Almost half of the world’s human population lives in coastal areas, and associated coastal development has significantly degraded or destroyed many coastal ecosystems. Burgeoning human populations and rising sea levels only further constrain the availability of habitat that coastal species depend on.

California’s 1,100 mile coast has more than 200 threatened, endangered or rare species living in coastal habitats. There are hundreds of coastal estuaries that provide critical rearing habitat for marine species, and are also important for recreation, water filtration, and carbon sequestration.

Only 10 percent of California’s historic coastal wetlands remain. Without intervention, we are at risk of losing 40 percent of our remaining coastal wetlands to sea level rise over the coming decades. Conservancy scientists are working to reverse these trends. 

Freshwater Systems

California is one of the most hydrologically altered landscapes in the world. As water becomes ever more scarce and… >>

Groundwater

In a normal year, groundwater accounts for 40 percent of California’s water supply. That number jumps to 60… >>

Surface Flows

Californians have fundamentally altered many of the state’s rivers and streams with dams, pipes, and diversions, and the… >>

Terrestrial Systems

In California, a day’s drive can take a visitor from record-setting desert heat to glaciated peaks to temperate… >>

Wildlands

Nearly half of California is protected in some land status that prevents most kinds of intensive human land… >>

Harvested Landscapes

A third of California is privately-owned forestland, woodland or grassland. From redwood forests on the north coast to… >>

Cultivated Landscapes

California is the leading agricultural state in the country and it’s agriculture generates more than $45 billion annually.… >>

Urban Areas and Infrastructure

With California’s population on track to reach 50 million people, the demand for energy, water, and land will… >>

Fisheries

Wild capture fisheries supply food and jobs for hundreds of millions of people across the globe. Yet an… >>

Coastal Conservation

Almost half of the world’s human population lives in coastal areas, and associated coastal development has significantly degraded… >>

Science in Action

Terrestrial | Marine | Planning

TNC and the U.S. Navy

How can we protect natural resource and coastal military assets from sea level rise?

Freshwater | Terrestrial | Science

Rewilding the San Joaquin Valley

40 years of science sets the course for the largest recovery of species in U.S. history

2022 | Freshwater | Terrestrial | Marine | Planning | Technology | Science | Publications & Reports

Prioritizing actions: spatial action maps for conservation

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…


2022 | Marine | Planning | Science | Publications & Reports

Restoring shellfish reefs: Global guidelines for practitioners and scientists

James A. Fitzsimons, Simon Branigan, Chris L. Gillies, Robert D. Brumbaugh, Jun Cheng, Bryan M. DeAngelis, Laura Geselbracht, Boze Hancock, Andrew Jeffs, Tein McDonald, Ian M.McLeod, Bernadette Pogoda, Seth J. Theuerkauf, Marine Thomas, Stephanie Westby, Philine S.E. zu Ermgassen

Widespread global declines in shellfish reefs have led to growing interest in their restoration and protection. With restoration projects now occurring on four continents and in at least seven countries, this project developed global restoration guidelines for these ecosystems, developed based on experience over the…


2022 | Marine | Planning | Science | Publications & Reports

The benefits of bivalve reef restoration: A global synthesis of underrepresented species

Philine S. E. zu Ermgassen, Ruth H. Thurstan, Jorge Corrales, Heidi Alleway, Alvar Carranza, Norbert Dankers, Bryan DeAngelis, Boze Hancock, Flora Kent, Ian McLeod, Bernadette Pogoda, Qing Liu, William G. Sanderson

Bivalve habitat restoration is growing in geographic extent and scale globally. Stakeholders and funders are increasingly drawn to shellfish restoration for the many ecosystem services these habitats provide. Ecosystem services, however, remain largely unquantified or even undescribed for the majority of species targeted for restoration.…


2022 | Marine | Planning | Science | Publications & Reports

Estimating and Applying Fish and Invertebrate Density and Production Enhancement from Seagrass, Salt Marsh Edge, and Oyster Reef Nursery Habitats in the Gulf of Mexico

Philine S. E. zu Ermgassen, Bryan DeAngelis, , Jonathan R. Gair, Sophus zu Ermgassen, Ronald Baker, Andre Daniels, Timothy C. MacDonald, Kara Meckley, Sean Powers, Marta Ribera, Lawrence P. Rozas & Jonathan H. Grabowski

Seagrasses, oyster reefs, and salt marshes are critical coastal habitats that support high densities of juvenile fish and invertebrates. Yet which species are enhanced through these nursery habitats, and to what degree, remains largely unquantified. Quantitative estimates of production enhancement within specific embayments can be…


2022 | Marine | Planning | Science | Publications & Reports

Social Factors Key to Landscape-Scale Coastal Restoration: Lessons Learned from Three U.S. Case Studies

Bryan M. DeAngelis, Ariana E. Sutton-Grier, Allison Colden, Katie K. Arkema, Christopher J. Baillie, Richard O. Bennett, Jeff Benoit, Seth Blitch, Anthony Chatwin, Alyssa Dausman, Rachel K. Gittman, Holly S. Greening, Jessica R. Henkel, Rachel Houge, Ron Howard, A. Randall Hughes, Jeremy Lowe, StevenB. Scyphers, Edward T. Sherwood, Stephanie Westby, Jonathan H. Grabowski

This study examined three case studies involving large-scale and long-term restoration efforts including the seagrass restoration effort in Tampa Bay, Florida, the oyster restoration effort in the Chesapeake Bay in Maryland and Virginia, and the tidal marsh restoration effort in San Francisco Bay, California.The studyfocused…


2022 | Marine | Planning | Science | Publications & Reports

Restoration Guidelines for Shellfish Reefs

J. Fitzsimons, S. Branigan, R.D. Brumbaugh , T. McDonald, and zu Ermgassen, P.S.E. (eds), Bryan M. DeAngelis, chapter author

The purpose of this guide is to provide guidance in decision-making for establishing shellfish reef restoration projects and examples of different approaches undertaken byexperienced practitioners in a variety of geographic, environmental and social settings. This publication is intended to provide foundational information to serve as…


2022 | Freshwater | Terrestrial | Publications & Reports

Restoration richness tipping point meta-analysis: finding the sweet spot

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…


2022 | Terrestrial | Planning | Technology | Science | Publications & Reports

A framework to select strategies for conserving and restoring habitat connectivity in complex landscapes

D. Richard Cameron, Carrie A. Schloss, David M. Theobald, Scott A. Morrison

Protecting or restoring habitat connectivity in landscapes undergoing rapid environmental change requires multiple conservation and restoration strategies. These strategies have different risk profiles, costs, and require various types of expertise to conduct. This diversity in landscape context and strategic approach requires more nuance than traditional…


2022 | Terrestrial | Planning | Science | Data

The Resilient Connected Network in California

Carrie Schloss, Dick Cameron, Elizabeth McGovern

As declines in biodiversity are further exacerbated by changing climate conditions, it is critical to ensure that plants and animals are resilient to the effects of climate change.  This means protecting the places plants and animals are already thriving, important movement routes, and ensuring that…


2022 | Terrestrial | Planning | Technology | Science | Publications & Reports

The influence of model frameworks in spatial planning of regional climate-adaptive connectivity for conservation planning

Hyeyeong Choe, Annika T.H. Keeley, D. Richard Cameron, Melanie Gogol-Prokurat, Lee Hannah, Patrick R. Roehrdanz, Carrie A. Schloss, James H. Thorne

Planning for connectivity conservation often relies on modeled movement routes. However, these pathways can be sensitive to the conservation objective, modeling approach, analysis tool, and assumptions. The authors compared four different approaches to planning for connectivity for climate adaptation in California.  Three or more models…


2022 | Freshwater | Terrestrial | Marine | Planning | Technology | Science | Maps & Webmaps

The Mitigation Wizard

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…


2022 | Terrestrial | Planning | Science | Maps & Webmaps

Conserving a Global Biodiversity Hotspot, 30x30: A Path to a Resilient Future

Carrie Schloss, Dick Cameron, Charlotte Stanley, Megan Webb

In October 2020, Governor Newsom signed an executive order committing to protect 30% of California by 2030. This could put California on a trajectory to stem the biodiversity crisis. But, where this touches down matters. This storymap makes the case for conducting a planning process…


2022 | Terrestrial | Planning | Technology | Science | Publications & Reports

“No-regrets” pathways for navigating climate change: planning for connectivity with land use, topography, and climate

Carrie A. Schloss, D. Richard Cameron, Brad H. McRae, David M. Theobald, and Aaron Jones

Plant and animal species are already shifting their ranges in response to a changing climate. Maintaining connectivity between present habitat and suitable habitat in the future will become increasingly important to ensure lasting protection for biodiversity. Connectivity that facilitates climate adaptation requires pathways with "stepping…


2022 | Marine | Planning | Science | Publications & Reports

Kelp Restoration Guidebook: Lessons Learned from Kelp Restoration Projects Around the World

Aaron M. Eger (University of New South Wales), Cayne Layton (University of Tasmania), Tristin A. McHugh (TNC), Mary Gleason, and Norah Eddy (TNC)

Kelp forests around the world are experiencing significant declines due to a variety of factors, driving the need for more active kelp restoration efforts. The science and practice of kelp forest restoration is still in its infancy and there remains a wealth of knowledge to…


2022 | Freshwater | Planning | Science | Publications & Reports

A Machine Learning Approach to Predict Groundwater Levels in California Reveals Ecosystems at Risk

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…


2022 | Freshwater | Planning | Science | Maps & Webmaps

SAGE: Shallow Groundwater Estimation Tool

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…


2022 | Freshwater | Planning | Science | Publications & Reports

Groundwater dependence of riparian woodlands and the disrupting effect of anthropogenically altered streamflow

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…


2022 | Freshwater | Terrestrial | Technology | Science | Publications & Reports

Quantity and fate of synthetic microfiber emissions from apparel washing in California and strategies for their reduction

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…


2022 | Marine | Technology | Science | Publications & Reports

Reducing the Risk of Mortality to Whales

Jessica Morten, Ryan Freedman, Jeffrey D. Adams, Jono Wilson, Aliya Rubinstein, Sean Hastings

The great whales, including, blue, humpback, and fin whales are threatened by collisions with ocean going vessels. Global shipping traffic is projected to increase up to 12-fold in coming decades. Slowing vessels down reduces the risk of whale collisions and mortality. Here, the authors examined…


2022 | Marine | Technology | Science | Publications & Reports

Lost Fishing Gear is a Key Contributor to Ocean Plastic Pollution

Brandon Kuczenski, Camila Vargas Poulsen, Eric L. Gilman, Michael Musyl, Roland Geyer, Jono Wilson

More than 4.5 million fishing vessels ply ocean waters each year, setting countless nets, traps, hooks and lines. Much of this fishing gear is made of plastic components and a significant fraction of it is lost in the ocean each year, causing irreparable harm to…