Improving Infrastructure for Wildlife

Social Science Research Network (SSRN) | February 25th, 2021

In Washington v. United States, 584 U.S. ___ (2018), the Supreme Court required Washington State to improve fish passage through almost 1,000 culverts originally built to

In Washington v. United States, 584 U.S. ___ (2018), the Supreme Court required Washington State to improve fish passage through almost 1,000 culverts originally built to allow streamflow under roads and highways. The case highlighted conflicts between wildlife needs and infrastructure development. Fish passage through outdated or ill-designed culverts is only a small facet of the larger problem of outdated wildlife infrastructure. Impinged migration corridors for ungulates, turtles, and other mobile taxa; levees disconnecting floodplains from rivers; poor water temperature controls on dams; and eroding ecological productivity accompanying aging of reservoirs exemplify the types of challenges to wildlife created by contemporary infrastructure.

Improving the Health of California’s Headwater Forests

Public Policy Institute of California (PPIC) | September 18th, 2017

California’s headwater forests are not thriving under current management practices, and changes are needed to make them more resilient to periodic drought and long-term

California’s headwater forests are not thriving under current management practices, and changes are needed to make them more resilient to periodic drought and long-term climate change. More active management of these lands is needed to improve forest health, reduce the risk of major wildfires and pest infestations, and maintain the flow of benefits provided by this critical natural infrastructure. Decades of fire suppression, an emphasis on short-term management priorities, weather extremes, and a warming climate have set the stage for the decline in forest resilience. Two-thirds of the state’s surface water supply originates in these mountainous forests. California stands to lose timber production, wildlife habitat, recreational opportunities, and water supply if this vital natural infrastructure continues to decline. Management options exist—prescribed fire, managed wildfire, mechanical thinning, and forest pest treatments—that can help rebuild resilience in these forests and prepare them for a challenging future.

In situ allelopathic expression by the invasive amphibious plant, Ludwigia hexapetala (water primrose) across habitat types, seasons, and salinities

Biological Invasions (Springer Link) | August 17th, 2024

Broad infestations of invasive, non-native vegetation have transformed wetlands around the world. Ludwigia hexapetala is a widespread, amphibious invasive plant with a cr

Broad infestations of invasive, non-native vegetation have transformed wetlands around the world. Ludwigia hexapetala is a widespread, amphibious invasive plant with a creeping growth habit in open water and an erect growth habit in terrestrial habitats. In the upper San Francisco Estuary of California, L. hexapetala is increasingly terrestrializing into marshes and this expansion may be facilitated by allelopathy. We conducted the first field-based study on L. hexapetala allelopathy to determine whether (1) three allelochemicals known to be exuded by L. hexapetala are expressed in situ, (2) the allelochemicals are detectable in leaves, soil, and water, and (3) allelopathic expression varies by season, salinity, and growth habit (open water “patch” vs. terrestrial marsh “interface” locations). Water, soil, and L. hexapetala leaves were collected in two freshwater sites and two oligohaline sites in the upper San Francisco Estuary in summer 2021, fall 2021, and spring 2022. Myricitrin and quercitrin, known allelochemicals, and salipurposid, a newly identified polyphenol, were detected in water, soil, and leaves. There were significant differences in allelochemical concentrations under fresh versus oligohaline conditions in water and soil, but not leaves. All three allelochemicals generally had higher concentrations in patch versus interface locations, suggesting that L. hexapetala allelopathy plays a greater competitive role in open water than terrestrial habitats. Leaf concentrations of each allelochemical varied seasonally; however, both myricitrin and salipurposid had heightened concentrations in spring. These results suggest that herbicide application in early spring may be most effective in controlling L. hexapetala terrestrialization from open water to marshes.

Inadequate Government-Led Water-Quality Monitoring Hinders Improvement Efforts in the Salton Sea

University of California, Los Angeles (UCLA) | September 4th, 2025

California’s largest inland body of water, the Salton Sea, has faced severe environmental degradation, leaving lasting impacts on surrounding desert communities. Situat

California’s largest inland body of water, the Salton Sea, has faced severe environmental degradation, leaving lasting impacts on surrounding desert communities. Situated between Riverside and Imperial counties, the lake has endured the effects of jurisdictional challenges, climate change, and unsustainable agricultural practices that have exacerbated nutrient pollution to levels surpassing those found in most lakes across the United States. Data collected over 16 years of quarterly government sampling and 12 months of high-frequency sampling—conducted collaboratively by local communities and the University of California, Los Angeles—consistently reveal high concentrations of nitrates and dangerously low oxygen levels in the water column. These nutrient-rich conditions create an environment conducive to hydrogen sulfide emissions, which persist around the Salton Sea at levels that exceed health standards and raise ongoing concerns within the community. The State of California and the federal government are contractually obligated to restore the Salton Sea. To address the water-quality issues and their consequences, we recommend a combination of environmental and economic remediation efforts aimed at improving the Salton Sea’s ecosystem and its resulting impact on nearby communities.

Incentive-based Instruments for Freshwater Management

Pacific Institute | December 1st, 2015

This new synthesis report from the Pacific Institute and the Foundation Center provides a review of existing evidence about the use of incentive-based instruments worldwi

This new synthesis report from the Pacific Institute and the Foundation Center provides a review of existing evidence about the use of incentive-based instruments worldwide. Based on case studies, evaluations, journal articles, and white papers, the authors provide a detailed review of three incentive-based instruments: water trading, payment for ecosystem services, and water quality trading. The report and interactive tool highlight the importance of finding the right fit between a community’s water goals and the water management tool(s) it might choose and, perhaps most importantly, characterize the conditions required for their effective implementation. Originally commissioned by The Rockefeller Foundation, all of the results from this project: the synthesis report, interactive tool, and digital collection are freely available for funders, practitioners, and researchers to use, contribute to, and build on in their work.

Inclusion of Pesticide Transformation Products Is Key to Estimating Pesticide Exposures and Effects in Small U.S. Streams

American Chemical Society (ACS) | March 10th, 2021

Improved analytical methods can quantify hundreds of pesticide transformation products (TPs), but understanding of TP occurrence and potential toxicity in aquatic ecosyst

Improved analytical methods can quantify hundreds of pesticide transformation products (TPs), but understanding of TP occurrence and potential toxicity in aquatic ecosystems remains limited. We quantified 108 parent pesticides and 116 TPs in more than 3 700 samples from 442 small streams in mostly urban basins across five major regions of the United States. TPs were detected nearly as frequently as parents (90 and 95% of streams, respectively); 102 TPs were detected at least once and 28 were detected in >20% samples in at least one region—TPs of 9 herbicides, 2 fungicides (chlorothalonil and thiophanate-methyl), and 1 insecticide (fipronil) were the most frequently detected. TPs occurred commonly during baseflow conditions, indicating chronic environmental TP exposures to aquatic organisms and the likely importance of groundwater as a TP source. Hazard quotients based on acute aquatic-life benchmarks for invertebrates and nonvascular plants and vertebrate-centric molecular endpoints (sublethal effects) quantify the range of the potential contribution of TPs to environmental risk and highlight several TP exposure–response data gaps. A precautionary approach using equimolar substitution of parent benchmarks or endpoints for missing TP benchmarks indicates that potential aquatic effects of pesticide TPs could be underestimated by an order of magnitude or more.

Increasing elevation of fire in the Sierra Nevada and implications for forest change

Ecological Society of America (ESA) | July 23rd, 2015

Fire in high‐elevation forest ecosystems can have severe impacts on forest structure, function and biodiversity. Using a 105‐year data set, we found increasing elevat

Fire in high‐elevation forest ecosystems can have severe impacts on forest structure, function and biodiversity. Using a 105‐year data set, we found increasing elevation extent of fires in the Sierra Nevada, and pose five hypotheses to explain this pattern. Beyond the recognized pattern of increasing fire frequency in the Sierra Nevada since the late 20th century, we find that the upper elevation extent of those fires has also been increasing. Factors such as fire season climate and fuel build up are recognized potential drivers of changes in fire regimes. Patterns of warming climate and increasing stand density are consistent with both the direction and magnitude of increasing elevation of wildfire. Reduction in high elevation wildfire suppression and increasing ignition frequencies may also contribute to the observed pattern. Historical biases in fire reporting are recognized, but not likely to explain the observed patterns. The four plausible mechanistic hypotheses (changes in fire management, climate, fuels, ignitions) are not mutually exclusive, and likely have synergistic interactions that may explain the observed changes. Irrespective of mechanism, the observed pattern of increasing occurrence of fire in these subalpine forests may have significant impacts on their resilience to changing climatic conditions.

Independent Panel Review of the Bay Delta Conservation Plan prepared for The Nature Conservancy and American Rivers

Nature Conservancy | September 19th, 2013

Two non-­governmental organizations, The Nature Conservancy (TNC) and American Rivers (AR), are evaluating their options for engagement with the Bay Delta Conservation P

Two non-­governmental organizations, The Nature Conservancy (TNC) and American Rivers (AR), are evaluating their options for engagement with the Bay Delta Conservation Plan (BDCP). If approved, the Plan would become a Habitat Conservation Plan (HCP) under the federal Endangered Species Act and a Natural Communities Conservation Plan (NCCP) under California law. The purpose of the Plan is to allow for construction of new water diversion facilities in the Sacramento-­San Joaquin Delta while also protecting aquatic and terrestrial species that may be adversely affected by the project and accompanying changes in the State Water Project (SWP) and Central Valley Project (CVP) operations. The Plan also includes habitat restoration and a commitment to assist in the conservation and recovery of species that are listed for protection under the federal and state Endangered Species Acts. With financial support from the S.D. Bechtel, Jr. Foundation, Saracino and Mount, LLC, convened an independent panel of experts, with technical support from NewFields, Inc., to evaluate portions of the Plan. The panel, working jointly with TNC and AR, developed a series of technical and legal questions about the Plan. This report provides answers to these questions, along with limited recommendations on how to improve BDCP. To simplify analysis, this review focuses on conditions for federally listed fishes during the Early Long Term (ELT), a decade after a permit would be issued (approximately year 2025). These are described in detail in the BDCP Effects Analysis and accompanying Environmental Impact Statement/Environmental Impact Report. We compared the performance of three different scenarios: a No Action Alternative (NAA) where no new North Delta diversion facility is constructed, a High Outflow Scenario (HOS) where the facilities are operated in a way that allows for occasional high spring and fall outflows, and a Low Outflow Scenario (LOS) with lower spring and fall outflows. The review also emphasizes in-­Delta and Sacramento River watershed conditions during the ELT, with less attention to San Joaquin River conditions and fishes. Although multiple data sources were used in this analysis, most hydrologic data came from CALSIM simulations conducted by BDCP consultants. The Panel strongly cautions about the conclusions drawn from these simulations. Flow simulations have three compounding uncertainties that can lead to significant error: (1) uncertainty in system understanding and future conditions, (2) model uncertainties (particularly the relationships between 1-­, 2-­, and 3-­dimensional models), and (3) behavioral/regulatory uncertainty where the models cannot capture the scope of human behavior in operating the projects under various conditions. These uncertainties, which are not described in BDCP documents well, makes all of our conclusions contingent on the projects actually being operated as simulated.

Independent Review Panel (IRP) Report for the 2014 Long-Term Operations Biological Opinions (LOBO) Annual Science Review

Delta Stewardship Council (Delta Council) | December 1st, 2014

Independent Review Panel (IRP) Report for the 2015 Long-Term Operations Biological Opinions (LOBO) Annual Science Review

Delta Stewardship Council (Delta Council) | December 1st, 2015

This report presents findings and opinions of the Independent Review Panel (IRP) assembled by the Delta Science Program to inform the National Marine Fisheries Service (N

This report presents findings and opinions of the Independent Review Panel (IRP) assembled by the Delta Science Program to inform the National Marine Fisheries Service (NMFS) and the U.S. Fish & Wildlife Service (USFWS) as to the efficacy of water operations and certain regulatory actions prescribed by their respective Long-term Operations Biological Opinions’ (LOBO) Reasonable and Prudent Alternative Actions (RPAs) as applied from October 1, 2014 through September 30, 2015 (Water Year 2015).  This year’s annual review focused primarily on: (1) Shasta Reservoir and Sacramento River temperature monitoring, modeling, and management, (2) the River Assessment for Forecasting Temperature (RAFT) decision support tool (model), (3) an Enhanced Particle Tracking Model (E-PTM), and (4) a USFWS report on past, present, and future approaches to incidental take of Delta Smelt.  After reviewing a required set of written documents (Appendix 1), the IRP convened at a public workshop in Sacramento, CA on 5-6 November 2015. The first day of the 2-day workshop included agency presentations and provided a forum for the IRP to interact and consider information presented on water operations, temperature modeling, monitoring and RPA Actions as implemented in yet another critically dry 2015 water year. On the second day, the IRP deliberated in a private session beginning at 9:00 a.m. in order to prepare and present their initial findings at the public workshop at 2:00 p.m., after which there was an opportunity for agency representatives, members of the public, and the IRP members to comment and otherwise exchange impressions and information. Subsequent IRP communication and deliberations were conducted via email and conference calls in the course of drafting this final report. Click here for federal agency response letter