Density of small corals at two 10m sites on the north shore of Moorea, French Polynesia from 2005 to 2021

Website: https://www.bco-dmo.org/dataset/918330
Data Type: Other Field Results
Version: 1
Version Date: 2024-01-23

Project
» Moorea Coral Reef Long-Term Ecological Research site (MCR LTER)

Program
» Long Term Ecological Research network (LTER)
ContributorsAffiliationRole
Edmunds, Peter J.California State University Northridge (CSUN)Principal Investigator
Burgess, ScottFlorida State University (FSU)Scientist
Maritorena, StephaneUniversity of California-Santa Barbara (UCSB-ERI)Scientist
York, Amber D.Woods Hole Oceanographic Institution (WHOI BCO-DMO)BCO-DMO Data Manager

Abstract
Data Abstract: These data describe the density of small corals (colonies ≤ 4 cm diameter) in quadrats (0.5 x 0.5 m) in size on the benthos at 10 m depth at LTER1 and LTER2 on the north shore of Moorea. Results paper abstract, Edmunds et al. (2024, doi:10.1007/s00442-024-05517-y): * [See "Related Datasets" section for access to related datasets discussed here] Understanding population dynamics is a long-standing objective of ecology, but the need for progress in this area has become urgent. For coral reefs, achieving this objective is impeded by a lack of information on settlement versus post-settlement events in determining recruitment and population size. Declines in coral abundance are often inferred to be associated with reduced densities of recruits, which could arise from mechanisms occurring at larval settlement, or throughout post-settlement stages. This study uses annual measurements from 2008 to 2021 of coral cover, the density of coral settlers (S), the density of small corals (SC), and environmental conditions, to evaluate the roles of settlement versus post-settlement events in determining rates of coral recruitment and changes in coral cover at Moorea, French Polynesia. Coral cover, S, SC, and the SC:S ratio (a proxy for post-settlement success), and environmental conditions, were used in generalized additive models (GAMs) to show that: (a) coral cover was more strongly related to SC and SC:S than S, and (b) SC:S was highest when preceded by cool seawater, low concentrations of Chlorophyll a, and low flow speeds, and S showed evidence of declining with elevated temperature. Together, these results suggest that changes in coral cover in Moorea are more strongly influenced by post-settlement events than settlement. The key to understanding coral community resilience may lie in elucidating the factors attenuating the bottleneck between settlers and small corals.


Coverage

Location: Moorea, French Polynesia
Spatial Extent: N:-17.475083 E:-149.8101 S:-17.4819 W:-149.84833
Temporal Extent: 2005 - 2021

Methods & Sampling

The ecological methods are described in detail in Edmunds et al. (2023), and are briefly summarized below. 

The study utilized the time series of the Moorea Coral Reef LTER, as they relate to coral community dynamics on the north shore fore reef. Annual measurements of coral cover, the density of coral settlers, and the density of small corals were used together with records of the environmental conditions to which they were exposed. Analyses focused on 2008–2021, which captured the final years of the last population outbreak of the crown of thorns (COTs) sea star, the coral population recovery that took place between 2010 and 2019, and coral mortality attributed to bleaching in 2019. Biological data came from two sites (LTER1 and LTER2) that are ~ 3 km apart, with environmental data from the same or similar sites (temperature), one of the two sites (flow at LTER1), or from 4.5 km resolution remote sensing data (Chlorophyll a).

Coral cover was measured annually (April except for 2020 [August] and 2021 [May]) at 10-m depth along a 50 m, permanently marked transect at LTER 1 and LTER 2. Along each transect, 40 photoquadrats (0.5 × 0.5 m) were photographed at positions that were randomly selected in 2005, but fixed thereafter. Pictures were illuminated with strobes, and analyzed using CPCe or CoralNET software with manual annotation of 200 randomly located points on each image. Substrata beneath the points were categorized to coral genus, and the percentage cover for all corals (scleractinians and Millepora) and Pocillopora spp., is reported. The changes in cover of corals (scleractinians and Millepora) provided a holistic summary of the coral community consistent with how we have described it elsewhere and how it is described in the broader scientific literature on coral reefs. The separate summary for Pocillopora spp. provided a measure of coral cover that is the product of the most abundant coral settlers found on tiles deployed in the same habitat (i.e., pocilloporids). The density of small corals (≤ 4-cm diameter) was quantified in the field annually, shortly after the photoquadrats were recorded (but not in 2020 due to COVID-19), and was completed using quadrats (0.5 × 0.5 m) placed in the same positions as the photoquadrats. The benthos, including beneath branching corals, was inspected for small corals that were recorded to genus, and the densities of all corals and Pocillopora spp. are reported in units of corals 0.25 m-2.

* See "Related Datasets" section for access to related dataset pages which include dataset-specific methodology.


BCO-DMO Processing Description

* Sheet "Small corals" of file "Small_Corals.xlsx" was imported into the BCO-DMO data system with values "nd" as missing data values. 
* Sheet "Outer 10 m" of file "Small_Corals.xlsx" was disregarded as directed by the submitter.
** Missing data values are displayed differently based on the file format you download.  They are blank in csv files, "NaN" in MatLab files, etc.
* Column names adjusted to conform to BCO-DMO naming conventions designed to support broad re-use by a variety of research tools and scripting languages. [Only numbers, letters, and underscores.  Can not start with a number]
* dataset references to results publication Edmunds et al 2023 changed to 2024 since that was the year associated with the DOI after final publication. Edmunds et al. (2024, doi:10.1007/s00442-024-05517-y)


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Related Publications

Edmunds, P. J., Maritorena, S., & Burgess, S. C. (2024). Early post-settlement events, rather than settlement, drive recruitment and coral recovery at Moorea, French Polynesia. Oecologia, 204(3), 625–640. https://doi.org/10.1007/s00442-024-05517-y
Results

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Related Datasets

IsRelatedTo
Edmunds, P. J., Burgess, S., Maritorena, S. (2024) Benthic seawater temperature at 10m depth in Moorea, French Polynesia from 2005 to 2021. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2024-01-23 doi:10.26008/1912/bco-dmo.918318.1 [view at BCO-DMO]
Relationship Description: Datasets in support of results publication Edmunds et al. (2023).
Edmunds, P. J., Burgess, S., Maritorena, S. (2024) Density of coral settlers detected on settlement tiles each year at two 10m sites on the north shore of Moorea, French Polynesia from 2008 to 2020. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2024-01-23 doi:10.26008/1912/bco-dmo.918324.1 [view at BCO-DMO]
Relationship Description: Datasets in support of results publication Edmunds et al. (2023).
Edmunds, P. J., Burgess, S., Maritorena, S. (2024) Flow speed on the north shore of Moorea, French from 2007 to 2021. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2024-01-23 doi:10.26008/1912/bco-dmo.918306.1 [view at BCO-DMO]
Relationship Description: Datasets in support of results publication Edmunds et al. (2023).
Edmunds, P. J., Burgess, S., Maritorena, S. (2024) Percentage cover of the benthos by live coral at 10 m depth at sites in Moorea Moorea, French Polynesia from 2008 to 2021. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2024-01-23 doi:10.26008/1912/bco-dmo.918265.1 [view at BCO-DMO]
Relationship Description: Datasets in support of results publication Edmunds et al. (2023).
Edmunds, P. J., Burgess, S., Maritorena, S. (2024) Seawater chlorophyll concentration offshore from Moorea, French Polynesia from 2008 to 2020. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2024-01-23 doi:10.26008/1912/bco-dmo.918299.1 [view at BCO-DMO]
Relationship Description: Datasets in support of results publication Edmunds et al. (2023).
Edmunds, P. J., Burgess, S., Maritorena, S. (2024) Seawater clarity in Moorea, French Polynesia from 2003 to 2022. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2024-01-23 doi:10.26008/1912/bco-dmo.918312.1 [view at BCO-DMO]
Relationship Description: Datasets in support of results publication Edmunds et al. (2023).
Edmunds, P. J., Maritorena, S., Burgess, S. (2024) Density of small corals at two 10m sites on the north shore of Moorea, French Polynesia from 2005 to 2021. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2024-01-23 http://lod.bco-dmo.org/id/dataset/918330 [view at BCO-DMO]
Relationship Description: Datasets in support of results publication Edmunds et al. (2023).
Moorea Coral Reef LTER (n.d.). Moorea Coral Reef LTER: Coral Image Viewer. Accessible from http://mcrlter.msi.ucsb.edu/data/db/census/coralImage.php
IsDerivedFrom
Moorea Coral Reef LTER, & Edmunds, P. (2018). MCR LTER: Coral Reef: Coral Community Dynamics: Coral Recruitment [Data set]. Environmental Data Initiative. https://doi.org/10.6073/PASTA/57B3D0D926DD643B471D261A5984F078 (Accessed 2024-02-21). https://doi.org/10.6073/pasta/57b3d0d926dd643b471d261a5984f078

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Parameters

ParameterDescriptionUnits
Year

Year of survey

unitless
Site

Site of survey (either LTER1 or LTER2)

unitless
Quadrat

Quadrat number at each site

unitless
Pocillopora

Number of Pocillopora spp. colonies

per colony
All_corals

Number of colonies of all corals

per colony


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Instruments

Dataset-specific Instrument Name
Generic Instrument Name
Underwater Camera
Generic Instrument Description
All types of photographic equipment that may be deployed underwater including stills, video, film and digital systems.


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Project Information

Moorea Coral Reef Long-Term Ecological Research site (MCR LTER)


Coverage: Island of Moorea, French Polynesia


From http://www.lternet.edu/sites/mcr/ and http://mcr.lternet.edu/:
The Moorea Coral Reef LTER site encompasses the coral reef complex that surrounds the island of Moorea, French Polynesia (17°30'S, 149°50'W). Moorea is a small, triangular volcanic island 20 km west of Tahiti in the Society Islands of French Polynesia. An offshore barrier reef forms a system of shallow (mean depth ~ 5-7 m), narrow (~0.8-1.5 km wide) lagoons around the 60 km perimeter of Moorea. All major coral reef types (e.g., fringing reef, lagoon patch reefs, back reef, barrier reef and fore reef) are present and accessible by small boat.

The MCR LTER was established in 2004 by the US National Science Foundation (NSF) and is a partnership between the University of California Santa Barbara and California State University, Northridge. MCR researchers include marine scientists from the UC Santa Barbara, CSU Northridge, UC Davis, UC Santa Cruz, UC San Diego, CSU San Marcos, Duke University and the University of Hawaii. Field operations are conducted from the UC Berkeley Richard B. Gump South Pacific Research Station on the island of Moorea, French Polynesia.

MCR LTER Data: The Moorea Coral Reef (MCR) LTER data are managed by and available directly from the MCR project data site URL shown above.  The datasets listed below were collected at or near the MCR LTER sampling locations, and funded by NSF OCE as ancillary projects related to the MCR LTER core research themes.

This project is supported by continuing grants with slight name variations:

  • LTER: Long-Term Dynamics of a Coral Reef Ecosystem
  • LTER: MCR II - Long-Term Dynamics of a Coral Reef Ecosystem
  • LTER: MCR IIB: Long-Term Dynamics of a Coral Reef Ecosystem
  • LTER: MCR III: Long-Term Dynamics of a Coral Reef Ecosystem
  • LTER: MCR IV: Long-Term Dynamics of a Coral Reef Ecosystem


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Program Information

Long Term Ecological Research network (LTER)


Coverage: United States


adapted from http://www.lternet.edu/

The National Science Foundation established the LTER program in 1980 to support research on long-term ecological phenomena in the United States. The Long Term Ecological Research (LTER) Network is a collaborative effort involving more than 1800 scientists and students investigating ecological processes over long temporal and broad spatial scales. The LTER Network promotes synthesis and comparative research across sites and ecosystems and among other related national and international research programs. The LTER research sites represent diverse ecosystems with emphasis on different research themes, and cross-site communication, network publications, and research-planning activities are coordinated through the LTER Network Office.

LTER site location map

2017 LTER research site map obtained from https://lternet.edu/site/lter-network/



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Funding

Funding SourceAward
NSF Division of Ocean Sciences (NSF OCE)

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