a></p>
Sea star wasting
largerWorkCitation
project
LTREB: Testing tipping points in a model rocky intertidal meta-ecosystem – Climate-change, increasing variances, and response mechanisms
https://osprey.bco-dmo.org/project/865695
LTREB: Testing tipping points in a model rocky intertidal meta-ecosystem – Climate-change, increasing variances, and response mechanisms
<p>NSF abstract:</p>
<p>In recent decades, ocean ecosystems, long thought to be immune to change, have undergone disruptions to their structure, diversity, and geographic range, yet the actual underlying reasons for such changes in oceanic biota are often unclear. Coastal intertidal zones (i.e., the shore between high and low tides) have long served as important ecological model systems because of advantages in accessibility and ease of observation, occupancy by easily studied and manipulated organisms of relatively short lifespans, and exposure to often severe environmental conditions. This research will address the stability of a well-known rocky shore system along the Oregon and California coasts. Prior long-term research indicates that, although casual observation suggests these systems are stable, in fact, they may be on the cusp of shifting into another state, losing iconic organisms like mussels and sea stars, and becoming dominated by seaweeds. These changes might be comparable to losing trees and large predators from terrestrial systems. This study would result in the training of undergraduates and graduate students, including individuals from under-represented groups. Additionally, this study would include outreach to the general public.</p>
<p>The researchers will focus particularly on impacts of increasing and more variable warming on community recovery. For example, climate oscillations (e.g., El Niño), coastal upwelling, and particularly temperature have all changed in recent decades in ways leading to increased stress on intertidal biota. In apparent response, coastal ecosystems evidently have become less productive, organismal performance (growth, reproduction) has declined, and key dynamical processes (species interactions) have weakened. The new research will pursue these strong hints of an impending “tipping point” by (1) continuing the projects that led to the insights of increasing instability, (2) adding new projects that will pinpoint ecological changes, and (3) expanding the region of work to include locations in California. Research will assess whether or not sea stars recover from wasting disease, experimentally test if species interactions are indeed weakening, quantify the annual inputs of new prey and changes in abundance, diversity, stability, and resilience of intertidal communities, and document changes in the physical environment. Using field observations and experiments, the research will provide insight into impacts of environmental change, particularly warming, on the future of coastal ecosystems, and more generally, into possible future states of Earth’s ecosystems. Using these data, we will test the hypothesis that direct and indirect effects of climate change are driving, or may drive these systems into new, alternative states.</p>
<p>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.</p>
LTREB Intertidal Tipping Points
largerWorkCitation
project
eng; USA
oceans
-124.56512
-117.79941
33.54476929
45.02574539
2000-07-05
2024-09-19
From projects that focused on the following 3 locations: 1. US West Coast; North bounding latitude: 45.00N, South bounding latitude: 38.00N 2. Oregon coast 3. West coast of North America
0
BCO-DMO catalogue of parameters from Sea star size structure from surveys along the Oregon and Northern California rocky intertidal coastline from 2000 to 2024
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
pointOfContact
http://lod.bco-dmo.org/id/dataset-parameter/998485.rdf
Name: StarID
Units: unitless
Description: <p>Unique identifier for each seastar listing Site_Transect_Date_SpeciesCode_SeaStarNum. [CreatedDuring: DataAnnotation],[CreationDescription: 'Made during BTDataAnnotation'],[Example: FC_BT2_2021-05-13_PISOCH_110]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998486.rdf
Name: TransectDateID
Units: unitless
Description: <p>Unique identifier for each transect listing Site_Transect_Date. [CreatedDuring: DataAnnotation],[CreationDescription: 'Made during BTDataAnnotation'],[Example: FC_BT2_2021-05-13]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998487.rdf
Name: TransectSurveyID
Units: unitless
Description: <p>Unique identifier for each transect listing Site_Transect_Year_SurveySet. [CreatedDuring: DataAnnotation],[CreationDescription: 'Made during BTDataAnnotation'],[Example: FC_BT2_2021_A]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998488.rdf
Name: SurveyID
Units: unitless
Description: <p>Unique identifier for each survey listing Site_Year_SurveySet. [CreatedDuring: DataAnnotation],[CreationDescription: 'Made during BTDataAnnotation'],[Example: FC_2021_A]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998489.rdf
Name: TransectID
Units: unitless
Description: <p>Unique identifier for each transect location, irrespective of date, listing Site_Transect. [CreatedDuring: DataAnnotation],[CreationDescription: 'Made during BTDataAnnotation'],[Example: FC_BT2]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998490.rdf
Name: GroupCode
Units: unitless
Description: <p>Group that took and entered the data. [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet using Validation list'],[CON;LiMPETS;OSU;UCSB;UCSC]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998491.rdf
Name: Region
Units: unitless
Description: <p>Geographic Regions: Oregon, NorCal, CenCal, SoCal. NorCal is PSG and south. CenCal is PPT and south, SoCal is ALEG and south.. [CreatedDuring: DataAnnotation],[CreationDescription: 'Added during BTDataAnnotation using SiteList_STARS'],[Oregon;NorCal;CenCal;SoCal]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998492.rdf
Name: Cape
Units: unitless
Description: <p>Full cape name. Annotated using SiteList_STARS. [CreatedDuring: DataAnnotation],[CreationDescription: 'Added during BTDataAnnotation using SiteList_STARS'],[See sitelist_stars.csv]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998493.rdf
Name: CapeNum
Units: unitless
Description: <p>Cape order from North to South. . [CreatedDuring: DataAnnotation],[CreationDescription: 'Added during BTDataAnnotation using SiteList_STARS'],[See sitelist_stars.csv]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998494.rdf
Name: SiteCode_STARS
Units: unitless
Description: <p>Abbreviation that denotes the site where the data was collected. Site codes are unique to specific locations along the coast. . [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet using Validation list'],[See sitelist_stars.csv or ValidationLists.txt]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998495.rdf
Name: Site
Units: unitless
Description: <p>Full site name. Annotated using SiteList_STARS. [CreatedDuring: DataAnnotation],[CreationDescription: 'Added during BTDataAnnotation using SiteList_STARS'],[See sitelist_stars.csv or ValidationLists.txt]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998496.rdf
Name: SiteNum
Units: unitless
Description: <p>Site order from North to South.. [CreatedDuring: DataAnnotation],[CreationDescription: 'Added during BTDataAnnotation using SiteList_STARS'],[See sitelist_stars.csv]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998497.rdf
Name: Latitude
Units: decimal degrees
Description: <p>Latitude of site.. [CreatedDuring: DataAnnotation],[CreationDescription: 'Added during BTDataAnnotation using SiteList_STARS'],[See sitelist_stars.csv]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998498.rdf
Name: Longitude
Units: decimal degrees
Description: <p>Longitude of site. [CreatedDuring: DataAnnotation],[CreationDescription: 'Added during BTDataAnnotation using SiteList_STARS'],[See sitelist_stars.csv]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998499.rdf
Name: SiteType
Units: unitless
Description: <p>Type of Site for the STARS Project. Core or Ancillary. [CreatedDuring: DataAnnotation],[CreationDescription: 'Added during BTDataAnnotation using SiteList_STARS'],[Core;Ancillary]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998500.rdf
Name: Year
Units: unitless
Description: <p>Year of Survey as a number. [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet'],[Year]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998501.rdf
Name: Month
Units: unitless
Description: <p>Month of Survey as a number. [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet'],[Month]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998502.rdf
Name: Day
Units: unitless
Description: <p>Day of Survey as a number. [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet'],[Day]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998503.rdf
Name: Date
Units: unitless
Description: <p>Date. [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet'],[Date]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998504.rdf
Name: AvgSurveyDate
Units: unitless
Description: <p>The average date of the survey set if survey taken over more than one day, otherwise matches Date [CreatedDuring: DataAnnotation],[CreationDescription: 'Added during BTDataAnnotation'],[Average Date of samples taken for a given survey period and year. ]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998505.rdf
Name: SurveyPeriod
Units: unitless
Description: <p>The survey sets for a given site within a calendar year. Labeled as A, B, C etc. Often are spring and summer surveys labeled A and B, but some years have just one survey (A) and some have 3 (A,B,C) or 4 (A,B,C,D). [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet'],[A, B, C, D]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998506.rdf
Name: Season
Units: unitless
Description: <p>Season of the year according to the month: Months 12-2= WN, 3-5=SP, 6-8=SU, 9-11=FA. [CreatedDuring: DataAnnotation],[CreationDescription: 'Added during BTDataAnnotation'],[SP, SU, FA, WN]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998507.rdf
Name: SeasonCode
Units: unitless
Description: <p>Abbreviation that denotes season as well as year that the data was collected. Is written as abbreviation of season followed by YYYY. . [CreatedDuring: DataAnnotation],[CreationDescription: 'Added during BTDataAnnotation'],[SP2021, FA2018, etc. ]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998508.rdf
Name: YearOfSSWS
Units: unitless
Description: <p>Year SSWS occurred. Usually 2013 in California and 2014 in Oregon. [CreatedDuring: DataEntry],[CreationDescription: 'Added during BTDataAnnotation using SiteList_STARS'],[See sitelist_stars.csv]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998509.rdf
Name: DateofSSWS
Units: unitless
Description: <p>Date SSWS occurred in the region according to Gravem et al. 2020. . [CreatedDuring: DataAnnotation],[CreationDescription: 'Added during BTDataAnnotation using SiteList_STARS'],[See sitelist_stars.csv]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998510.rdf
Name: YrSinceSSWS
Units: years
Description: <p>Years elapsed since SSWS. [CreatedDuring: DataAnnotation],[CreationDescription: 'Calculated During BTDataAnnotation'],[Year- YearOfSSWS in number of years]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998511.rdf
Name: DiseasePhase3
Units: unitless
Description: <p>Disease phase classified as Before, During, or After the DateofSSWS [CreatedDuring: DataAnnotation],[CreationDescription: 'Before (2013 and earlier), During (2014), After (2015 and later)'],[Before, During, After]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998512.rdf
Name: DiseasePhase4
Units: unitless
Description: <p>Disease phase classified as Pre, During, Post, or Current for SSWS [CreatedDuring: DataAnnotation ],[CreationDescription: 'Pre (2013 and earlier), During (2014), Post (2015-2020), Current (2021-2024)'],[Pre, During, Post, Current]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998513.rdf
Name: Transect
Units: unitless
Description: <p>Transect Number with "BT" to indicate Belt Transect. Typically 5 per site. If extra transects of known area were done, they are entered as BT6, BT7, etc. If extra transects were done of unknown area, named BTN and surface area is entered as ND. [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet using Validation list. Fixed transect locations. BTN indicates a star measured but off-transect (so can't be used for density). Only BT1-BT5 are used for density estimates. '],[BT1, BT2…BT8, BTN]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998514.rdf
Name: TransectArea_m2
Units: meters squared (m2)
Description: <p>Area searched in meters squared. Usually 10, indicating 5 x 2 m transect. [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet']</p>
http://lod.bco-dmo.org/id/dataset-parameter/998515.rdf
Name: SpeciesCode
Units: unitless
Description: <p>A 6 digit code for the species. Usually PISOCH or LEPSPP. [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet using Validation list'],[ACASPP;CONCAL;LEPSPP;NONE;NUCCAN;NUCEMA;NUCLAM;NUCLIM;NUCOST;OCESPP;PISOCH]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998516.rdf
Name: N_Individuals
Units: unitless
Description: <p>The number of animals that are described by the row. Enter 1 if animal was measured or weighed. Important: Enter 0 if no animals were found in transect for each species surveyed (e.g. if you have a bunch of PISOCH but no LEP SPP, still enter a row with N_Individuals = 0 for LEPSPP). If the animals were counted by stage or total count and weren't measured/weighed (i.e. LengthMethod = Stage or NA), enter a number to describe total of animals in that species, stage and disease category. . [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet'],[Example 1: counted 14 healthy pisaster and 12 healthy Leptasterias in BT1, sizes unknown. Enter two rows, with N_Indivs = 14 PISOCH and 12 LEPSPP, LengthMethod and Weight Method = NA, DiseaseCode = H. Example 2: counted 3 healthy juvenile pisaster, 1 adult with lesions, and 7 healthy adults. Enter 3 rows for the 3 Juvenile H, 1 Adult L, 7 Adult H. All LengthMethod = Staged]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998517.rdf
Name: SeaStarNum
Units: unitless
Description: <p>Unique seastar number. Restarts every transect and species. [CreatedDuring: DataEntry],[CreationDescription: 'Entered sequentially during Data Entry. Restarts every transect and species'],[This isn't very important, but helps us keep track of individuals. ]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998518.rdf
Name: Stage_Field
Units: unitless
Description: <p>If animals were NOT measured or weighed in the field, but were counted in each stage (Adult, Juv, Recruit), enter the stage here. If so, LengthMethod should also be Staged. Leave blank if arm lengths or weights were measured. [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet IF animals were NOT measured or weighed. Pisaster: Recruit <= 1.5cm arm length, Juvenile >1.5 & < 4, Adult is >= 4. Leptasterias: Recruit <= 0.3cm arm length, Juvenile >0.3 & <1, Adult is >= 1. '],[Recruit, Juvenile, Adult]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998519.rdf
Name: LengthMethod
Units: unitless
Description: <p>What method was used to measure the length of sea stars. For individually-measured stars choose either Madreporite or Center. Typically California is Center and Oregon is Madreporite for Pisaster, and all other sea stars species are Center. Enter Staged for Pisaster or LEPSPP that were split into recruits, juveniles and adults. NA for stars where no size or weight information was included. . [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet. Apex to Notch is for snails (irrelevant here)'],[Madreporite;Center;Staged;Apex to Notch;NA]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998520.rdf
Name: WeightMethod
Units: unitless
Description: <p>What method was used to weigh the sea stars. For individually-weighed stars choose Scale. For stars where weight is estimated from the arm Length_cm, choose Estimated, NA for stars where arm length nor weight information was included. . [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet'],[Scale;Estimate;NA]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998521.rdf
Name: MeasuredArmLength_cm
Units: centimeters (cm)
Description: <p>The arm length in cm measured in the field (enter LengthMethod above). Blank if arm length unmeasured. [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet'],[]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998522.rdf
Name: MeasuredWetWt_g
Units: grams (g)
Description: <p>Weight measured on a scale in the field in grams. Blank if weight unmeasured. [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet'],[]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998523.rdf
Name: ArmLength_cm
Units: centimeters (cm)
Description: <p>Arm length in cm. For PISOCH this is from Madreporite. For all other species this is radius from center. For Pisaster measured from center, see formula following [CreatedDuring: DataAnnotation],[CreationDescription: 'Added during BTDataAnnotation depending on SppCode and LengthMethod'],[If LengthMethod = Center AND SppCode = PISOCH, use formula ( 0.2464+1.076* MeasuredArmLength_cm), otherwise, keep the MeasuredArmLength_cm. ]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998524.rdf
Name: WetWt_g
Units: grams (g)
Description: <p>Weight based on measurement in the field or estimated using arm length and species. See Gravem and Menge 2025 for detailed length to weight analysis and see following formula used for conversions [CreatedDuring: DataAnnotation],[CreationDescription: 'Added during BTDataAnnotation depending on SppCode and LengthMethod'],[If WeightMethod =="Estimate" & SpeciesCode =="PISOCH", then use formula : exp(-0.922196 + 2.5882444 *log(ArmLength_cm)). If WeightMethod =="Estimate" & SpeciesCode =="LEPSPP", use formula exp(-0.763706 + 1.9409451*log(ArmLength_cm)). Otherwise keep MeasuredWetWt_g]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998525.rdf
Name: Stage_Arm
Units: unitless
Description: <p>Stage based on ArmLength_cm or estimated visually from Stage_Field.. [CreatedDuring: DataAnnotation],[CreationDescription: 'Added during BTDataAnnotation depending on SppCode and LengthMethod'],[Filled in using ArmLength cm as follows: Pisaster: Recruit <= 1.5cm arm length, Juvenile >1.5 & < 4, Adult is >= 4. Leptasterias: Recruit <= 0.3cm arm length, Juvenile >0.3 & <1, Adult is >= 1. If no Arm length, keep Stage_Field]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998526.rdf
Name: Stage_Wt
Units: not described
Description: <p>Stage categorized based on the WetWt_g for Pisaster only with 3 categories. Recruit (<5 g wet weight = <2.6 cm arm length) ;Juvenile (5 to 80 g = ~2.6 to 7.7 cm arm length);Adult (>80g = >7.7cm arm length). [CreatedDuring: DataAnnotation],[CreationDescription: 'Added during BTDataAnnotation from WetWt_g'],[Recruit, Juvenile, Adult]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998527.rdf
Name: Stage4_Wt
Units: not described
Description: <p>Stage categorized based on the WetWt_g for Pisaster only with 4 categories. YOY Recruit (0.01 to 1 g = 3 to 14 mm arm length);Recruit (1 to 5 g wet weight = 1.4 to 2.6 cm arm length) Juvenile (5 to 80 g = ~2.6 to 7.7 cm arm length);Adult (>80g = >7.7cm arm length). [CreatedDuring: DataAnnotation],[CreationDescription: 'Added during BTDataAnnotation from WetWt_g'],[YOY Recruit, Recruit, Juvenile, Adult]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998528.rdf
Name: Diet1
Units: unitless
Description: <p>6 digit code for species being eaten. Enter in alphabetical order by genus. [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet'],[See ValidationLists.txt]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998529.rdf
Name: Diet2
Units: unitless
Description: <p>6 digit code for species being eaten. Enter in alphabetical order by genus. [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet'],[See ValidationLists.txt]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998530.rdf
Name: Diet3
Units: unitless
Description: <p>6 digit code for species being eaten. Enter in alphabetical order by genus. [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet'],[See ValidationLists.txt]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998531.rdf
Name: Diet4
Units: unitless
Description: <p>7 digit code for species being eaten. Enter in alphabetical order by genus. [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet'],[See ValidationLists.txt]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998532.rdf
Name: Diet5
Units: unitless
Description: <p>8 digit code for species being eaten. Enter in alphabetical order by genus. [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet'],[See ValidationLists.txt]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998533.rdf
Name: DetailDisease
Units: unitless
Description: <p>Detailed disease notes. [CreatedDuring: DataEntry],[CreationDescription: 'Entered from DataSheet. Freeform entries']</p>
http://lod.bco-dmo.org/id/dataset-parameter/998534.rdf
Name: DiseaseCode
Units: unitless
Description: <p>Most severe disease symptom based on disease notes. See codes for order of severity. H is no symptoms recorded after 2013, AH if no notes before 2013, PD if notes of disease-like symptoms before 2013. [CreatedDuring: DataEntry],[CreationDescription: 'Determined during data entry using data validation. Only one code should be entered (choose most severe)'],[H=Healthy (0);DF=Deflated (1);TA=Twisted Arms (2);L=Lesions (3);AL=Arm Lost (4);LG=Losing Grip (5);D=Dead or Dissolved (6);AR=Arms Regenerating;PL=Pre/Post Lesion (antiquated);AH=Assumed Healthy (pre-2013);PD=Potentially Diseased (pre-2013);PR=Potentially Recovering (pre-2013);NONE=None (no data or not applicable);AD=Arms Damaged ]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998535.rdf
Name: DiseaseSimple
Units: unitless
Description: <p>Simple disease categories : Healthy, Diseased, Recovering. NA if disease not noted. [CreatedDuring: DataAnnotation],[CreationDescription: 'Added during BTDataAnnotation depending on DiseaseCode. '],[Healthy = 'H, AD, AH';Diseased= 'DF, TA, L, AL, LG, D, PD';Recovering = 'AR, PL']</p>
http://lod.bco-dmo.org/id/dataset-parameter/998536.rdf
Name: Surveyors
Units: unitless
Description: <p>Names of people doing survey. [CreatedDuring: DataEntry]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998537.rdf
Name: Notes
Units: unitless
Description: <p>Notes. [CreatedDuring: DataEntry]</p>
http://lod.bco-dmo.org/id/dataset-parameter/998538.rdf
Name: EnteredBy
Units: unitless
Description: <p>Person doing data entry . [CreatedDuring: DataEntry]</p>
GB/NERC/BODC > British Oceanographic Data Centre, Natural Environment Research Council, United Kingdom
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
pointOfContact
https://doi.org/10.26008/1912/bco-dmo.990975.1
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<p><span style="font-size:13px">Our studies took place at eight sites along the Oregon coast spanning ~260 km from 44.5N to 42.75N latitude (Fig. 1, Table S1 of Gravem and Menge (2025)).&nbsp;</span> All are predominantly rocky shores with relatively gentle slopes and have typical patterns of zonation, with a high-intertidal zone dominated by barnacles and fucoid algae, a mid-intertidal zone dominated by mussels, and a low-intertidal zone with a diverse assemblage of macrophytes and sessile invertebrates.</p>
<p>Belt Transects</p>
<p>Because of the importance of <em>Pisaster </em>in influencing community structure through its consumption of mussels and other prey, in 2000-2001 we initiated a program of ~twice-annual belt transects to quantify sea star size structure and density at each site. Surveys generally occurred in spring (April or May) and summer (July, August, or September), but in some years surveys were more or less frequent. Belt transects were replicated (n = 5) in 2 x 5 or 2 x 10 m rectangular areas (plots or belts) sampled below the bottom edge of mussel beds in the same location each year, with plot size enlarged to 2 x10m at years or sites when <em>Pisaster </em>abundance was low. Belt replicates were spaced throughout the defined study site to capture the density of <em>Pisaster</em> just below mussel beds. In each belt, researchers carefully searched for and collected all sea stars present and then wet weighed and measured arm lengths (madreporite to tip of opposite arm). Sea stars were often abundant, so when we reached the threshold of 200 animals in site and sample date, we finished that transect, then discontinued weighing and measuring in subsequent transects. Instead, we counted the remaining sea stars in these transects to capture densities. When sea stars were sparse, we surveyed additional transects (up to 10 total) to assess size structure of 200 animals where possible, but these additional transects were not used for density calculations since they were not replicated over time. After measurements, all sea stars were returned to their respective belt plots. Overall, we performed 440 surveys over 24 years at these 8 sites, which included 1,582 transects and measurements of 143,241 individual sea stars.</p>
<p>&nbsp;</p>
<p>We calculated density as the count in each plot divided by plot area, which we calculated separately for each life stage for measured animals (see below). We calculated average size in each transect as the average wet weight. Since time constraints, the SSWD pandemic, or field scale failure sometimes forced us to measure only arm lengths but not weights, we developed an equation for estimating weights based on lengths as [wet weight in grams = 0.417 * (arm length in cm)<sup>2.574</sup>]. We calculated biomass density as the total weight of animals per meter<sup>2</sup> in each transect. This is a potentially more accurate measure of ecological importance since <em>Pisaster</em> can vary several orders of magnitude in size and since potential predation rates and top-down control of mussels can increase dramatically as sea stars grow.</p>
<p>Sea Star Wasting Surveys and Disease Phases</p>
<p>In 2014-2015, when the pandemic was at outbreak levels in Oregon, we quantified disease occurrence using frequent (biweekly to monthly) surveys at each site. For disease frequency surveys, we searched a large area (100s of m<sup>2</sup>) within the study site for all sea stars. We recorded if the animal was apparently healthy or not, and if not, recorded the symptom(s), including lesions, deflation, arm loss, arm twisting, losing grip and disintegration. We calculated percent diseased as the percent of the total animals that exhibited any SSWD symptom. After 2015, disease occurrence mostly was quantified in the belt transects supplemented by periodic wider surveys as above. Since we had never observed a prior outbreak of SSWD nor instances of disease symptoms, we assumed pre-SSWD percent diseased was 0.</p>
<p>Using our disease frequency and demographic data, we divided the SSWD outbreak into 4 phases, with <em>Pre-SSWD </em>(or P<em>re-wasting</em>)<em> </em>as before 2014, <em>During outbreak </em>as 2014 when symptoms peaked, <em>Post-SSWD</em> (or <em>Post-wasting</em>)<em> </em>as 2015-2020 when small outbreaks continued to occur and adult populations were clearly still low, and <em>Current</em> as 2021-2024 when adult populations had begun to recover at several sites (though small outbreaks continued to occur).&nbsp;</p>
<p>&nbsp;</p>
<p>Categorization of Life Stages</p>
<p>We categorized different life stages of <em>Pisaster </em>into recruits (which we sometimes split into young-of-year recruits and older recruits),<em> </em>juveniles, and adults. Post-larval individuals (several weeks or months old) were not targeted by our surveys. We defined ‘young-of-year (YOY) recruits’ ranging in size from 0.01 to 1 g wet weight and 3 to 14 mm arm length . &nbsp;We define older recruits as individuals of 1 to 5 g wet weight, ~1.4 to 2.6 cm in arm length, and based on our size structure histograms are ~2-3 years old. We defined juveniles as individuals 5 to 80 g and ~2.6 to 7.7 cm arm length (this corresponds to roughly 2-6 years old) and defined adults as &gt;80g, and &gt;7.7cm arm length.<br />
<br />
Disease Codes:</p>
<div><span style="font-size:13px">H=Healthy (0)</span></div>
<div><span style="font-size:13px">DF=Deflated (1)</span></div>
<div><span style="font-size:13px">TA=Twisted Arms (2)</span></div>
<div><span style="font-size:13px">L=Lesions (3)</span></div>
<div><span style="font-size:13px">AL=Arm Lost (4)</span></div>
<div><span style="font-size:13px">LG=Losing Grip (5)</span></div>
<div><span style="font-size:13px">D=Dead or Dissolved (6)</span></div>
<div><span style="font-size:13px">AR=Arms Regenerating</span></div>
<div><span style="font-size:13px">PL=Pre/Post Lesion (antiquated)</span></div>
<div><span style="font-size:13px">AH=Assumed Healthy (pre-2013)</span></div>
<div><span style="font-size:13px">PD=Potentially Diseased (pre-2013)</span></div>
<div><span style="font-size:13px">PR=Potentially Recovering (pre-2013)</span></div>
<div><span style="font-size:13px">NONE=None (no data or not applicable)</span></div>
<div><span style="font-size:13px">AD=Arms Damaged</span></div>
Specified by the Principal Investigator(s)
<p>Descriptions of size and density data processing are described in the associated paper - Gravem and Menge 2025. Metapopulation-scale resilience to disease-induced mass mortality in a keystone predator: From stasis to instability. Ecosphere. 2025;16:e70426. DOI: 10.1002/ecs2.70426</p>
<p>Size data are directly collected in the field by measuring all stars found in belt transects. Density of each transect is calculated from the size data. The number of stars in each transect, species, site and survey are totaled and then divided by the transect size.&nbsp;</p>
Specified by the Principal Investigator(s)
* Sheet BT_Sizes of submitted file "BCODMO_BTMasterAnnot_2000-2024_2025-03-06_SAG.xlsx" was imported into the BCO-DMO data system for this dataset. Values "NA" imported as missing data values. Table will appear as Data File: 990975_v1_belt-transect_sizes.csv (along with other download format options).
Missing Data Identifiers:
* In the BCO-DMO data system missing data identifiers are displayed according to the format of data you access. For example, in csv files it will be blank (null) values. In Matlab .mat files it will be NaN values. When viewing data online at BCO-DMO, the missing value will be shown as blank (null) values.
Supplemental Files:
* Validation Lists extracted from sheet ValidationList in BCODMO_BTMasterAnnot_2000-2024_2025-03-06_SAG.xlsx. Reformatted to not imply this is a table but rather unique lists of controlled vocabulary elements the study used.
* Site list exported from supplied SiteList_STARS.xlsx(version from 2026-05-11) Sheet1 after changing date format to ISO 8601. Attached to dataset as sitelist_stars.csv. Sheet2 contained column information which was added to the sitelist_stars.csv file description after modifications to match the data table (description for column "state" added, column name "LoggerCode_OSU" is "OldLoggerCode_OSU" in data table).
* Parameter (column) information updated from data submitter supplied file BT_Sizes_col-info.xlsx 2026-05-08.
Specified by BCO-DMO Data Managers
asNeeded
7.x-1.1
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
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