Dinobryaceae algae

The Dinobryaceae family consists of colonial golden algae that, when proliferating in aquaculture systems, act as a significant stressor for aquatic organisms. While part of the natural phytoplankton, their mass development disrupts the ecological balance of production ponds.

The agent is a mixotrophic alga that forms branching colonies within cellulosic loricae. This unique physiological adaptation allows these organisms to thrive in various conditions, shifting between photosynthesis and the ingestion of organic matter, which enhances their survival in eutrophic waters.

The primary victims of Dinobryaceae outbreaks are juvenile fish in nursery and grow-out ponds. The algal bloom interferes with the fish's respiratory functions, reduces available oxygen at night due to respiration, and alters the pond's overall chemistry, potentially leading to significant growth stagnation.

Development and spread are triggered by high light intensity, moderate water temperatures, and the availability of dissolved organic nutrients. These conditions are commonly found in stagnant or low-flow ponds that have been over-fertilized or have high loads of decaying organic matter.

• Yellowish or golden discoloration of the pond water.
• Sharp fluctuations in diurnal oxygen levels, threatening fish life.
• Reduced appetite and stunted growth in fry populations.
• Potential clogging of fish gills due to heavy colonial structures.

Effective management requires maintaining precise water quality parameters and minimizing organic waste accumulation. Preventive measures include the rational use of fertilizers, efficient pond aeration, and periodic monitoring of phytoplankton density to avoid the rapid shift of the biological equilibrium towards Dinobryaceae dominance.