Golden Alga

January 27-31, 2009: Golden Alga (Prymnesium parvum) International Symposium

Management Data Series 236: Management of Prymnesium parvum at Texas State Fish Hatcheries

Current Bloom Status

What is Golden Alga (Prymnesium parvum)?

Photo: Dr. Carmelo Tomas UNC Wilmington

A naturally occurring microscopic flagellated alga that typically occurs in brackish waters
Under certain environmental stresses, this alga can produce toxins which can cause massive fish and bivalve (i.e. clams and mussels) kills
There is no evidence these toxins harm other wildlife, livestock or humans
Research is under way to better understand, detect and manage Golden Alga blooms

Fish kills from the golden alga, Prymnesium parvum, have been documented in inland waters in Texas since 1985. While originally noted in the Pecos River in the Rio Grande Basin, the alga has also caused fish kills in four other river basins (Brazos, Canadian, Colorado, and Red River Basins) in Texas. This algal species is found worldwide in estuarine waters (estuaries are mixing zones between freshwater from rivers and seawater) and in some freshwater bodies that have relatively high salt content. Texas biologists were the first to note the occurrence of this alga in freshwater bodies in the Western Hemisphere. Subsequently, other states have reported its occurrence or possible occurrence. Fish kills caused by the alga can be significant, resulting in ecological and economic harm to the affected waterbodies.

Frequently Asked Questions

Aditional Information:

Would you like to know more?
The Biology of Golden Alga summarizes what we know about the alga and its toxins.

Where does golden alga fit compared to other single-celled organisms?
The Golden Alga Family Tree gives examples of and information about golden alga and other protists.

What does golden alga look like?
TPWD Golden Alga Images has photos of fish kills, golden algal cells, and short videos of live golden alga. These images may be used for noncommercial/educational purposes as long as TPWD is given credit and other site policies are followed.

Golden Alga Information Card: TPWD has collaborated with TCEQ and other entities to produce a golden alga information card(pdf document). The purpose of this card is to educate the public on golden alga blooms and answer some common questions. Hard copies of this card are available for free by contacting Meridith Byrd at 361.983.1215.