Estimated Annual Economic Impacts from Harmful Algal Blooms (HABs) in the United States

摘要

Blooms of toxic or harmful microalgae, commonly called 'red tides', represent a significant - and expanding threat to human health and fisheries resources throughout the United States and the world. These phenomena take many forms, ranging from massive accumulations of cells that discolor the water to dilute, inconspicuous, but highly toxic populations. Ecological, aesthetic, and public health impacts include: mass mortalities of wild and farmed fish and shellfish; human intoxication and death from the consumption of contaminated shellfish or fish; alterations of marine food webs through adverse effects on larvae and other life history stages of commercial fish species; the noxious smell and appearance of algae accumulated in nearshore waters or deposited on beaches; and mass mortalities of marine mammals, seabirds, and other animals. Many harmful algal blooms (HABs) have significant economic impacts. Shellfish closures, wild or farmed fish mortalities, and scared consumers who avoid seafood are well-recognized impacts of major HABs. While adverse health effects and lost sales of fish and shellfish products are direct costs, constrained development or investment decisions in coastal aquaculture due to the threat from outbreaks of toxic algae are examples of poorly understood or poorly quantified indirect or hidden costs. Lost marine recreational opportunities also are a significant cost of harmful algal bloom incidents. HABs have increased steadily in both species complexity and geographical extent over the last several decades. In turn, the range of harmful effects and the magnitude of economic costs have also widened. This report provides the first comprehensive estimate of the economic impacts of HABs in the United States, focusing on both direct and indirect costs.