Products

We identify issues and uncertainties that pose obstacles to conservation and then—in collaboration with internal and external colleagues—develop science products that help overcome those obstacles.

2018 | Terrestrial | Technology | Science | Publications & Reports

A test of desert shrub facilitation via radiotelemetric monitoring of a diurnal lizard

Michael F. Westphal, Taylor Noble, Harry Scott Butterfield, Christopher J. Lortie

Shrubs can play a key role in the structure of desert communities and can function as foundation species. Understanding desert shrub ecology is therefore an important task in desert conservation. In this study, the authors used radiotelemetry (technology used to track animals from a distance)…


2018 | Terrestrial | Economics | Science | Publications & Reports

Toward a Carbon Neutral California: Economic and Climate Benefits of Land Use Interventions

David C. Marvin, Dick Cameron, Erik Nelson, Andrew Plantinga, Justin Breck, Gokce Sencan, Michelle Passero

Ecosystems can increase carbon storage under alternative management techniques and land use patterns. But the magnitude, timing, and spatial heterogeneity is uncertain. Assessing the potential and cost of land management and conservation activities to reduce emissions or increase carbon sequestration is needed to help the…


2018 | Freshwater | Terrestrial | Science | Publications & Reports

The emergence of cannabis agricultural frontiers as environmental threats

Van Butsic, Jennifer K. Carah, Matthias Baumann, Connor Stephens, Jacob C. Brenner

While cannabis cultivation in California is known to sometimes have serious collateral impacts on the environment, those impacts and their extent are not well understood or described. In this paper, the authors quantify growth in the footprint of cannabis cultivation between 2012 and 2016 in…


2018 | Terrestrial | Science | Publications & Reports

Oren Pollak Memorial Research Fund - 2019 RFP

The Oren Pollak Memorial Research Fund was established in 2000 in memory of Dr. Oren Pollak, a leading grassland ecologist and restoration pioneer, as well as an ardent champion and mentor for grassland ecology students. As The Nature Conservancy’s lead ecologist in California in the…


2018 | Freshwater | Terrestrial | Science | Publications & Reports

Wetland Bird Conservation in California Rice Fields

Chris Elphick, T. Rodd Kelsey, Catherine Hickey, Khara Strum, Paul Buttner, Monica Iglecia

Wetland birds, especially Sandhill Cranes, are heavily dependent on irrigated farmlands in the Central Valley of California after widespread conversion of natural habitats. TNC and its partners have had great success working with farmers to design and implement compatible management practices that make sure farms,…


2018 | Freshwater | Terrestrial | Science | Publications & Reports

Waterbird response to variable-timing of drawdown in rice fields after winter-flooding

Kristen Sesser, Monica Iglecia, Matthew Reiter, Khara Strum, Catherine Hickey, Rodd Kelsey, Daniel Skalos

Over 50% of waterbird habitat in the Central Valley of California is provided by flooded agricultural land. Each year non-breeding waterbird habitat decreases in the late winter as flooded agricultural fields are drained after waterfowl hunting season in late-January to prepare for the next crop.…


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 | Planning | Economics | Science | Publications & Reports

Groundwater sustainability in the San Joaquin Valley: Multiple benefits if agricultural lands are retired and restored strategically

Rodd Kelsey, Abby Hart, H. Scott Butterfield, Dan Vink

Restoring habitat in retired farmland could reduce water demand and provide ecosystem services for farmers and local communities. In some areas of California, as a result of the Sustainable Groundwater Management Act (SGMA), it is likely that large amounts of agricultural land will need to…


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 | Planning | Science | Publications & Reports

Better late than never: a synthesis of strategic land retirement and restoration in California

Chris Lortie, Alex Filazzola, Rodd Kelsey, Abigail Hart, Scott Butterfield

Over the past 100 years, California's Central Valley has undergone a massive transformation from desert to a mosaic of farmland and urban development. This transformation has also meant many desert species have lost habitat. Now, new groundwater regulations are calling for the retirement of more…


2018 | Freshwater | Economics | Publications & Reports

California’s First Farmer-Led Groundwater Market

Sarah Heard, E.J. Remson, Siobhan King, Sandi Matsumoto

The Conservancy has a vested interest in preserving farms in Ventura County because they buffer important river and wetland habitat from nearby urban lands. In western Ventura County, over 70% of groundwater use is agricultural. Due to requirements of the Sustainable Groundwater Management Act (SGMA), this use will…


2018 | Freshwater | Terrestrial | Science | Publications & Reports

Impact of extreme drought and incentive programs on flooded agriculture and wetlands in California’s Central Valley

Matthew E. Reiter​, Nathan K. Elliott, Dennis Jongsomjit, Gregory H. Golet, Mark D. Reynolds

In the Central Valley of California, with 90% of the historic wetlands gone, waterbirds depend upon managed wetlands and seasonally flooded agriculture to meet their habitat needs. The 2013-2015 drought in the Central Valley was more severe than drought years during 2000-2011 and reduced waterbird…


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

Water Supply and Habitat Resiliency for a Future Los Angeles River: Site-Specific Natural Enhancement Opportunities Informed by River Flow and Watershed-Wide Action

Brian Cohen, Shona Ganguly, Sophie Parker, John Randall, Jill Sourial, and Lara Weatherly of The Nature Conservancy, Land IQ, Natural History Museum Los Angeles County, WRC Consulting Services Inc., Travis Longcore, University of Southern California, Connective Issue, Inc.

As a basic principle of ecological systems, a watershed’s hydrology determines the flow characteristics of its river system. These flows define what the biological characteristics of that river will be, which in turn determine what kinds of habitat enhancement projects will succeed at various locations along…


2018 | Terrestrial | Science | Publications & Reports

Oak habitat recovery on California's largest islands: Scenarios for the role of corvid seed dispersal

Mario B. Pesendorfer, Christopher M. Baker, Martin Stringer, Eve McDonald‐Madden, Michael Bode, A. Kathryn McEachern, Scott A. Morrison, T. Scott Sillett

A key aim of conservation is to restore ecological processes to degraded ecosystems. This study models how reintroducing an ecosystem engineer – the island scrub-jay, which is a highly efficient seed disperser – to a degraded island ecosystem could accelerate the recovery of its oak…


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

Ecological spillover dynamics of organisms from urban to natural landscapes

Jill E. Spear, Erik K. Grijalva, Julia S. Michaels, Sophie S. Parker

This paper discusses the impact of urban-dwelling plants and animals on regional wildland populations, both within and across species. The authors reviewed the global conservation literature and identified seven ecological processes that have the potential to be affected by spillover from urban to wildland areas.…


2018 | Freshwater | Planning | Publications & Reports

A freshwater conservation blueprint for California: prioritizing watersheds for freshwater biodiversity

Jeanette K. Howard, Kurt A. Fesenmyer, Theodore E. Grantham, Joshua H. Viers, Peter R. Ode, Peter B. Moyle, Sarah J. Kupferburg, Joseph L. Furnish, Andrew Rehn, Joseph Slusark, Raphael D. Mazor, Nicholas R. Santos, Ryan A. Peek, Amber N. Wright

Freshwater ecosystems are in peril globally. Threats to freshwater biodiversity are numerous and include habitat degradation, pollution, overexploitation, dam construction, species invasion, and hydroclimatic change. With conservation resources often limited, prioritization tooks are needed by land and water managers. To fill this need, the authors…


2018 | Freshwater | Science | Publications & Reports

Mojave Desert Springs and Waterholes: Results of the 2015-16 Mojave Desert Spring Survey

Prepared by Andrew Zdon & Associates Inc. for Transition Habitat Conservancy, The Bureau of Land Management, and The Nature Conservancy

The Mojave Desert within California, which spans four counties, exists as one of the most important ecological regions in the southwestern United States. Both the groundwater and surface water in the region support isolated, unique and diverse ecosystems, while also supporting human needs through domestic,…


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

Ecological Values of the Amargosa River in California

Sophie S. Parker, Jim Moore, Leonard Warren

The 185 mile-long Amargosa River, one of only two rivers with perennial flow in the California portion of the Mojave Desert, is fed by an ancient groundwater aquifer. The river provides habitat for hundreds of organisms, including a unique suite of rare, endemic, and imperiled…


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…


2018 | Marine | Technology | Science | Publications & Reports

Adaptive comanagement to achieve climate‐ready fisheries

Jono R. Wilson, Serena Lomonico, Darcy Bradley, Leila Sievanen, Tom Dempsey, Michael Bell, Skyli McAfee, Christopher Costello, Cody Szuwalski, Huff McGonigal, Sean Fitzgerald, Mary Gleason

Climate change is amplifying threats to ocean ecosystems and marine fisheries worldwide. In order to respond appropriately in the face of these ocean changes, commercial and recreational fisheries management requires improved information collection, expanded utilization of diverse data sources, and enhanced decision-making. While advances in science and…