Marine Institute

Weekly HAB Bulletin

Our HAB Bulletins provide information on the potential development of toxic and/or harmful phytoplankton.

Browse our latest weekly HAB Bulletins below




View daily forecast of water movement off SW coast Ireland (3-day model forecast)

Satellite data (surface chlorophyll) processed by the MI and used in the bulletin comes from data products developed by Ifremer/ DYNECO and CERSAT in Brest and NASA 

Browse past weekly HAB Bulletins

 Picture showing the colours of Algal Blooms at sea. Photo credits: See list below image

Photo credits:


  • Large blooms of Karenia brevis occurred in Florida, USA during 2005, resulting in large fish kills. Photos: C. Heil.
  • Foams of the haptophytes, Phaeocystis may be caused by the exudation of protein-rich foams by the algae. Photo: V. Rousseau, courtesy of the EUROHAB Science Initiative, 1999.The change in N:P ratio is related to Phaeocystis blooms in Dutch coastal waters. From Anderson et al. 2002, based on Riegman, 1995.
  • Alexandrium taylori bloom, Catalan coast of Spain. Photo: M. Estrada.
  • Karenia mikimotoi bloom, East China Sea, summer 2005. Photo: J. Li.
  • Noctiluca bloom, Hood Canal, Washington, USA, Summer 2005. Photo: W. Palsson, WDFW.
  • Dinophysis bloom in coastal Norway. Photo: Havforskningsinstituttet, Institute of Marine Research.

Source: NOAA,

  • Karenia brevis 'red tide' off North Carolina coast, 1987. Photo: Unknown.
  • Karenia brevis red tide off South Padre Island, coast of Texas, October 2009. Photo: Chase Fountain, Texas Department of Wildlife.
  • Bloom of Noctiluca scintillans stretched for more than 20 miles along the southern California coast. Photo: PJS Franks.
  • Ceratium furca Bloom: Pago Pago, American Samoa. Photo: Dr. Don Vargo.