Project Funding: 2011 - 2017

NRA: 2009 NASA: Interdisciplinary Research in Earth Science   

Funded by NASA

Abstract:
The San Francisco Estuary is the largest estuary on the Pacific coast of the United States and the largest wetland habitat in the western U.S. The estuary is a critical ecosystem that links freshwater and marine environments providing essential habitat for fish, drinking water to over 22 million urban users, and irrigation water for agriculture in the highly productive Central Valley. Over the past century the estuary has been substantially altered structurally and the current configuration and water management approach has been repeatedly designated as unsustainable. While the estuary receives nearly one half of California’s runoff, the quantity and quality of the incoming water has substantially decreased over time, and diversions from within the estuary can be as high as 50%. The estuary is also impacted from the marine side, with oceanographic processes such as the Pacific Decadal Oscillation (PDO) and the North Pacific Gyre Oscillation (NPGO) leaving strong imprints on the estuarine ecosystem. In the past few years, the deterioration of the estuary has risen to crisis levels, with native fish populations collapsing, and resource managers being forced to take unprecedented and controversial actions, including curtailing water deliveries to drought-afflicted farmers. Chinook salmon depend on river, estuarine and marine ecosystems and are an ideal study organism for improving our understanding of the shared hydrology between these systems. The unprecedented closure of the entire salmon fishery in California in 2008 and 2009 was due to the collapse of the Sacramento River fall Chinook salmon (SRFC), the largest and most economically important population of salmon in California. An exhaustive review by the National Marine Fisheries Service (NMFS) of the factors behind this collapse found that poor feeding conditions experienced by the juveniles when they entered the ocean was the proximate cause of the fishery collapse - but that the ultimate cause of the collapse was due to degradation of freshwater and estuarine habitats. Because the health and dynamics of the San Francisco Estuary are so tightly linked to the rivers that feed it (90% of the water comes from the Sacramento River), the amount of water diverted from within it, and the oceanographic processes of the ocean it discharges into, it is necessary to study all three systems and their linkages simultaneously. This landscape level task is virtually impossible without the use of NASA Earth Sciences data. We propose to use NASA earth sciences data to drive a series of coupled physical-biological simulations that will produce key physical (temperature) and biological (food supply) variables for the river, estuary and coastal ocean. These inputs will then be incorporated into a Dynamic Energy Budget (DEB) model for Chinook salmon to explore how salmon respond to freshwater dynamics as they grow from eggs to mature adults while moving across this complex landscape. The DEB model will provide insight into drivers of variation in salmon growth and maturation, two of the most important parameters for understanding salmon population dynamics. This work represents the first attempt to simultaneously model the entire early life history (freshwater, estuarine, and coastal ocean habitats) of a salmon species to provide mechanistically based evaluations of the impacts of current and future water management and climate scenarios. To our knowledge this would be the first time that stream and estuarine models will be coupled with a basin-scale ocean model. This proposed work would provide the ecosystem models needed as the basis of the ecosystem-based management and ecological risk assessment framework needed to improve management of water and fishery resources in California.

Publications:

Fiechter, J., Huff, D. D., Martin, B. T., Jackson, D. W., Edwards, C. A., Rose, K. A., Curchitser, E. N., Hedstrom, K. S., Lindley, S. T., Wells, B. K. 2015. Environmental conditions impacting juvenile Chinook salmon growth off central California: An ecosystem model analysis. Geophysical Research Letters. 42(8), 2910-2917. DOI: 10.1002/2015gl063046

Martin, B. T., Heintz, R., Danner, E. M., Nisbet, R. M. 2017. Integrating lipid storage into general representations of fish energetics. Journal of Animal Ecology. 86(4), 812-825. DOI: 10.1111/1365-2656.12667

Martin, B. T., Nisbet, R. M., Pike, A., Michel, C. J., Danner, E. M. 2015. Sport science for salmon and other species: ecological consequences of metabolic power constraints. Ecology Letters. 18(6), 535-544. DOI: 10.1111/ele.12433

Martin, B. T., Pike, A., John, S. N., Hamda, N., Roberts, J., Lindley, S. T., Danner, E. M. 2016. Phenomenological vs. biophysical models of thermal stress in aquatic eggs. Ecology Letters. 20(1), 50-59. DOI: 10.1111/ele.12705

Nisbet, R. M., Martin, B. T., de Roos, A. M. 2016. Integrating ecological insight derived from individual-based simulations and physiologically structured population models. Ecological Modelling. 326, 101-112. DOI: 10.1016/j.ecolmodel.2015.08.013

More details may be found in the following project profile(s):

• NASA Biological Diversity & Ecological Conservation (BDEC) Project Profile