

NOAA Fisheries and the U.S. Fish and Wildlife Service are responsible for protecting species that are listed as endangered or threatened under the Endangered Species Act and for protecting habitats that are critical for their survival. The U.S. Environmental Protection Agency is responsible for registering or reregistering pesticides under the Federal Insecticide, Fungicide, and Rodenticide Act and must ensure that pesticide use does not cause any unreasonable adverse effects on the environment, which includes listed species and their designated critical habitat. The agencies have developed their own approaches to evaluating environmental risk, and their approaches differ because their legal mandates, responsibilities, institutional cultures, and expertise differ. Over the years, the agencies have tried to resolve their differences but have been unsuccessful in reaching consensus regarding their assessment approaches.
As a result, NOAA Fisheries, U.S. Fish and Wildlife Service, U.S. Environmental Protection Agency, and the U.S. Department of Agriculture asked the National Research Council at the National Academy of Sciences to examine scientific and technical issues related to determining the risks that pesticides pose to listed species. Specifically, the National Research Council was asked to:
The National Research Council Committee on Ecological Risk Assessment under the Federal Insecticide, Fungicide, and Rodenticide Act and Endangered Species Act responded to that request by releasing the April 2013 report, Assessing Risks to Endangered and Threatened Species from Pesticides.
NOAA Fisheries, U.S. Fish and Wildlife Service, U.S. Environmental Protection Agency, and the U.S. Department of Agriculture have worked collaboratively and expeditiously to review the report and identify improvements in the current scientific procedures used to evaluate the potential impacts of pesticides to endangered and threatened species. The federal agencies developed an implementation plan with a timeline and approach for responding to National Academy of Science’s recommendations.
The following links provide information about our joint efforts with the other agencies to review and implement the National Academy of Science report recommendations:
You can also find more information about these efforts in the sections below on this webpage.
The U.S. Environmental Protection Agency completed biological evaluations for chlorpyrifos, diazinon, and malathion in January 2017. NOAA Fisheries issued a final biological opinion to the U.S. Environmental Protection Agency in December 2017: Chlorpyrifos, diazinon, and malathion (PDF, 3,749 pages).
In November 2014, government agencies, rice growers, and industry collaborated to protect Endangered Species Act-listed salmon and steelhead trout in California by restricting use of the pesticide thiobencarb.
In October 2014, the U.S. Fish and Wildlife Service, U.S. Environmental Protection Agency, and the U.S. Department of Agriculture, and NOAA Fisheries held a workshop to provide feedback on assessing pesticide risks to endangered and threatened species. We also held a stakeholder workshop in November 2013 to discuss and take comment on interim scientific approaches to address the National Academy of Science report recommendations.
The U.S. Environmental Protection Agency is consulting with NOAA Fisheries on the registration of 37 pesticide active ingredients pursuant litigation (see schedule).
As part of a court settlement with plaintiff Northwest Coalition for Alternatives to Pesticides (PDF, 8 pages), we agreed to complete biological opinions for the 37 active ingredients, with final deadlines specified for the different batches of pesticides.
Under Section 7 of the Endangered Species Act (ESA), federal agencies must consult with NOAA Fisheries on activities that may affect ESA-listed species. These inter-agency consultations are designed to help federal agencies in fulfilling their duty to ensure that their actions do not jeopardize the continued existence of a species, or destroy/adversely modify designated critical habitat. Below are links to NOAA Fisheries’ consultations or “Biological Opinions” on the Environmental Protection Agencies’ registration or registration review of pesticide active ingredients under the Federal Insecticide, Fungicide, and Rodenticide Act.
11. Chlorpyrifos, diazinon, and malathion (PDF 2,800 pages)
On June 30, 2022, NOAA Fisheries gave U.S. Environmental Protection Agency its final biological opinion relative to the potential effects of the pesticides chlorpyrifos, diazinon, and malathion on federally listed threatened or endangered species and their designated critical habitats.
NOAA Fisheries coordinated with EPA and the registrants for all three pesticides to modify the action in order to include additional species protections or “conservation measures.” After reviewing the current status of ESA-listed species, their environmental baseline within the action area, the effects of the proposed action (including the additional conservation measures) and cumulative effects, it is the National Marine Fisheries Services’ opinion that the Environmental Protection Agency’s action in the registration of the authorized uses, as will be specified by approved product labels, of all pesticide products containing diazinon, chlorpyrifos, and malathion, is not likely to jeopardize the continued existence of species or to destroy or destroy/adversely modify the designated critical habitat of those species.
10. Metolachlor and 1,3-Dichloropropene (PDF, 1,354 pages)
On June 30, 2021, NOAA Fisheries gave U.S. Environmental Protection Agency its final biological opinion relative to the potential effects of the pesticides metolachlor and 1,3-Dichloropropene on federally listed threatened or endangered Pacific salmon and steelhead and their designated critical habitat.
After reviewing the current status of salmonid species listed under the Endangered Species Act, their environmental baseline within the action area, the effects of the proposed action and cumulative effects, it is the National Marine Fisheries Services’ biological opinion that the Environmental Protection Agency’s action in the registration of the authorized uses, as specified by approved product labels, of all pesticide products containing metolachlor and 1,3-Dichloropropene is not likely to jeopardize the continued existence of twenty-eight Pacific salmon and steelhead species and is not likely to destroy or adversely modify the designated critical habitat of those twenty-eight listed species.
9. Bromoxynil and prometryn (PDF, 1,299 pages)
On June 30, 2021, NOAA Fisheries gave U.S. Environmental Protection Agency its final biological opinion relative to the potential effects of the pesticides bromoxynil and prometryn, on federally listed threatened or endangered Pacific salmon and steelhead and their designated critical habitat.
After reviewing the current status of salmonid species listed under the Endangered Species Act, their environmental baseline within the action area, the effects of the proposed action and cumulative effects, it is the National Marine Fisheries Services’ biological opinion that the Environmental Protection Agency’s action in the registration of the authorized uses, as specified by approved product labels, of all pesticide products containing bromoxynil and prometryn is not likely to jeopardize the continued existence of twenty-eight Pacific salmon and steelhead species and is not likely to destroy or adversely modify the designated critical habitat of those twenty-eight listed species.
8. Chlorpyrifos, diazinon, and malathion (PDF, 3,749 pages).
On December 29, 2017, NOAA Fisheries provided U.S. Environmental Protection Agency the final Biological Opinion evaluating the effects of the pesticides chlorpyrifos, diazinon, and malathion on federally-list species and designated critical habitats. This biological opinion replaces NOAA Fisheries 2008 biological opinion on salmonids and covers all listed species under NOAA Fisheries jurisdiction. This opinion represents the first collaboration of NOAA Fisheries, U.S. Environmental Protection Agency, U.S. Fish and Wildlife Service, and U.S. Department of Agriculture to implement new assessment approaches recommended by the National Academy of Sciences’ National Research Council to assess the risk of pesticides to endangered and threatened species (April 30, 2013).
U.S. Environmental Protection Agency determined that current application methods of chlorpyrifos, diazinon, and malathion are expected to produce aquatic concentrations of the three pesticides that are likely to cause harm to 77 federally-listed species and 50 designated critical habitats (https://www.epa.gov/endangered-species/biological-evaluation-chapters-chlorpyrifos-esa-assessment,https://www.epa.gov/endangered-species/biological-evaluation-chapters-diazinon-esa-assessment, https://www.epa.gov/endangered-species/biological-evaluation-chapters-malathion-esa-assessment). In sum, NOAA Fisheries concluded that chlorpyrifos, diazinon, and malathion are likely to jeopardize the continued many listed of 38 species (including several listed anadromous fish and Southern Resident killer whales) and adversely modify 37 designated critical habitats.
Diflubenzuron, fenbutatin oxide, and propargite (PDF, 833 pages).
On January 7, 2015, NOAA Fisheries gave U.S. Environmental Protection Agency its final biological opinion relative to the potential effects of the pesticides diflubenzuron, fenbutatin oxide, and propargite on federally listed threatened or endangered Pacific salmon and steelhead and their designated critical habitat.
NOAA Fisheries worked with the U.S. Environmental Protection Agency, U.S. Department of Agriculture, and the pesticide registrants on suggested changes to the pesticide labels before completing the biological opinion. We found that the proposed changes reduced risk but did not provide enough protections to avoid jeopardy or adverse modification of critical habitat. Therefore, the biological opinion recommends reasonable and prudent alternatives to protect Pacific salmon and steelhead. U.S. Environmental Protection Agency will consider the opinion and may propose additional mitigation measures during the registration review process for these pesticides.
Thiobencarb (PDF, 421 pages).
On July 2, 2012, NOAA Fisheries issued a final biological opinion concluding that the U.S. Environmental Protection Agency’s registration of the herbicide thiobencarb is not likely to jeopardize the continued existence of three listed Pacific salmonid evolutionarily significant units/distinct population segments or adversely modify their designated critical habitat.
Map of the Northwestern United States showing the distribution of ESA-listed Pacific salmonids.
We analyzed U.S. Environmental Protection Agency’s registration of thiobencarb based on its authorized use on rice. California is the only state within the range of listed Pacific salmonids that has approved the use of thiobencarb, and use is only approved for rice. As a result, this biological opinion focuses on three listed Pacific salmon evolutionarily significant units/distinct population segments located in California’s Central Valley where rice is grown. Re-initiation of this consultation will be necessary if thiobencarb is approved for use by other states with listed Pacific salmonids, or if thiobencarb use expands to any other parts of California within the range of listed Pacific salmonids.
Oryzalin, pendimethalin, and trifluralin (PDF, 1094 pages).
On May 31, 2012, NOAA Fisheries issued a final biological opinion addressing the effects of dinitroaniline herbicides on listed Pacific salmonids.
We concluded that oryzalin, pendimethalin, and trifluralin are likely to jeopardize the continued existence of some listed Pacific salmonids and adversely modify designated critical habitat of some listed salmonids.
Captan; chlorothalonil; 2,4-D; diuron; linuron; and triclopyr BEE (PDF, 1129 pages).
On June 30, 2011, NOAA Fisheries issued a final biological opinion addressing the effects of four herbicides (2,4-D; triclopyr BEE; diuron; linuron) and two fungicides (captan, chlorothalonil) on listed Pacfic salmonids. We concluded that:
Pesticide products containing chlorothalonil or diuron adversely modify designated critical habitat for some evolutionarily significant units/distinct population segments.
Pesticide products containing captan, linuron, or triclopyr BEE do not jeopardize the continued existence of any evolutionarily significant units/distinct population segments of listed Pacific salmonids or adversely modify designated critical habitat.
Azinphos-methyl, dimethoate, disulfoton, ethoprop, fenamiphos, methamidophos, methidathion, methyl parathion, naled, phorate, phosmet, bensulide (PDF, 1010 pages).
In August 2010, NOAA Fisheries concluded that pesticide products containing azinphos-methyl, disulfoton, fenamiphos, methamidophos, or methyl parathion are not likely to jeopardize the continuing existence of any listed Pacific salmon or destroy or adversely modify designated critical habitat.
We also concluded that the effects of products containing bensulide, dimethoate, ethoprop, methidathion, naled, phorate, or phosmet are likely to jeopardize the continued existence of some listed Pacific salmonids and to destroy or adversely modify designated habitat of some listed salmonids.
Carbaryl, carbofuran, and methomyl (PDF, 609 pages).
In April 2009, NOAA Fisheries concluded that pesticide products containing carbaryl, carbofuran, and methomyl are likely to jeopardize many populations of Endangered Species Act-listed Pacific salmonids and destroy or adversely modify their designated critical habitat. NOAA Fisheries released the following as part of its biological opinion:
Reasonable and Prudent Measures (PDF, 2 pages).
In 2010, the U.S. Environmental Protection Agency issued the following response to the 2010 opinion:
Chlorpyrifos, diazinon, and malathion (PDF, 484 pages).
These three chemicals are components of insecticides used in both agricultural and urban settings. The opinion concluded that these chemicals are likely to jeopardize 27 populations of salmon on the West Coast listed under the Endangered Species Act. However, this opinion was remanded on appeal in 2013 and is superseded by the NOAA Fisheries Opinion released in 2017.
In 2009, the U.S. Environmental Protection Agency issued an implementation plan in response to the opinion, which NOAA Fisheries then responded to:
In 2009, Dow Agrosciences LLC, et al., brought the following litigation against NOAA Fisheries:
Other Pesticide Consultations Activities
Pesticide Consultations Summary and Schedule
West Coast Salmon Recovery and Planning
Endangered Species Act Consultations
Endangered Species Conservation
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