Water Quality in Salmon Habitat: Nat Scholz, NOAA
He is looking at environmental health impacts from toxic runoff – what are they, how can they be effectively minimized and are ongoing efforts reducing impacts?
His group of scientists work on pollution you don’t see – metals, pharmaceuticals, insecticides, etc.
Case Study: coho salmon
NOAA and partners have targeted science on eggs, alvins, juvenile and returning adults. His presentation today will focus results of returning adults.
He started getting phone calls about finding symptomatic coho spawners – loss of orientation and died within a few hours. Coho spawner mortality surveys were conducted from 2002-2012
The mortality was highly consistent from multiple streams over time. They watched females and determined a suite of symptoms over the years. Coho were affected but not the chum spawners.
Common points found about study: adult spawners dying each fall, widespread in urban watersheds and mortality rates are high. Scientists started to ask themselves if there were differences between watersheds that could help predict prespawn mortality and found that spawner mortality correlates with landcover.
In Fall 2012: They asked the question – is exposure to urban runoff sufficent to cause coho pre spawn mortality?
Story published about the study: http://nwifc.org/2012/12/grovers-creek-coho-used-for-stormwater-runoff-experiment/
They are refining their modeling such as landcover modeling and expanding the forensics (studying gill, heart and liver tissues).