{
  "version": "1.0.0",
  "checked": "2026-10-21",
  "annual": [
    {
      "forecast_sqmi": 4880,
      "lower_sqmi": 2150,
      "upper_sqmi": 7580,
      "observed_sqmi": 6334,
      "may_nitrate_tonnes": 90500,
      "may_phosphorus_tonnes": 15600,
      "year": 2021,
      "forecast_source": "https://cdn.coastalscience.noaa.gov/page-attachments/news/2021_Hypoxia_OnePager.pdf",
      "survey_source": "https://www.noaa.gov/news-release/larger-than-average-gulf-of-mexico-dead-zone-measured"
    },
    {
      "forecast_sqmi": 5364,
      "lower_sqmi": 2662,
      "upper_sqmi": 8041,
      "observed_sqmi": 3275,
      "may_nitrate_tonnes": 102000,
      "may_phosphorus_tonnes": 20000,
      "year": 2022,
      "forecast_source": "https://cdn.coastalscience.noaa.gov/page-attachments/news/2022_Hypoxia_OnePager.pdf",
      "survey_source": "https://www.noaa.gov/news-release/below-average-gulf-of-mexico-dead-zone-measured"
    },
    {
      "forecast_sqmi": 4155,
      "lower_sqmi": 1646,
      "upper_sqmi": 6657,
      "observed_sqmi": 3058,
      "may_nitrate_tonnes": 76700,
      "may_phosphorus_tonnes": 16300,
      "year": 2023,
      "forecast_source": "https://cdn.coastalscience.noaa.gov/page-attachments/Forecast/2023HypoxiaOnePager.pdf",
      "survey_source": "https://www.noaa.gov/news-release/noaa-and-partners-announce-below-average-dead-zone-measured-in-gulf-of-mexico"
    },
    {
      "forecast_sqmi": 5827,
      "lower_sqmi": 3266,
      "upper_sqmi": 8370,
      "observed_sqmi": 6705,
      "may_nitrate_tonnes": 121500,
      "may_phosphorus_tonnes": 21000,
      "year": 2024,
      "forecast_source": "https://cdn.coastalscience.noaa.gov/page-attachments/Forecast/2024HypoxiaOnePager.pdf",
      "survey_source": "https://www.noaa.gov/news-release/gulf-of-mexico-dead-zone-larger-than-average-scientists-find"
    },
    {
      "forecast_sqmi": 5574,
      "lower_sqmi": 2839,
      "upper_sqmi": 8237,
      "observed_sqmi": 4402,
      "may_nitrate_tonnes": 99300,
      "may_phosphorus_tonnes": 22600,
      "year": 2025,
      "forecast_source": "https://cdn.coastalscience.noaa.gov/page-attachments/Forecast/2025GulfofAmericaHypoxiaOnePager.pdf",
      "survey_source": "https://www.noaa.gov/news-release/gulf-of-america-dead-zone-below-average-scientists-find"
    },
    {
      "forecast_sqmi": 7027,
      "lower_sqmi": 3895,
      "upper_sqmi": 10021,
      "observed_sqmi": 1332,
      "may_nitrate_tonnes": 134500,
      "may_phosphorus_tonnes": 16300,
      "year": 2026,
      "forecast_source": "https://cdn.coastalscience.noaa.gov/page-attachments/Forecast/2026GulfofAmericaHypoxiaOnePager.pdf",
      "survey_source": "https://www.noaa.gov/news-release/noaa-and-partners-find-smaller-than-anticipated-hypoxic-zone-in-gulf-of-america"
    }
  ],
  "reported_2026_five_year_mean_sqmi": 3745,
  "target_five_year_mean_sqmi": 1900,
  "fish_source": "https://repository.library.noaa.gov/view/noaa/25959",
  "fish_doi": "10.1007/s12237-019-00626-x",
  "fish_cruises": [
    "2006-08-04 through 2006-08-13",
    "2007-07-30 through 2007-10-14",
    "2008-08-01 through 2008-08-11"
  ],
  "fish_effort": [
    {
      "category": "Above fitted CPUE breakpoint (>1.15 mg/L)",
      "trawls": 91,
      "minutes": 1707
    },
    {
      "category": "At/below fitted CPUE breakpoint (\u22641.15 mg/L)",
      "trawls": 46,
      "minutes": 943
    }
  ],
  "breakpoints": [
    {
      "endpoint": "Fish community / CPUE",
      "mg_l": 1.15,
      "lower": 0.99,
      "upper": 3.24
    },
    {
      "endpoint": "Diet composition",
      "mg_l": 1.71,
      "lower": 0.98,
      "upper": 3.33
    }
  ],
  "diet_tests": [
    {
      "group": "Zooplankton feeders",
      "F": 8.75,
      "df": "1,138",
      "p": 0.001
    },
    {
      "group": "Bottom-prey feeders",
      "F": 2.36,
      "df": "1,90",
      "p": 0.03
    },
    {
      "group": "Fish / mobile-prey feeders",
      "F": 1.53,
      "df": "1,71",
      "p": 0.2
    }
  ],
  "fish_sample_note": "Table 1 lists 144 red snapper caught; this is not the number of replicated experimental treatments, adult reef fish, or individual stomachs in an independent-effects model. The authors averaged same-species stomach biomass within each trawl."
}