Primary fecundity was assessed for Acropora cervicornis corals with known disease susceptibility. This dataset presents information on oocyte sizes from dissections of coral polyps from five adult colonies containing 12 genets held in Mote Marine Lab’s spawning nurseries.

Table of Contents

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

This dataset is part of a larger study of Acropora cervicornis (staghorn) corals studied at Mote Marine Lab’s Elizabeth Moore International Center for Coral Reef Research and Restoration. We present dissection information on the sizes of oocytes measured from five randomly chosen oocytes for each of five replicate polpys from three fragments of five colonies containing 12 different genets of Acropora cervicornis held in Mote Marine Laboratory's Sand Key spawing nursery.

The project's additional analyses are listed here, and links to other data from this study can be found in the Related Datasets section below.

Analyses undertaken include:

1. Total Population (Colony size dataset)
2. Morphometric Assessment (Colony size dataset)
3. Primary Fecundity Analysis (Colony size dataset's population subset, Polyps dataset)
4. Dissections (this dataset; plus Oocyte number dataset)
5. Secondary Fecundity Analysis (Gamete bundle dataset)

See Related Datasets section below for links to above mentioned datasets.

Sampling of Acropora cervicornis coral genotypes took place at Mote Marine Lab's spawning nurseries at Sand Key (24.45782, -81.88595) and Looe Key (24.56257, -81.40009).  Primary fecundity analysis involved sampling corals with known disease susceptibility and/or resistance, measuring their size, and counting and analyzing their oocytes. 

Sampling for Primary Fecundity Analysis: 
On July 3, 2020, from 5 colonies of every genet, 3 linear branches (~10 cm in length) were sampled using bone cutters from the central portion of each colony (N=180 branches). Using a ruler, the number of polyps per one square centimeter was recorded from every branch near the base of the fragment (Polyps per Area dataset, https://www.bco-dmo.org/dataset/868308). The top ~2 cm (sterile zone) of every branch was removed before placing into a 50 mL falcon tube with 10% formalin to fix tissues. After 2 days, the formalin solutions were replaced with a 5% HCl solution, with every branch and tube triple rinsed with DI water in between to remove excess formalin. After 3 days, the 5% HCl solution in every tube was replaced with 10% HCl and subsequently refreshed every 2-3 days until branches were completely decalcified. Once decalcified, samples were triple rinsed in DI water and returned to their tubes with 70% EtOH for storage until dissection.

Dissections (this dataset):
Under a dissecting microscope, every fragment was dissected using scalpel and forceps to haphazardly select 5 polyps per fragment (N = 900 polyps) to count the total number of oocytes within each polyp (Oocyte Number Dataset, https://www.bco-dmo.org/dataset/867314).  From those, 5 oocytes were randomly selected to measure their size under a compound microscope using an ocular micrometer to record the maximum diameter (length, d1) and its perpendicular diameter (width, d2). The volume of oocytes was calculated using the formula for a prolate ellipsoid: V= (4/3)*pi*(d1/2)*(d2/2)^2

Calibration factor: Oocytes were measured using a 10x ocular micrometer and 4x objective (total 40X) and a calibration factor was applied using the formula: V= (4/3)*pi*((d1/2)*250)*((d2/2)*250)^2 and converted to the units, mm3, for final values.

Problem report: 
Genet 31: In the time between when the parental colonies were morphometrically assessed/sampled in the Sand Key nursery for the primary fecundity analysis and brought into the lab for spawning/sampled for the secondary fecundity analysis, the entire tree for genet 31 snapped off from its anchor and went missing. As such, 5 colonies of genet 31 were brought in from a different spawning nursery and location (Looe Key Nursery: 24.56257, -81.40009). Thus, the fecundity data obtained from the fragments and gamete bundles come from different subpopulations (fragments from Sand Key and gamete bundles from Looe Key).

Data were compiled into Excel (Microsoft Office) and analyzed using R version 4.0.3 (2020-10-10) -- "Bunny-Wunnies Freak Out". Nonparametric statistical and correlation analyses were conducted.

BCO-DMO Processing:
- separated Latitude and Longitude into separate columns
- added conventional header with dataset name, PI name, version date
- modified parameter names to conform with BCO-DMO naming conventions

Coverage: Florida Keys, Summerland Key, FL 24.563595°, -81.278572°

NSF Award Abstract:
Caribbean staghorn coral was one of the most common corals within reefs of the Florida Keys several decades ago. Over the last 40 years disease, bleaching, overfishing and habitat degradation caused a 95% reduction of the population. Staghorn coral is now listed as threatened under the U.S. Endangered Species Act of 1973. Within the past few years, millions of dollars have been invested for the purpose of restoring the population of staghorn coral within Florida and the U.S. Virgin Islands. Significant effort has been placed on maintaining and propagating corals of known genotypes within coral nurseries for the purpose of outplanting. However, little is known about the individual genotypes that are currently being outplanted from nurseries onto coral reefs. Are the genotypes being used for outplanting resilient enough to survive the three major stressors affecting the population in the Florida Keys: disease, high water temperatures, and ocean acidification? The research within the present study will be the first step in answering this critically important question. The funded project will additionally develop a research-based afterschool program with K-12 students in the Florida Keys and U.S. Virgin Islands that emphasizes an inquiry-based curriculum, STEM research activities, and peer-to-peer mentoring. The information from the present study will help scientists predict the likelihood of species persistence within the lower Florida Keys under future climate-change and ocean-acidification scenarios. Results of this research will also help guide restoration efforts throughout Florida and the Caribbean, and lead to more informative, science-based restoration activities.

Acropora cervicornis dominated shallow-water reefs within the Florida Keys for at least the last half a million years, but the population has recently declined due to multiple stressors. Understanding the current population level of resilience to three major threats - disease outbreaks, high water temperatures, and ocean acidification conditions - is critical for the preservation of this threatened species. Results from the present study will answer the primary research question: will representative genotypes from the lower Florida Keys provide enough phenotypic variation for this threatened species to survive in the future? The present proposal will couple controlled laboratory challenge experiments with field data and modeling applications, and collaborate with local educators to fulfill five objectives: 1) identify A. cervicornis genotypes resistant to disease, 2) identify A. cervicornis genotypes resilient to high water temperature and ocean acidification conditions, 3) quantify how high water temperature and ocean acidification conditions impact disease dynamics on A. cervicornis; 4) determine tradeoffs in life-history traits because of resilience factors; and 5) apply a trait-based model, which will predict genotypic structure of a population under different environmental scenarios.