Table of Contents

• Coverage
• Dataset Description
  • Methods & Sampling
  • Data Processing Description
  • Problem Description
• Related Datasets
• Parameters
• Instruments
• Project Information
• Funding

See the "Related Datasets" section for other closely related data from the same project/study/experiments. 

Study Description (describes this and related datasets):

Two field experiments and one observational survey were performed investigating how cryptic invertebrate communities (CAFI - Coral Associated Fauna and Invertebrates) interact with and influence coral reef ecosystems in Mo'orea, French Polynesia (2019-2021). The research addresses how spatial configuration of coral habitat affects CAFI community assembly and the reciprocal effects of CAFI on coral health and growth.

Study Experiments and Surveys:
(1) Maatea Size Experiment examining effects of coral colony size on CAFI communities using 60 Pocillopora colonies spanning a natural size gradient.
(2) MRB Amount Experiment testing effects of coral habitat density on CAFI colonization using 54 Pocillopora colonies in low, medium, and high density treatments arranged on a 9x6 experimental grid.
(3) Mo'orea Survey characterizing natural CAFI communities across 114 Pocillopora colonies at multiple reef sites.

Acronyms:

MRB = Maharepa Research Base
CAFI = Coral Associated Fauna and Invertebrates
AFDW = Ash-Free Dry Weight
WoRMS = World Register of Marine Species (marinespecies.org)
AphiaID = Aphia ID (ID for taxonomic names at WoRMS)
LSID = Life Sciences Identifier (ID for taxonomic names - ID includes what database it is for)

​Project location description:

Mo'orea Island, French Polynesia. Data were collected at three primary study sites on backreef habitats at 2-10 meter depth: (1) Maatea site on the south shore east of Atiha Pass (17.60°S, 149.81°W), (2) MRB (Maharepa Research Base) site on the north shore near Maharepa township (17.48°S, 149.81°W), and (3) multiple survey sites distributed around the island including northern and western shores. All sites were located 30-300 meters from the reef crest in sand and coral rubble habitats dominated by Pocillopora corals. Field work was conducted from the UC Berkeley Richard B. Gump South Pacific Research Station.

Study Design:
114 Pocillopora spp. colonies were surveyed across multiple fringing reef sites around Mo'orea during summer 2019 (June-August). Sites were selected to span gradients in wave exposure, depth, and coral density. GPS coordinates were recorded for each colony using handheld Garmin units (+/- 3-5 m accuracy).

Colony Selection:
Colonies were selected haphazardly while snorkeling or SCUBA diving in shallow fringing reef habitats (1-8 m depth). For each colony, the following were recorded in situ: GPS coordinates (decimal degrees), depth (m), colony dimensions (length, width, height), and morphotype.

CAFI Collection:
Colonies were carefully extracted and transported to a field laboratory in sealed containers within 2 hours. Colonies were systematically broken open to expose internal branches and crevices. All visible invertebrates and resident fishes were collected, preserved in 95% ethanol, and identified using stereomicroscopes and taxonomic keys.

Physiological Sampling:
Tissue samples (~5 cm2) were collected from each colony before destructive sampling. A subset (n=21) included paired samples from branch tips and stumps to validate methodological consistency. Samples were frozen at -20C and analyzed for protein (Bradford assay), carbohydrate (anthrone method), and zooxanthellae density (hemocytometer counts).

GPS Coordinate Validation:
GPS coordinates were checked for plausibility (within Mo'orea reef boundaries, appropriate depth). Coordinates are reported as decimal degrees (south latitudes and west longitudes as negative values).

Taxonomic Validation:
All species identifications cross-referenced with WoRMS database. Valid species names, AphiaIDs, and higher taxonomic classifications assigned.

Tip vs. Stump Validation:
For 21 colonies with paired samples, protein, carbohydrate, and zooxanthellae measurements from tips and stumps were compared using paired t-tests. No significant differences were found, validating either tissue type for physiological analyses. Validation data provided as supplemental files.

Quality Control:
Double-entry data digitization. Range checks, cross-file consistency verification, taxonomic nomenclature validation. Missing data represented as blank cells.

Software:
R v4.3+ (tidyverse) for data processing.
GPS validation with QGIS (v3.16+).
Taxonomic validation via WoRMS online taxa match tool.

NSF Award Abstract:
Nearshore habitats such as coral reefs, seagrass beds, and oyster reefs perform a number of services including reducing storm protection, nutrient cycling, and water purification. Many of these habitats have experienced widespread loss and fragmentation due to human activities. This loss threatens the services these ecosystems provide to humans as well as the extraordinary biodiversity of fishes and invertebrates that live within them. However, there is still a lot that is unknown about these habitats which makes it difficult to understand the likely impacts of habitat loss or the benefits of habitat restoration. This research focuses on habitat loss and fragmentation in coral reef ecosystems. The focus of the research is to understand how habitat loss and fragmentation affect the biodiversity of fish and crustaceans on coral reefs in the South Pacific. Because many creatures living within the coral offer important benefits to the coral such as defense from coral predators and removal of sediment, this research also seeks to better understand how changes in the biodiversity and abundance of fish and invertebrates associated with corals, affect the capacity of corals to withstand future impacts, such as sedimentation and outbreaks of coral-eating seastars. Understanding whether habitat loss alters the capacity of corals to withstand stress in an increasingly stressful world is critical to devise effective strategies to manage and protect coral reefs and the many services they provide to society. Furthermore, this research facilitates restoration efforts, enhance the scientific workforce through mentorship of a diverse group of undergraduates, graduate students and a postdoctoral fellow, and engage the public in both French Polynesia and the United States in scientific research and knowledge.

Many marine systems are characterized by habitat-forming foundation species, which harbor a diversity of occupants, and whose dynamics are thought to drive resilience of entire ecosystems As a result, there is widespread concern over the ongoing loss and fragmentation of biogenic habitats such as seagrass beds, oyster reefs, kelp forests, and coral reefs. Yet, without a more complete understanding of marine landscape ecology, we struggle to predict how the degradation or restoration of habitat alters ecosystem dynamics, function, and resilience. Most research in marine landscape ecology has focused on spatial patterns of occupant abundance and biodiversity; however, the causes and consequences of these patterns are rarely explored. An important but understudied consequence of variation in occupant density is that it may alter how occupants interact with their biogenic habitat. Because occupants can benefit biogenic habitat or harm biogenic habitat, changes in occupant density can affect habitat growth and survival. Consequently, habitat-driven variation in occupant density should feed back to alter habitat dynamics and the spatial patterning of the habitat. In summary, we are limited in our understanding of why patterns in landscape ecology exist, how these patterns alter the population dynamics and spatial patterns of the occupants as well as their habitat, and the implications of habitat degradation or restoration. The central objective of this proposal is to examine the causes and consequences of the nonlinear relationship between occupant abundance and the amount of biogenic habitat. Specifically, the investigators: (i) examine the habitat-based mechanisms that produce spatial variation in occupant density; (ii) quantify how habitat-driven occupant density feeds back to alter habitat growth and survival; and (iii) apply this knowledge to understand how bidirectional habitat-occupant interactions affect the long-term dynamics, create novel spatial patterns, and drive variation in how systems respond to and recover from disturbances.

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.