Massive fish die-offs have been caused by HABs. In 2016, 23 million salmon which were being farmed in Chile died from a toxic algae bloom. To get rid of the dead fish, the ones fit for consumption were made into fishmeal and the rest were dumped 60 miles offshore to avoid risks to human health. The economic cost of that die-off is estimated to have been $800 million. Environmental expert Lester Brown has written that the farming of salmon and shrimp in offshore ponds concentrates waste, which contributes to eutrophication and the creation of dead zones.
Other countries have reported similar impacts, with cities such as Rio de Janeiro, Brazil seeing major fish die-offs from blooms becoming a common occurrence. In early 2015, Rio collected an estimated 50 tons of dead fish from the lagoon where water events in the 2016 Olympics were planned to take place.
The Monterey Bay has suffered from harmful algal blooms, most recently in 2015: "Periodic blooms of toxin-producing Pseudo-nitzschia diatoms have been documented for over 25 years in Monterey Bay and elsewhere along the U.S. west coast. During large blooms, the toxin accumulates in shellfish and small fish such as anchovies and sardines that feed on algae, forcing the closure of some fisheries and poisoning marine mammals and birds that feed on contaminated fish." Similar fish die-offs from toxic algae or lack of oxygen have been seen in Russia, Colombia, Vietnam, China, Canada, Turkey, Indonesia, and France.