Science activity
Science activity #49816, updated 29 April 2022

The effects of early hypersaline acclimation due to climate change on the toxicity of pyrethroid, an insecticide, in salmonids.

Description / purpose

Sea level rise and drought are expected to result in hypersaline waterways in the Delta. Endangered Chinook salmon and Steelhead trout go through smoltification to be able to live and mature in saline environments. However, with salinities and temperatures increasing in historically freshwater areas, these fish may be facing new stressors. Pesticide runoff into the Delta is common due to the urbanization and agriculture of many regions and can adversely affect fish. Additionally, previous research has shown that salinity exposure increases the toxicity of contaminants in anadromous fish, and it is had been demonstrated that bifenthrin, a common insecticide in the Bay, can have endocrine disrupting effects on juvenile salmonids. This project will examine the impacts of hypersaline conditions, various temperatures, and exposure to bifenthrin on the development and survival of juvenile Chinook salmon and Steelhead trout. Specifically, it will: Test the impacts of premature hypersaline acclimation and temperature on the survivial and smoltification process of a range of juvenile salmonids; Test the combined impacts of premature hypersaline acclimation, temperature, and bifenthrin exposure on smoltification, survival and behavior;and Predict the population level effects of drought and pesticide runoff on the health of endangered salmonids Additionally, this research will provide information to CA Department of Pesticide Regulation for potential pesticide management in the Delta, as well as to the CA Department of Fish and Wildlife for conservation practices of endangered juvenile salmonids in the Delta.

Linked science activities

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Activity status

  • Awarded / Initiating (2016)
  • In progress / Ongoing (2016 - 2018)
  • Complete

Funding summary

Total allocated funding: $0

Label Value
Contract # or labor code None
Implementing organization California Sea Grant
Funding organization California Department of Fish and Wildlife [CDFW]
Funding Source California Department of Fish and Wildlife CDFW - Prop 1
Date of award Not provided
Date of fiscal year-end Not provided
Total award amount $0
State type of obligation Not provided
Federal type of obligation Not provided
Reimbursability Not provided
Procurement mechanism Not provided


Delta regions

Geographic tags

None specified

Products and outputs

None provided