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. 

Science in Action

Marine | Technology | Science

Closing the Abalone Data Gap

Can putting technology in the hands of citizen scientists transform how abalone are managed?

Marine | Planning | Science

Saving Tomorrow’s Coast

Can California protect its iconic coastline as sea levels rise?

2018 | Marine | Planning | Technology | Science | Blogs

Managing Fisheries in the Face of Climate Change

Jono Wilson

The author discusses a need for a new paradigm in fisheries management to address the challenges of a changing climate.  See related publication by the author and colleagues in Conservation Letters.


2018 | Marine | Science | Publications & Reports

CA Rock Crab Fishery Management

Sean P. Fitzgerald, Jono R. Wilson , Hunter S. Lenihan

Despite the economic value of California fisheries, many lack information needed to determine if fishing is occurring at a sustainable level. The Southern California Rock Crab fishery in the Santa Barbara Channel is one such data-limited fishery that is currently managed through a state-wide size…


2018 | Freshwater | Terrestrial | Marine | Planning | Science | Publications & Reports

Conserving California's Coastal Habitats: A Legacy and a Future with Sea Level Rise

Walter N. Heady, Brian S. Cohen, Mary G. Gleason, Joshua N. Morris, Sarah G. Newkirk, Kirk R. Klausmeyer, Hilary R. Walecka, Elizabeth Gagneron

Sea level rise presents a new challenge to coastal conservation. The authors quantified and mapped the vulnerability of habitats, imperiled species, and conservation lands to sea level rise throughout the entire California coast, where high biodiversity, high endemism, and 26.5 million people coincide. Combining habitat…


2018 | Freshwater | Terrestrial | Marine | Planning | Science | Publications & Reports

Improving multi-objective ecological flow management with flexible priorities and turn-taking: a case study from the Sacramento River and Sacramento-San Joaquin Delta

Alexander C.A.D., F. Poulsen, D.C.E. Robinson, B.O. Ma , R.A. Luster

Management of the Sacramento River and Sacramento–San Joaquin Delta is one of California’s greatest challenges, requiring trade-offs between valued components that serve a multiplicity of conflicting purposes. This paper demonstrates an improved method for multiple-objective allocation of water based on a “turn-taking” optimization model. The…


2017 | Marine | Technology | Science | Video

Aquaculture by Design, Tomales Bay

Serena Lomonico, Robert Jones, Torrey Johnson, Sarah Newkirk, Sarah Lummis, Kirk Klausmeyer, John Finger, Terry Sawyer, Richard James

Aquaculture is becoming an increasingly important global food source. With this growth comes urgent, unanswered questions about the interactions of aquaculture operations—both positive and negative—and ecosystems. This video describes a collaboration between the Conservancy, the University of California, Santa Cruz, and Hog Island Oyster Company aimed at…


2016 | Marine | Technology | Science | Video

Sustainable Management of Abalone Fishery in California

The Nature Conservancy, Jono Wilson

California fisheries, like the red abalone fishery, are facing increasing environmental variation and uncertainty due to climate change, complicating the sustainable management of commercial and recreational fisheries and threatening the resilience of fishing communities. To better manage these resources, better data is needed. In this video,…


2016 | Marine | Publications & Reports

Marine and Coastal Impacts of Ocean Desalination in California

Szeptycki, L., E. Hartge, N. Ajami, A. Erickson, W. N. Heady, L. LaFeir, B. Meister, L. Verdone, J.R. Koseff

The drought in California rekindled interest in ocean desalination as a new and reliable water supply option; yet desalination is expensive, energy intensive, potentially emits greenhouse gases, and has adverse impacts on coastal and marine ecosystems. This report is a synthesis of an Uncommon…


2015 | Freshwater | Marine | Publications & Reports

Assessing California’s bar-built estuaries using the California Rapid Assessment Method

Walter Heady, Ross P. Clark, Kevin O’Connor, Cara Clark, Charles Endris, Sierra Ryan, Sara Stoner-Duncan

Connecting marine, freshwater and terrestrial ecosystems, bar-built estuaries are complex and dynamic coastal confluences that provide a great diversity of habitat and ecosystem services. The wetland habitats of bar-built estuaries are threatened by development, pollution, and climate related changes including diminished streamflows and sea…


2015 | Marine | Planning | Maps & Webmaps

Coastal Resilience Monterey webmap

Brian Cohen

The Coastal Resilience Network supports a community of practitioners who are applying nature-based solutions to coastal hazard and climate adaptation issues. As a member of this Network, the Conservancy is working with scientists, geomorphologists, urban and environmental economists, regional conservation partners, and local stakeholders…


2015 | Marine | Planning | Maps & Webmaps

Coastal Resilience Ventura Web Map

Brian Cohen

As a member of the Coastal Resilience Network, the Conservancy is leading Coastal Resilience Ventura. Coast Resilience Ventura is a partnership that provides science and decision-support tools to help conservation practitioners, planners and policymakers address the impact of climate change. Through this effort, the…


2015 | Freshwater | Marine | Publications & Reports

Aligning Natural Resource Conservation and Flood Hazard Mitigation in California

Juliano Calil, Michael W. Beck, Mary Gleason, Matthew Merrifield, Kirk Klausmeyer, Sarah Newkirk

The U.S. National Flood Insurance Program has paid out more than $38 billion in claims since its inception in 1968, more than a third of which has gone to the 1% of policies that experienced multiple, repetitive losses. During the same period, the loss of…


2015 | Freshwater | Marine | Publications & Reports

Climate mediates hypoxic stress on fish diversity and nursery function at the land–sea interface

Brent B. Hughes, Matthew D. Levey, Monique C. Fountain, Aaron B. Carlisle, Francisco P. Chavez, Mary G. Gleason

This comprehensive study of a major California estuary documents the links between nutrient runoff from coastal land use, the health of the estuary as a nursery for young fish, and the abundance of fish in an offshore commercial fishery. The researchers assembled long-term data sets…


2014 | Freshwater | Marine | Planning | Publications & Reports

An Inventory and Classification of U.S. West Coast Estuaries

Walter N. Heady, Kevin O'Connor, Jennifer Kassakian , Kate Doiron, Charles Endris, Daniel Hudgens, Ross P. Clark , Jena Carter , Mary G. Gleason

Estuaries are some of the most productive ecosystems on the planet. This inventory classifies more than 600 coastal confluences on the West Coast of the United States. Each estuary was classified using the federal Coastal and Marine Ecological Classification Standard (CMECS). A spatial database of…


2014 | Freshwater | Marine | Science | Publications & Reports

Nursery Functions of U.S. West Coast Estuaries: The State of Knowledge for Juveniles of Focal Invertebrate and Fish Species

Brent B. Hughes, Matthew D. Levey, Jennifer A. Brown, Monique C. Fountain, Aaron B. Carlisle, Steven Y. Litvin, Correigh M. Greene, Walter N. Heady, Mary G. Gleason

Estuaries support significant biodiversity and important ecosystem functions such as providing rearing habitat for juvenile fish and invertebrates. This report synthesizes the scientific literature and geospatial data on the nursery requirements of fifteen species of commercial, cultural, and conservation concern and highlights the potential nursery role…


2012 | Marine | Planning | Publications & Reports

Near-term priorities for the science, practice, and policy of Coastal and Marine Spatial Planning

Halpern, B.S., Diamond, J., Gaines, S., Gelcich, S., Gleason, M., Jennings, S., Lester, S., Mace, A., McCook, L., McLeod, K., Napoli, N., Rawson, K., Rice, J., Rosenberg, A., Ruckelshaus, M., Saier, B., Sandifer, P., Sholtz, A., Zivian, A.

This paper informs emerging efforts to implement coastal and marine spatial planning (CMSP) in the United States, Europe and elsewhere around the world. In order to identify priority needs for significantly advancing CMSP, the authors—expertsexperts in the science, policy and practice of CMSP—developed recommendations for…