California is one of the most hydrologically altered landscapes in the world. As water becomes ever more scarce and the human population continues to grow, that vast engineered system strains to meet the needs of people let alone the needs of nature.
Water rights allocations far exceed actual surface water supply, and millions of wells tap groundwater to meet the increasing demands of farms and communities. As groundwater reservoirs are depleted they can in turn reduce surface flows – exacerbating a vicious cycle in which people and nature both lose. Rivers, wetlands and groundwater-dependent ecosystems are caught in this struggle for an increasingly limited resource. Nearly half of California’s roughly 4,000 freshwater species are considered vulnerable to extinction. Of the taxa that are found nowhere but California – our endemic freshwater biodiversity – 90 percent are at risk.
But there is hope. While it is impossible to return natural flows to most of California’s rivers and streams, we can – through science, technology, and innovative market tools – endeavor to deliver water when and where nature needs it most.
In a normal year, groundwater accounts for 40 percent of California’s water supply. That number jumps to 60… >>
Californians have fundamentally altered many of the state’s rivers and streams with dams, pipes, and diversions, and the… >>
Heather Tallis, Joe Fargione, Edward Game, Rob McDonald, Leandro Baumgarten, Nirmal Bhagabati, Rane Cortez, Bronson Griscom, Jonathan Higgins, Christina M. Kennedy, Joe Kiesecker, Timm Kroeger, Trina Leberer, Jennifer McGowan, Lisa Mandle, Yuta J. Masuda, Scott Morrison, Sally Palmer, Rebecca Shirer, Priya Shyamsundar, Nicholas H.Wolff, and Hugh P. Possingham
Spatial analysis is a powerful tool in conservation planning. Yet it is often under-deployed as a means of elucidating which conservation actions may deliver the highest return on investment. This paper presents a framework for “spatial action mapping” and discusses how it can improve conservation…
Christopher J. Lortie, Maria Florencia Miguel, Alessandro Filazzola, Harry Scott Butterfield
Climate change, drought, and water scarcity are driving major land transformations in dryland ecosystems globally. Historically these ecosystems have been disproportionately degraded due to widespread agricultural conversion. Because of these pressures, there are significant opportunities for rewilding and restoration of these dryland ecosystems. This global…
Carrie Schloss, Liz O’Donoghue, Dan Rademacher, Patric Huber, Jodi McGraw, Kim Becerril, Janine Knapp
Every year, infrastructure agencies and developers spend hundreds of millions of dollars to mitigate for impacts to sensitive species and habitats. These mitigation sites are often piecemeal projects, which can result in islands of mitigation. Regional advance mitigation programs seek to change this paradigm so…
Melissa M. Rohde, Tanushree Biswas, Ian W. Housman, Leah S. Campbell, Kirk R. Klausmeyer, Jeanette Howard
Groundwater dependent ecosystems (GDEs) are increasingly threatened worldwide, but the shallow groundwater resources that they are reliant upon are seldom monitored. In this study, the researchers used satellite-based remote sensing, climate data, and machine learning to predict groundwater levels over a 35 year period (1985…
Melissa M. Rohde, Tanushree Biswas, Ian W. Housman, Leah S. Campbell, Kirk R. Klausmeyer, Jeanette Howard
Groundwater dependent ecosystems (GDEs) are critical habitats throughout California that rely on shallow groundwater. Unfortunately, only a small subset of wells provide monitoring data for shallow groundwater. This tool, developed for a publication in Frontiers in Earth Science, uses satellite data and machine learning tools to…
Melissa M. Rohde, John C. Stella, Dar A. Roberts, Michael Bliss Singer
This study combines satellite, groundwater, and streamflow data over a 5 year period (2015-2020) to understand the impacts of groundwater depth and streamflow alteration on groundwater-dependent vegetation across California. The study shows that deeper groundwater levels resulted in poor vegetation health, but that current water management…
Roland Geyer, Jenna Gavigan, Alexis M. Jackson, Vienna R. Saccomanno, Sangwon Suh, Mary G. Gleason
Synthetic microfibers are the most prevalent type of microplastic and apparel washing is a major source of microfiber pollution. Using California as a case study to estimate the magnitude of microfiber emissions and evaluate mitigation approaches, the authors estimate that in 2019 over 4,850,000 pounds (2.2…
Gabriel Rossi, Darren Mierau, Jennifer Carah
A simple stream depth measurement at the deepest part of a riffle crest in a river or stream provides an easy-to-measure and inexpensive metric for ecological researech, environmental flow management, and habitat assessment. This paper describes measurement methods, as well as ways to use riffle measurements…
Kate Longley-Wood, Mary Engels , Kevin D. Lafferty, John P. McLaughlin, Alex Wegmann
Native forests on tropical islands have been displaced by non-native species, leading to calls for their transformation. Simultaneously, there is increasing recognition that tropical forests can help sequester carbon that would otherwise enter the atmosphere. At Palmyra Atoll, efforts are underway to transform the rainforest…
Brynn Pewtherer, Scott Morrison
The Nature Conservancy deploys science to help overcome major challenges facing people and nature. In today’s fast-paced world, turning threats to nature into opportunities for conservation requires agility. The Conservation Science Catalyst Fund enables our science team to mobilize quickly — and produce the information…
Case study by: K.D. Holl, G.H. Golet
Advancing conservation requires understanding the constraints imposed on natural systems by human societies. This understanding typically comes from engagement with local stakeholders, as opposed to from scholastic training. A recent textbook on restoration ecology by Karen Holl seeks to alleviate this problem by providing real-world…
O.J. Robinson, V. Ruiz-Gutierrez, M.D. Reynolds, G.H. Golet, M. Strimas-Mackey and D. Fink
Information on species’ habitat associations and distributions, across wide spatial and temporal scales, is fundamental for guiding conservation. Yet these data are often in short supply. In recent years citizen science data, such as that derived from eBird, has increasingly become available to fill…
Kelsey Jessup, Sophie S. Parker, John M. Randall, Brian S. Cohen, Rowan Roderick-Jones, Shona Ganguly, Jill Sourial
This paper presents results from Planting Stormwater Solutions, part of TNC’s Urban Conservation work in Los Angeles. The authors develop a methodology to prioritize siting of vegetated nature-based solutions for stormwater capture so that these projects maximize benefits to biological diversity, social and public…
Environmental Science Associates (ESA) for The Nature Conservancy and Naval Base Ventura County
Charlotte Stanley, Alyssa Mann, Walter Heady
The United States operates thousands of military installations in the U.S. and worldwide, worth about $1.2 trillion. These facilities are where personnel train and test weaponry, with the specific aim of ensuring the nation’s security. With climate change, coastal installations are now being impacted by rising sea levels, erosion and…
Walter Heady, Alyssa Mann, Stacey Solie, Bob Battalio, James Jackson, Kendall Lousen, and Bob Barnes
The U.S. Congress and the Department of Defense (DoD) have determined that climate change is a threat to national security and have required military installations to develop plans to improve the climate resilience of both military installations and key supporting civilian infrastructure. This report, co-authored…
Alyssa Mann, Walter Heady, Charlotte Stanley
TNC and the United States Navy partnered together to prepare for the impacts of climate change on Naval Base Ventura County (NBVC), Point Mugu in California. NBVC is a critical and strategic asset of the U.S. Navy. It is also home to Mugu Lagoon, the…
Christopher Dillis, Van Butsic, Jennifer Carah, Samuel Zipper, Theodore Grantham
Water management practices for cannabis farming in California are not well understood. This study examined permit reporting data and found that the vast majority (>75%) of permitted cannabis farms use groundwater wells to source water, with many wells located outside regulated groundwater basins. Groundwater pumping…
Barton H. Thompson, Jr., Melissa M. Rohde, Jeanette K. Howard, Sandi Matsumoto
In 2014, California’s landmark Sustainable Groundwater Management Act (SGMA) promised comprehensive management of California’s groundwater. This report, Mind the Gaps: The Case for Truly Comprehensive Sustainable Groundwater Management, based on joint analysis by Water in the West at Stanford University and The Nature Conservancy, finds…
Christopher Dillis, Eric Biber, Hekia Bodwitch, Van Butsic, Jennifer Carah, Phoebe Parker-Shames, Michael Polson, and Theodore Grantham
This study used permitting and GIS data to explore geographic characteristics of legal cannabis farms in California. The study found two divergent paths of development - one characterized by numerous, smaller farms in rugged, tree-covered landscapes in historical cannabis producing regions (Humboldt, Mendocino, Trinity counties),…