Researchers who simulated excess amounts of Polynuclear aromatic hydrocarbons (PAHs) derived from fossil fuels, in a watershed, found it to adversely affect salmon populations.
In a new study published in Integrated Environmental Assessment and Management (IEAM), PAH contamination was simulated for a single pink salmon population in an Alaskan watershed. This salmon population has been monitored almost continuously for 70 years, since 1934.
The size of the salmon diminished as their natal habitat became increasingly contaminated, indicating increased vulnerability to extinction.
According to the study's author Ron Heintz, of the Alaska Fisheries Science Center and National Oceanic and Atmospheric Administration Fisheries, managers should view salmon populations in decline with a great deal of concern, especially populations exposed to PAHs and other contaminants during sensitive life stages.
Management actions in such cases would be prudent given that once significant population declines have been detected in a population it may be too late to prevent further declines.