Ruddy Duck Ruddy Duck
Photo Credit: Tom Grey


Current Research

Joint Venture Partners are currently working on projects to address high priority needs identified in the Monitoring and Evaluation Plans.

Completed Research

Over the course of its history, the Central Valley Joint Venture has built a strong body of research to support the scientific recommendations and priorities reflected in the 2006 Implementation Plan. See below for a list of that research.

Hunting Success in the Central Valley, California, During 1995-96 Compared with Previous Years.

Hunting success is important to the Joint Venture's wetland conservation programs, and the hunting public needs to be kept informed about factors that control the availability of waterfowl and hunter success. In response to changes in hunting regulations and a resulting dissatisfaction with hunting success during the 1995-96 hunting season, the Joint Venture Technical Committee assessed hunter success during that time compared to recent years and provided explanations for documented differences and similarities. They concluded that total harvest and hunter success in 1995-96, did not differ enough from recent trends to warrant major changes in habitat or harvest management at that time.

Technical Guide to Best Management Practices for Mosquito Control in Managed Wetlands

The CVJV prepared this document to present a full range of Best Management Practice (BMP) options specific to managed wetlands. This technical guide was developed to provide information on habitat management strategies to reduce mosquito production in managed wetlands, and to facilitate greater cooperation among wetland habitat managers and Mosquito and Vector Control Districts (MVCDs). The BMPs identified in this guide are also an essential component of Integrated Pest Management (IPM) for mosquitoes, which incorporates knowledge of mosquito biology and the use of effective treatments to control mosquitoes while posing the least risk to people and the environment.

Ecology of northern pintails and other waterfowl during spring in Southern Oregon - Northeastern California (SONEC) Southern Oregon-Northeastern California (SONEC) provides critical spring staging habitat for northern pintails and other waterfowl in the Pacific Flyway. This multi-phased project used a variety of methods to: Measure timing, distribution, and magnitude of use by pintails and other waterfowl; Identify important spring habitats and quantify day and night use by pintails; Map dynamics and distribution of waterbird spring habitat in SONEC; Determine waterfowl food habits in spring-flooded pasture and hayfields; Quantify density of waterbird foods in spring-flooded pasture and hayfields, and; Determine the body condition of waterfowl migrating through SONEC in spring.

Avian Disease in the Central Valley of California: A Survey of Trends 1980-2001 examines trends in avian botulism and avian cholera exploring potential relationships between recent habitat restoration efforts within the valley and waterfowl disease mortality.

Avian Monitoring on Private Lands. To document and assess the success of their efforts on private lands, the CVJV and partners have initiated the Avian Monitoring on Private Lands (AMPL) project in collaboration with Point Blue Conservation Science. AMPL is a cooperative effort, involving the California Department of Fish and Game’s Landowner Incentive Program and California Waterfowl Habitat Program, the U.S. Fish and Wildlife Service’s Partners for Fish and Wildlife Program, the Natural Resource Conservation Service’s Wetlands Reserve Program, Point Blue Conservation Science, the Central Valley Joint Venture, and private landowners.

Breeding Shorebird Survey. Little is known about shorebird status in the Central Valley in summer, a period when wetland habitat reaches its annual nadir and for which wetland loss has been even greater than at other seasons. To fill this important data gap, the CVJV helped support Point Blue Conservation Science to coordinate counts of potentially breeding shorebirds at wetlands and other shallow-water habitats throughout the Central Valley in June 2003. Multiple federal, state, academic, and private partners were involved in the surveys.

In a final report submitted to the CVJV and in a paper currently being reviewed for publication, Point Blue Conservation Science reports the patterns of geographic distribution, abundance, and broadscale habitat use of the Black-necked Stilt and American Avocet, the shorebird species most representative of these habitats in the Central Valley. Point Blue Conservation Science also identifies threats to nesting shorebirds and makes recommendations for management and research needed to ensure the effective conservation of their populations and habitat in this region.

Discovery for Recovery: An International Pintail Recovery Initiative (The Pinsat Project) addressed the low population status of northern pintail ducks by seeking to understand relationships among regional waterfowl habitats and continental population demographics.

Evaluating Moist-Soil Seed Production and Management in Central Valley Wetlands to Determine Habitat Needs for Waterfowl (1) evaluates the amount of food available in Central Valley wetlands; (2) investigates the influence of wetland management on seed production in wetlands; and (3) develops a new technique for monitoring wetland seed production.

The Pacific Flyway Project was the first ever attempt to establish baseline data on the abundance and distribution of shorebirds in wetland habitats along the Pacific Flyway from Alaska to Baja California. Data from the Pacific Flyway Project provide information critical to current shorebird conservation planning decisions, including the management of wetlands in the Central Valley.

Surveys of California's Central Valley between 1992-1995 document it as one of the most important regions in western North America to migratory and wintering shorebirds. Development of a sound conservation strategy is crucial for the preservation of shorebird populations in the Central Valley, as this agriculturally-dominated landscape is among the most altered in North America and remains vulnerable to strong economic and population growth pressures that may impact shorebird habitats in the future.

PG&E’s Avian Protection Plan. For the past 25 years, CVJV Management Board member PG&E has led various bird protection efforts. They work collaboratively with organizations such as the U.S. Fish and Wildlife Service to minimize the dangers that transmission lines and other electrical equipment pose to birds. PG&E’s Avian Protection Plan seeks to protect migratory, threatened and endangered birds from these risks.

The Pintail Action Group is a cooperative group of public and private interests dedicated to the conservation of the northern pintail duck. The pintail, which was once one of the most common waterfowl species in North America, has declined over the past several decades due to changes in land-use practices.

The US Geological Survey, in partnership with the CVJV, has supported and benefited from extensive research including the following projects. For more information about individual researchers and their projects, visit

  • Miller, M.R., E.G. Burns, B.E. Wickland, and J.M. Eadie. 2009. Diet and body mass of wintering ducks in adjacent brackish and freshwater habitats. Waterbirds 32(3):374-387.
  • Miller, M.R., and J.M. Eadie. 2006. The allometric relationship between resting metabolic rate and body mass in wild waterfowl (Anatidae) and an application to estimation of winter habitat requirements. Condor 108:166-167
  • Miller, M.R., J.Y. Takekawa, J.P. Fleskes, D.L. ORthmeyer, M.L. Casazza, and W.M. Perry. 2005. Spring migration of northern pintails from California's Central Valley wintering area tracked with satellite telemetry: routes, timing, and destinations. Canadian Journal of Zoology 83:1314-1332.
  • Fleskes, J.P., J.L. Yee, M.L. Casazza, M.R. Miller, J.Y. Takekawa, and D.L.Orthmeyer. 2005. Waterfowl distribution, movements, and habitat use relative to recent habitat changes in the Central Valley of California: A cooperative project to investigate impacts of the Central Valley Joint Venture and changing agricultural practices on the ecology of wintering waterfowl. Final Report. U.S. Geological Survey-Western Ecological Research Center, Dixon Field Station, Dixon, California. [Technical Report]
  • Ackerman, JT, JY Takekawa, DL Orthmeyer, JP Fleskes, JL Yee, and KL Kruse. 2005. Response of greater white-fronted geese to the Central Valley Joint Venture: changes in wintering ecology over a decade. 11th North American Arctic Goose Conference and Workshop, Reno, Nevada, January 5–8. [Poster]
  • Ackerman, JT, JY Takekawa, JP Fleskes, and DL Orthmeyer. 2005. White-fronted geese respond well to Joint Venture's habitat improvements. Valley Ventures, Spring 2005: 10-13. [Popular Publication]
  • Ackerman, JT, JY Takekawa, JP Fleskes, and DL Orthmeyer. 2005. Decade of change: a tracking study shows how white-fronted geese responded to recent habitat changes in the Central Valley. California Waterfowl, April/May 2005: 16-17 & 58. [Popular Publication]
  • Fleskes, J. P., D. S. Gilmer, and R. L. Jarvis. 2005. Pintail distribution and selection of marsh types at Mendota Wildlife Area during fall and winter. California Fish and Game 91(4): 270-285. [Journal Article]
  • Fleskes, J. P., W. M. Perry, K. L. Petrik, R. Spell, and F. Reid. 2005. Change in area of winter-flooded and dry rice in the northern Central Valley of California determined by satellite imagery. California Fish and Game 91(3): 207-215. [Journal Article]
  • Fleskes, J.P., R. L. Jarvis, and D. S. Gilmer. 2002. Distribution and movements of female northern pintails radiotagged in San Joaquin Valley, California. Journal of Wildlife Management 66(1):138-152. [Journal Article]
  • Fleskes, J. P., R. L. Jarvis, D. S. Gilmer. 2002. September-March survival of female northern pintails radiotagged in San Joaquin Valley, California. Journal of Wildlife Management 66(3): 899-909. [Journal Article]
  • Miller, M. R., J. P. Fleskes, J. Y. Takekawa, D. L. Orthmeyer, M. L. Casazza, and W. M. Perry. 2001. Satellite tracking of northern pintail spring migration from California, USA: the route to Chukotka, Russia. Casarca 7: 229-233. [Journal Article]
  • Miller, M.R., and W.E. Newton. 1999. Population energetics of northern pintails wintering in the Sacramento Valley, California. Journal of Wildlife Management 63:1222-1238.
  • Miller, M.R., and G.D. Wylie. 1996. Preliminary estimate of rice present in strip-harvested fields in the Sacramento Valley, California. California Fish and Game 82:187-191.
  • Miller, M.R., J.P. Fleskes, D.L. Orthmeyer, W.E. Newton, and D.S. Gilmer. 1995. Survival of adult female northern pintails in Sacramento Valley, California. Journal of Wildlife Management 59:478-486.
  • Miller, M.R., D.E. Sharp, D.S. Gilmer, and W.R. Mulvaney. 1989. Rice available to waterfowl in harvested fields in the Sacramento Valley, California. California Fish and Game 75:113-123.
  • Miller, M.R. 1987. Fall and winter foods of northern pintails in the Sacramento Valley, California. Journal of Wildlife Management 51:405-414.
  • Miller, M.R. 1986. Northern pintail body condition during wet and dry winters in the Sacramento Valley, California. Journal of Wildlife Management 50:189-198.
  • Ackerman, J., J. Y. Takekawa, D. L. Orthmeyer, J. P. Fleskes, J. L Yee, and K. L. Kruse. In press. Spatial use by wintering greater white-fronted geese relative to a decade of habitat change in California's Central Valley. Journal of Wildlife Management XX:xxx-xxx. [Journal Article]


The CVJV partnership has earned an impressive record of accomplishment since its inception in 1988, and is making great progress towards meeting the objectives identified in its 2020 Implementation Plan.