3. VINPS (as published)

Virgin Islands National Park Service, species level, 2001 to 2023

Last updated

July 6, 2026

As published Updated since publication →

Olinger LK, Edmunds PJ, Levitan D, Smith TB, Lasker H, Feeley M, Mahoney L, Dahl A. Reproductive mode, but not rarity, influences population trajectories in corals. In Review 2026.

The coral-cover data for this analysis comes from the Reef Code benthic cover section: coral species cover download.

Summary

The Virgin Islands National Park Service program records coral cover at the species level across 7 sites around St. John and Buck Island. Broadcast spawners decline, and common brooders rise rather than fall, so reproductive mode separates the trajectories more strongly here than at the other programs. Rare and common taxa share the same proportional rate. This page renders the published analysis over its paper range, 2001 through 2023. The full analysis runs below, from the coral-cover file to the figure (Figure 1) and the statistics table (Table 1). Every step is folded. Open any block to read the code and the plain-language notes.

Set the publication parameters for this version
pub_range <- c(2001, 2023); program <- "VINPS"; taxon_level <- "species"; version <- "aspublished"
Setup: packages, color palette
suppressWarnings(suppressPackageStartupMessages({
  library(tidyverse)
  library(sandwich)
  library(lmtest)
  library(broom)
  library(patchwork)
  library(kableExtra)
}))

palette_grp <- c(
  "Common.Broadcaster" = "#0072B2", "Rare.Broadcaster" = "#56B4E9",
  "Common.Brooder"     = "#D55E00", "Rare.Brooder"     = "#E69F00"
)
label_grp <- c(
  "Common.Broadcaster" = "Common broadcaster", "Rare.Broadcaster" = "Rare broadcaster",
  "Common.Brooder"     = "Common brooder",     "Rare.Brooder"     = "Rare brooder"
)

Step 1 — Read the coral cover data

The analysis begins from the species-level coral-cover file and the site master table. The cover file holds one row per transect observation: a site, a year, a survey period, a coral species, and its percent cover. The site master holds each site’s program, depth, and the year monitoring began. The cover file is matched by pattern in data/cover/, so this step reads whichever species-level file is bundled, and the analysis grows as that file grows.

Step 1 code: read the bundled cover file (most-recent match) and the site master
cover_files <- sort(list.files("../../data/cover", pattern = "s2pt5.*\\.csv$", full.names = TRUE))
cover_file <- tail(cover_files, 1)
benthiccover <- read.csv(cover_file) |>
  select(year, program, site, period, coralSpecies, perccover)
sitedat <- read.csv("../../data/site/00_RRS_siteMaster_allSites_data.csv")
c(cover_file = basename(cover_file), cover_rows = nrow(benthiccover), sites_listed = nrow(sitedat))
                                            cover_file 
"s2pt5_benthicCoverCoralSpecies_41sites_1999_2024.csv" 
                                            cover_rows 
                                              "481351" 
                                          sites_listed 
                                                  "50" 

Step 2 — Set the scope (publication range, sites, years, taxa)

The first move is the explicit publication-range clip: every downstream step runs only on years inside pub_range. At the published range this clip is harmless, since the bundled file does not extend beyond it; as the cover file grows in later monitoring years, the same clip is what keeps this page reproducing the published analysis exactly. After the clip, the analysis holds the rest of the sampling design constant so that trends reflect coral change rather than changes in which reefs or taxa were surveyed: the VINPS sites established before 2006, and the coral species identified to species. It drops the fire corals (Millepora), the generic catch-all entries, the Orbicella complex placeholder, and any taxon left at the genus level. The shallow-site rule is applied where the cover joins the site depths, the same order as the original analysis.

Step 2 code: clip to pub_range, then restrict sites, taxa, and depth
# Publication-range clip: the explicit first step of scope.
benthiccover <- benthiccover |> filter(year >= pub_range[1], year <= pub_range[2])

# Sites: VINPS reefs established before 2006, with a depth category.
sitedat <- sitedat |>
  filter(program == "VINPS", yearadded < 2006) |>
  mutate(depth_cat = ifelse(depth < 21, "Shallow", "Deep"))

# Cover: VINPS surveys.
benthiccover <- benthiccover |>
  filter(program == "VINPS")

# Taxa: fix one spelling, drop non-species and non-coral entries, keep shallow scoped sites.
benthiccover <- benthiccover |>
  mutate(coralSpecies = ifelse(coralSpecies == "Orbicella franksii", "Orbicella franksi", coralSpecies)) |>
  filter(
    !coralSpecies %in% c("Millepora alcicornis", "Millepora complanata", "Millepora squarrosa",
                         "Coral spp.", "Branching Porites spp.", "Juvenile coral spp.", "Orbicella species complex"),
    !grepl(" spp\\.$", coralSpecies),
    site %in% sitedat$site
  ) |>
  left_join(select(sitedat, site, depth_cat), by = "site") |>
  filter(depth_cat == "Shallow")
c(cover_rows = nrow(benthiccover), sites_kept = n_distinct(benthiccover$site),
  species = n_distinct(benthiccover$coralSpecies))
cover_rows sites_kept    species 
    139993          7         49 

Validation note: the scoped dataset spans 2001 through 2023, holds 139,993 transect records across 7 VINPS sites and 49 coral species.

Step 3 — Bin years and set the baseline period

The analysis compares a baseline period to the full record. It bins the survey years into five-year groups and treats the first group as the baseline. Binning smooths the year-to-year noise in the baseline abundance ranking without changing the annual data used later in the model. The helper below builds the five-year groups from the data range and labels each year with its group.

Step 3 code: bin years into five-year groups; set the baseline
bin_years <- function(df, interval = 5) {
  min_yr <- min(df$year, na.rm = TRUE); max_yr <- max(df$year, na.rm = TRUE)
  breaks <- seq(min_yr, max_yr, by = interval)
  if (tail(breaks, 1) > max_yr - (interval - 1)) breaks <- head(breaks, -1)
  labels <- paste(breaks, pmin(breaks + (interval - 1), max_yr), sep = "-")
  map <- data.frame(year = seq(min_yr, max_yr)) |>
    mutate(year_group = cut(year, breaks = c(breaks, max_yr + 1), labels = labels,
                            right = FALSE, include.lowest = TRUE))
  df |> left_join(map, by = "year") |> mutate(year_group = as.factor(year_group))
}

benthiccover <- bin_years(benthiccover, 5)
earliest_year_group <- levels(benthiccover$year_group)[1]
# earliest_year_group

The baseline period is the first five-year group, 2001-2005. Two presence rules keep the analysis on taxa that were part of the community at baseline and at sites within their range. The first keeps species recorded during the baseline period. The second drops species-site pairs where the species was never seen, since a site outside a species range would enter the model as a structural zero rather than a decline.

Step 3 code: keep baseline-present species and in-range sites
species_yeargroup_observed <- benthiccover |>
  group_by(coralSpecies, year_group) |>
  summarize(seen = max(perccover, na.rm = TRUE) > 0, .groups = "drop") |>
  filter(seen)
spp_in_baseline <- species_yeargroup_observed |>
  filter(year_group == earliest_year_group) |>
  pull(coralSpecies) |> unique()
benthiccover <- benthiccover |> filter(coralSpecies %in% spp_in_baseline)

in_range <- benthiccover |>
  group_by(coralSpecies, site) |>
  summarize(seen = max(perccover, na.rm = TRUE) > 0, .groups = "drop") |>
  filter(seen) |> mutate(key = paste(coralSpecies, site))
benthiccover <- benthiccover |>
  filter(paste(coralSpecies, site) %in% in_range$key)

benthiccover <- benthiccover |>
  group_by(year_group, coralSpecies, year, site) |>
  summarise(perccover = mean(perccover, na.rm = TRUE), .groups = "drop")
c(rows = nrow(benthiccover), species = n_distinct(benthiccover$coralSpecies))
   rows species 
   2902      28 

Step 4 — Rank baseline abundance

Each species receives its mean percent cover during the baseline period. Ranking the species by that mean sets the order used in the figure and sets up the commonness split. The cumulative proportion of cover, summed down the ranked list, measures how much of the reef’s baseline cover the top species account for.

Step 4 code: mean baseline cover, rank, cumulative cover
baseline <- benthiccover |>
  filter(year_group == earliest_year_group) |>
  group_by(coralSpecies) |>
  summarise(meancov = mean(perccover, na.rm = TRUE), .groups = "drop") |>
  filter(meancov > 0) |>
  arrange(desc(meancov)) |>
  mutate(rank = row_number(),
         normcov = meancov / sum(meancov, na.rm = TRUE),
         cumsumcov = cumsum(normcov))
# head(baseline, 6)

Step 5 — Classify common and rare (90/10)

The commonness split follows one rule: the species that together hold the top 90 percent of baseline cumulative cover are common, and the rest are rare. The manuscript identified 0.90 through a sliding-window analysis as the strictest rarity definition that leaves the temporal slopes stable.

Step 5 code: split common from rare at 0.90 cumulative cover
baseline <- baseline |>
  mutate(commonness = ifelse(cumsumcov <= 0.900001, "Common", "Rare"))
table(baseline$commonness)

Common   Rare 
     7     21 

Step 6 — Assign reproductive mode

Each species carries a reproductive mode, brooder or broadcaster. The assignment reads a compiled trait table, drops unknown entries, and joins the mode onto the baseline species. A second trait table fills any species the first leaves unassigned. Species that still lack a mode after both sources leave the analysis, because the model compares brooders to broadcasters and cannot place an unassigned species.

Step 6 code: join reproductive mode from two trait tables
repro1 <- read.csv("../../data/collab/reproMode_coralSpecies_Mahoney_20250108.csv") |>
  rename(coralSpecies = Species) |>
  filter(Reproductive_mode %in% c("Brooder", "Broadcaster")) |>
  distinct(coralSpecies, Reproductive_mode)
repro2 <- read.csv("../../data/collab/reproMode_coralSpecies_Olinger_20250108.csv") |>
  filter(Reproductive_mode %in% c("Brooder", "Broadcaster")) |>
  distinct(coralSpecies, Reproductive_mode)

baseline <- baseline |>
  left_join(repro1, by = "coralSpecies") |>
  left_join(repro2, by = "coralSpecies", suffix = c("", ".2")) |>
  mutate(Reproductive_mode = coalesce(Reproductive_mode, Reproductive_mode.2)) |>
  select(-Reproductive_mode.2) |>
  filter(Reproductive_mode %in% c("Brooder", "Broadcaster"))
# with(baseline, table(Commonness = commonness, `Reproductive mode` = Reproductive_mode))

Step 7 — Build the analysis dataset

The model works on group means rather than individual species, so that a single abundant species cannot dominate the trend. This step joins the commonness and reproductive-mode labels onto the full cover series, averages cover within each group at each site and year, adds a year index that starts at zero, and takes the log10 of cover. Log10 cover is the response, because coral loss acts proportionally, and a proportional change is a straight line on the log scale.

Step 7 code: aggregate to group-site-year means
analysis_data <- benthiccover |>
  inner_join(baseline |> select(coralSpecies, commonness, Reproductive_mode), by = "coralSpecies") |>
  group_by(category = commonness, Reproductive_mode, year, site) |>
  summarise(perccover = mean(perccover, na.rm = TRUE), .groups = "drop") |>
  mutate(yearind = year - min(year), perccoverLog = log10(perccover)) |>
  filter(perccover > 0) |>
  mutate(category = factor(category, levels = c("Common", "Rare")),
         Reproductive_mode = factor(Reproductive_mode, levels = c("Broadcaster", "Brooder")))
c(model_rows = nrow(analysis_data), groups = nlevels(interaction(analysis_data$category, analysis_data$Reproductive_mode)))
model_rows     groups 
       569          4 

Step 8 — Fit the model

The model predicts log10 percent cover from year, commonness, reproductive mode, and every interaction among them. Common and broadcaster are the reference levels, so the year term is the trend for common broadcasters, and the interactions measure how the other groups differ from it.

Step 8 code: fit the three-way interaction model
model_full <- lm(perccoverLog ~ yearind * category * Reproductive_mode, data = analysis_data)

Step 9 — Robust standard errors

The residual variance is larger for the abundant groups than for the sparse groups, so ordinary standard errors would misstate the uncertainty. The analysis replaces them with HC3 heteroscedasticity-consistent standard errors, computed from a sandwich covariance matrix. Every standard error, p-value, and confidence interval below uses this robust covariance.

Step 9 code: HC3 robust covariance and coefficient table
vcov_hc3 <- sandwich::vcovHC(model_full, type = "HC3")
coef_robust <- broom::tidy(lmtest::coeftest(model_full, vcov = vcov_hc3))

Step 10 — Group-specific slopes

The four group trends are linear combinations of the model coefficients. The common-broadcaster slope is the year term. Each other group adds the interactions that apply to it. The standard error of each slope comes from the robust covariance, so the uncertainty carries through. Annual percent change back-transforms the log10 slope into a yearly rate.

Step 10 code: derive the four group slopes
group_slope <- function(terms) {
  L <- setNames(rep(0, length(coef(model_full))), names(coef(model_full)))
  L[terms] <- 1
  est <- sum(L * coef(model_full))
  se <- sqrt(as.numeric(t(L) %*% vcov_hc3 %*% L))
  tibble(Slope = est, SE = se, `Annual % change` = 100 * (10^est - 1),
         `P-value` = 2 * pnorm(-abs(est / se)))
}
group_slopes <- bind_rows(
  "Common broadcaster" = group_slope("yearind"),
  "Rare broadcaster"   = group_slope(c("yearind", "yearind:categoryRare")),
  "Common brooder"     = group_slope(c("yearind", "yearind:Reproductive_modeBrooder")),
  "Rare brooder"       = group_slope(c("yearind", "yearind:categoryRare",
                                       "yearind:Reproductive_modeBrooder",
                                       "yearind:categoryRare:Reproductive_modeBrooder")),
  .id = "Group"
)

Step 12 — Table: model coefficients

The table reports the model coefficients with HC3 robust standard errors and p-values. Bold marks terms significant at p less than 0.05.

Step 12 code: format the coefficient table and the group slopes
term_labels <- c(
  "(Intercept)" = "Intercept", "yearind" = "Year",
  "categoryRare" = "Rarity", "Reproductive_modeBrooder" = "Repro. mode (brooder)",
  "yearind:categoryRare" = "Year x Rarity", "yearind:Reproductive_modeBrooder" = "Year x Repro. mode",
  "categoryRare:Reproductive_modeBrooder" = "Rarity x Repro. mode",
  "yearind:categoryRare:Reproductive_modeBrooder" = "Year x Rarity x Repro. mode"
)
coef_tbl <- coef_robust |>
  transmute(Predictor = term_labels[term],
            `Estimate (SE)` = sprintf("%.3f (%.3f)", estimate, std.error),
            `P-value` = ifelse(p.value < 0.001, "< 0.001", sprintf("%.3f", p.value)),
            .sig = p.value < 0.05)

kbl(coef_tbl |> select(-.sig), align = c("l", "r", "r"),
    caption = "Table 1 (VINPS). Linear-model coefficients with HC3 robust standard errors.") |>
  kable_styling(bootstrap_options = c("striped", "hover", "condensed"), full_width = FALSE) |>
  row_spec(which(coef_tbl$.sig), bold = TRUE)
Table 1: Table 1 (VINPS). Linear-model coefficients with HC3 robust standard errors.
Predictor Estimate (SE) P-value
Intercept 0.070 (0.054) 0.200
Year -0.010 (0.004) 0.015
Rarity -1.073 (0.078) < 0.001
Repro. mode (brooder) -0.416 (0.079) < 0.001
Year x Rarity 0.004 (0.006) 0.550
Year x Repro. mode 0.027 (0.005) < 0.001
Rarity x Repro. mode -0.035 (0.115) 0.762
Year x Rarity x Repro. mode -0.023 (0.009) 0.008
Step 12 code: the four group slopes
group_slopes |>
  mutate(Slope = sprintf("%.4f", Slope), SE = sprintf("%.4f", SE),
         `Annual % change` = sprintf("%.2f", `Annual % change`),
         `P-value` = ifelse(`P-value` < 0.001, "< 0.001", sprintf("%.3f", `P-value`))) |>
  kbl(align = c("l", "r", "r", "r", "r"),
      caption = "Group-specific temporal slopes estimated by Wald tests on linear combinations of model coefficients. The annual percent change is calculated as (10^slope - 1) x 100. P-values test the null hypothesis that the total temporal slope equals zero (H0: slope = 0). Common Broadcasters are the reference group; their slope and p-value come directly from the Year coefficient.") |>
  kable_styling(bootstrap_options = c("striped", "hover", "condensed"), full_width = FALSE)
Table 2: Group-specific temporal slopes estimated by Wald tests on linear combinations of model coefficients. The annual percent change is calculated as (10^slope - 1) x 100. P-values test the null hypothesis that the total temporal slope equals zero (H0: slope = 0). Common Broadcasters are the reference group; their slope and p-value come directly from the Year coefficient.
Group Slope SE Annual % change P-value
Common broadcaster -0.0099 0.0040 -2.26 0.014
Rare broadcaster -0.0064 0.0043 -1.46 0.139
Common brooder 0.0175 0.0036 4.11 < 0.001
Rare brooder -0.0020 0.0052 -0.46 0.699

Step 13 — Table: full descriptive statistics per species

The coefficient table reports the fitted trends. This table steps back to the species themselves and reports, for every taxon in the baseline community, how abundant and how widespread it was at the start of the record and how that changed by the end. Three complementary measures separate the different ways a species can decline. Cover is the mean percent cover across the species range. Occupancy is the proportion of surveyed sites where the species was present, so it tracks range contraction independent of local abundance. Extent is the mean cover at the sites where the species was actually present, so it tracks thinning within the occupied range. A species can hold its occupancy while its extent falls, or contract its range while staying dense where it persists; reporting both separates the two. Start values average over the baseline five-year group, and end values average over the last three years of the record. Occupancy counts a site only from the year it entered monitoring, so the denominator follows the site-by-site survey history rather than assuming every reef was watched from the first year.

Step 13 code: per-species descriptive change-metrics table
source("../../_includes/_analysis_helpers.R")
species_table <- compute_change_metrics(benthiccover, baseline, sitedat, earliest_year_group, "coralSpecies")

.end_yrs <- (max(benthiccover$year) - 2):max(benthiccover$year)
.desc_tbl <- species_table |>
  arrange(rank_start) |>
  transmute(
    Species = taxon,
    `Repro. mode` = mode,
    Commonness = commonness,
    `Start rank` = rank_start,
    `End rank` = ifelse(is.na(rank_end), "-", as.character(rank_end)),
    `Start cover (%)` = sprintf("%.2f", cover_start),
    `End cover (%)` = ifelse(is.na(cover_end), "-", sprintf("%.2f", cover_end)),
    `Start occ. (%)` = sprintf("%.1f", occ_start),
    `End occ. (%)` = sprintf("%.1f", occ_end),
    `Start extent (%)` = ifelse(is.na(ext_start), "-", sprintf("%.2f", ext_start)),
    `End extent (%)` = ifelse(is.na(ext_end), "-", sprintf("%.2f", ext_end)),
    .common = commonness == "Common"
  )
kbl(.desc_tbl |> select(-.common), align = c("l", "l", "l", rep("r", 8)),
    caption = sprintf(
      "Descriptive statistics for coral species in the VINPS monitoring program. Species are ordered by their rank in the baseline period. Reproductive Mode ('Repro. Mode') indicates reproductive strategy. Rows in bold signify common species, determined by the top 90%% cumulative cover threshold during the baseline period (%s). Start Cover (%%), Start Occupancy (Start Occup. (%%)), Start Extent (%%), and Start Rank are metrics from the baseline period. End Cover (%%), End Occupancy (End Occup. (%%)), End Extent (%%), and End Rank are metrics for the recent period (%d-%d).",
      earliest_year_group, min(.end_yrs), max(.end_yrs))) |>
  kable_styling(bootstrap_options = c("striped", "hover", "condensed"), full_width = FALSE) |>
  column_spec(1, italic = TRUE) |>
  row_spec(which(.desc_tbl$.common), bold = TRUE)
Table 3: Descriptive statistics for coral species in the VINPS monitoring program. Species are ordered by their rank in the baseline period. Reproductive Mode ('Repro. Mode') indicates reproductive strategy. Rows in bold signify common species, determined by the top 90% cumulative cover threshold during the baseline period (2001-2005). Start Cover (%), Start Occupancy (Start Occup. (%)), Start Extent (%), and Start Rank are metrics from the baseline period. End Cover (%), End Occupancy (End Occup. (%)), End Extent (%), and End Rank are metrics for the recent period (2021-2023).
Species Repro. mode Commonness Start rank End rank Start cover (%) End cover (%) Start occ. (%) End occ. (%) Start extent (%) End extent (%)
Orbicella annularis Orbicella annularis Broadcaster Common 1 1 6.76 1.84 100.0 76.2 6.76 2.42
Orbicella franksi Orbicella franksi Broadcaster Common 2 4 1.44 0.60 73.1 71.4 1.58 0.83
Porites porites Porites porites Brooder Common 3 3 0.91 0.76 84.8 76.2 1.06 1.00
Montastraea cavernosa Montastraea cavernosa Broadcaster Common 4 8 0.55 0.05 100.0 66.7 0.55 0.08
Porites astreoides Porites astreoides Brooder Common 5 2 0.54 0.91 100.0 76.2 0.54 1.19
Siderastrea siderea Siderastrea siderea Broadcaster Common 6 5 0.46 0.22 100.0 76.2 0.46 0.29
Pseudodiploria strigosa Pseudodiploria strigosa Broadcaster Common 7 9 0.36 0.03 75.5 38.1 0.48 0.09
Agaricia agaricites Agaricia agaricites Brooder Rare 8 6 0.33 0.21 100.0 71.4 0.33 0.29
Orbicella faveolata Orbicella faveolata Broadcaster Rare 9 7 0.24 0.21 60.3 76.2 0.40 0.27
Colpophyllia natans Colpophyllia natans Broadcaster Rare 10 11 0.21 0.02 81.5 28.6 0.26 0.06
Diploria labyrinthiformis Diploria labyrinthiformis Broadcaster Rare 11 13 0.15 0.01 95.0 23.8 0.15 0.04
Dichocoenia stokesii Dichocoenia stokesii Broadcaster Rare 12 - 0.11 0.00 22.5 0.0 0.16 -
Dendrogyra cylindrus Dendrogyra cylindrus Broadcaster Rare 13 - 0.09 0.00 28.7 0.0 0.12 -
Madracis mirabilis Madracis mirabilis Brooder Rare 14 12 0.05 0.01 31.4 28.6 0.07 0.04
Acropora cervicornis Acropora cervicornis Broadcaster Rare 15 - 0.03 0.00 15.7 0.0 0.04 -
Meandrina meandrites Meandrina meandrites Broadcaster Rare 16 16 0.02 0.00 34.2 4.8 0.06 0.05
Stephanocoenia intercepta Stephanocoenia intercepta Broadcaster Rare 17 10 0.02 0.03 36.0 57.1 0.07 0.06
Eusmilia fastigiata Eusmilia fastigiata Broadcaster Rare 18 19 0.02 0.00 48.2 4.8 0.04 0.03
Mycetophyllia lamarckiana Mycetophyllia lamarckiana Brooder Rare 19 - 0.01 0.00 19.0 0.0 0.03 -
Madracis decactis Madracis decactis Brooder Rare 20 14 0.01 0.01 23.7 28.6 0.04 0.03
Mycetophyllia ferox Mycetophyllia ferox Brooder Rare 21 - 0.01 0.00 9.7 0.0 0.03 -
Pseudodiploria clivosa Pseudodiploria clivosa Broadcaster Rare 22 - 0.01 0.00 3.3 0.0 0.04 -
Favia fragum Favia fragum Brooder Rare 23 - 0.01 0.00 18.5 0.0 0.02 -
Mycetophyllia aliciae Mycetophyllia aliciae Brooder Rare 24 15 0.00 0.01 9.0 14.3 0.02 0.04
Isophyllia sinuosa Isophyllia sinuosa Brooder Rare 25 - 0.00 0.00 3.3 0.0 0.02 -
Porites furcata Porites furcata Brooder Rare 26 17 0.00 0.00 8.0 9.5 0.02 0.02
Helioseris cucullata Helioseris cucullata Brooder Rare 27 18 0.00 0.00 7.3 9.5 0.02 0.02
Siderastrea radians Siderastrea radians Brooder Rare 28 - 0.00 0.00 2.9 0.0 0.02 -

Step 14 — Save the analysis objects

The analysis objects are written to a timestamped RData file under data/rdata/, tagged with the program and the version (as published or updated) so the two ranges never overwrite each other. The manuscript-values page loads the most recent file for each program and version and reads every derived number from these saved objects, rather than repeating the computation. The derived CSVs written elsewhere are left unchanged.

Step 15 — SI table: taxa excluded from the trend analysis

The trend model runs only on species that were part of the baseline community, so that a modeled slope reflects a species present at the outset rather than one that arrived mid-record. Some species were observed at least once during the record but not during the baseline period, or could not be assigned a reproductive mode; those are held out of the trend analysis and listed here with the year each was first observed.

Step 15 code: taxa observed but absent from the baseline community
.excl <- excluded_taxa_table(species_yeargroup_observed, baseline$coralSpecies, "coralSpecies")
kbl(.excl, align = c("l", "r"),
    caption = "Taxa excluded from trend analyses because they were not recorded during the baseline period (2001–2005 for TCRMP and VINPS; 1992–1996 for CSUN). For each taxon, the program and year of first observation at shallow monitoring sites are shown. CSUN taxa are at the genus level; TCRMP and VINPS taxa are at the species level.") |>
  kable_styling(bootstrap_options = c("striped", "hover", "condensed"), full_width = FALSE) |>
  column_spec(1, italic = TRUE)
Table 4: Taxa excluded from trend analyses because they were not recorded during the baseline period (2001–2005 for TCRMP and VINPS; 1992–1996 for CSUN). For each taxon, the program and year of first observation at shallow monitoring sites are shown. CSUN taxa are at the genus level; TCRMP and VINPS taxa are at the species level.
Taxon Year first observed
Acropora palmata 2006
Agaricia fragilis 2016
Agaricia grahamae 2011
Agaricia humilis 2011
Agaricia lamarcki 2006
Agaricia tenuifolia 2011
Agaricia undata 2011
Isopyhyllastrea rigida 2006
Scolymia cubensis 2011

Step 16 — SI figure: model diagnostics

The coefficient table uses HC3 robust standard errors because the residual variance is not constant across groups. These diagnostic panels show why. Residuals versus fitted values reveal the unequal spread, the normal Q-Q plot shows the tails, and the residual distribution summarizes the whole. The robust standard errors used throughout the analysis are the response to exactly this structure.

Step 16 code: model diagnostics from the fitted model
model_diagnostics_plot(model_full)
Figure 2: Diagnostic plots for linear models of log₁₀-transformed coral cover. Models were fit independently for (A-C) TCRMP species-level data, (D-F) VINPS species-level data, and (G-I) CSUN genus-level data. Columns from left to right display: Residuals versus fitted values plots, which are used to assess linearity of relationships and homogeneity of variance (homoscedasticity); Normal Q-Q (quantile-quantile) plots of standardized residuals, used to assess the normality of the residuals by comparing their distribution to a theoretical normal distribution; and Histograms of standardized residuals with an overlaid kernel density estimate (blue line), providing a visual representation of the distribution of residuals, further aiding in the assessment of normality.