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Live Dinophysis Bloom Map · Ireland

Weekly bloom risk for Irish shellfish sites, built on Marine Institute open data.

An léarscáil bheoThe live map Plankton counts, not toxin results · not official adviceFull screen ↗
Taiscéal an vicíExplore the wiki TurasTake the guided tour

By Garry Lohan and Felix Sproll · Ag faire ar an bhfarraige (Watching the sea)

Conas í a léamhHow to read the map

Each dot is a Marine Institute phytoplankton monitoring station in a shellfish production area. Its colour shows the chance that Dinophysis, the dinoflagellate that is the main source of diarrhetic shellfish poisoning (DSP) toxins in Irish shellfish, reaches the 100 cells/L trigger level there in the next two weeks. A new outlook is issued every week. These are cell-count forecasts, not toxin results.

OutlookThis week’s picture, site by site. BaysA short weekly note for each bay. Season replayWatch a past season unfold week by week. Bloom → toxinHow blooms run ahead of toxins in shellfish.

An séasúrThe season at a glance

Blooms are rare before May, rise through May, peak from early June to mid-July (about one in five site-weeks), and fade through September and October. An area’s first bloom of the season usually arrives in mid to late June (median ISO week 25).

Every spoke is one week of the year. Its length shows how often a monitoring site saw Dinophysis reach 100 cells per litre within the following fortnight, across the 2016–2026 season replay on the map.

  • Peak season: early June to mid-July, when about one in five site-weeks had a bloom ahead.
  • First bloom of the season: usually mid to late June (median week 25; middle half weeks 22–28, across 661 area-seasons since 2003).
  • This week is marked on the dial.

Ag tuileadh agus ag trá a chaitheann an fharraige an lá.

The sea spends the day flowing in and ebbing out. Seanfhocal

Watch a season unfold in the replay →

TorthaíWhat we found

Tástálacha
125

tests run

Every experiment, with its verdict, searchable and filterable in the wiki.

Browse the test log → Gach toradh
64

null results reported

All results are reported, including ideas that did not add skill. They show which claims the evidence does not support.

See the nulls → An Fhrainc
551

French sites: the method travels

The same approach also works on France’s much longer record (1987–2022).

Read the France page → Tonnta teasa mara
+29 days a decade

Marine heatwaves

Heatwaves around Ireland are becoming more frequent, but we found no detectable effect on plankton or toxic blooms.

See the verdict → Tocsainí eile
ASP · PSP · AZP

Other toxins & species

The scallop toxin (ASP) looks promising; paralytic (PSP) and azaspiracid (AZP) toxins showed no gain.

Explore other toxins →

An raibh a fhios agat?Did you know?

90% vs 2%A Monday sample is public in time for Sunday’s outlook 90% of the time; a Thursday sample just 2%. The day of sampling matters more than turnaround time. “+40%” → no effectThe popular “40% more blooms in heatwaves” disappears once you compare the same site in the same month. +82%Inside sheltered shellfish bays, temperature loggers record a median 82% more heatwave days than satellites see. 15.3% vs 3%When mussels are over the toxin limit, oysters are too 15.3% of the time in France, but only 3% in Ireland.

What we can say

  • The weekly outlook ranks the coming fortnight’s bloom weeks better than simply going by the usual pattern for each site and time of year.
  • The signal comes from recent plankton counts at and near each site.
  • Sea temperature, heatwaves, wind, chlorophyll, currents and rivers did not add to it.

Results in the wiki →

What we can’t say (yet)

  • It does not catch more shellfish closures than a simple trigger-level rule (≥100 cells/L at the site last week); its edge is far fewer false alarms.
  • So far it has been tested on past seasons. Live scoring starts 25 Oct 2026, with 2027 as the confirmatory season.

All caveats →

FúinnAbout

PA-Marine-Model is a research prototype by Garry Lohan and Felix Sproll. It is not an official product or official advice; shellfish safety is decided by official monitoring.

Data source: Marine Institute national phytoplankton and biotoxin monitoring programme, via MI ERDDAP (phytoplankton counts CC BY 4.0; biotoxin and status data free to use under the ERDDAP terms, not for legal use). Also E.U. Copernicus Marine Service information and other open data. Beyond the live map, this site shows national, regional and yearly aggregates only. Data sources & licences · Credits

Comharsana na farraige · Neighbours of the sea (hover or tap for the Irish names)

Demo purposes only. Research prototype by Garry Lohan and Felix Sproll. Not an official product.