Leadership Team – Cramer Fish Sciences

Brad Cavallo, M.S.

Vice President, Principal Scientist

B.S. Fisheries Biology; M.S. Aquatic Ecology

Phone: (530) 240-6448

Auburn, California

Brad has more than 23 years of experience working on anadromous and estuarine fishery issues in California and has attained expert knowledge of regulated rivers and estuaries, particularly related to the ecology of Chinook Salmon and other anadromous fishes. Brad excels in high-level data analysis including life-cycle modeling and simulation modeling of management impacts and the development, application, and evaluation of quantitative models for assessing aquatic habitats and fish population dynamics. Brad previously served as an environmental scientist with the California Department of Water Resources and was the lead scientist for hydropower re-licensing.

Selected Publications

Abadia-Cardoso, A., A. Brodsky, B. Cavallo, M. Arciniega, J. J. Garza, J. Hannon, and D. Pearse. 2019. Anadromy redux? Genetic analysis of Upper American River rainbow trout Oncorhynchus mykiss to inform development of an indigenous steelhead broodstock for Nimbus Hatchery. North American Journal of Fisheries Management. In final review.

Lessard, J., B. Cavallo, P. Anders, T. Sommer, B. Schreier, D. Gille, A. Schreier, A. Finger, T. C. Hung, J. Hobbs, and B. May. 2018. Considerations for the use of captive-reared delta smelt for species recovery and research. San Francisco Estuary and Watershed Science 16(3).

Cavallo, B., et al. 2016. Coleman National Fish Hatchery Adaptive Management Plan. Report to the U.S. Department of the Interior, Bureau of Reclamation, Manton, California.

Cavallo, B., P. Gaskill, J. Melgo, and S. C. Zeug. 2015. Predicting juvenile Chinook routing in riverine and tidal channels of a freshwater estuary. Environmental Biology of Fishes 98(6):1571-1582.

Delaney, D., P. Bergman, B. Cavallo, and J. Melgo. 2014. Stipulation study: steelhead movement and survival in the South Delta with adaptive management of Old and Middle River flows. Technical Report to the California Department of Water Resources, Sacramento, California.

Zeug, S. C., and B. J. Cavallo. 2014. Controls on the entrainment of juvenile Chinook salmon (Oncorhynchus tshawytscha) into large water diversions and estimates of population-level loss. PLoS One 9(7):e101479. DOI:10.1371/journal.pone.0101479.

Cavallo, B., J. Merz, and J. Setka. 2013. Effects of predator and flow manipulation on Chinook salmon (Oncorhynchus tshawytscha) survival in an imperiled estuary. Environmental Biology of Fishes 96(2-3):393-403.

Merz, J., M. Workman, D. Threloff, and B. Cavallo. 2013. Salmon life cycle considerations to guide stream management: examples from California’s Central Valley. San Francisco Estuary and Watershed Science 11(2).

Zeug, S. C., and B. J. Cavallo. 2013. Influence of estuary conditions on the recovery rate of coded wire tagged Chinook salmon (Oncorhynchus tshawytscha) in an ocean fishery. Ecology of Freshwater Fish 22:157-168.

Merz, J., S. Hamilton, P. Bergman, and B. Cavallo. 2012. Spatial perspective for delta smelt: a summary of survey data. California Fish and Game 97(4):164-189.

Cavallo B., R. Brown, and D. Lee. 2009. Hatchery and genetic management plan for Feather River hatchery spring-run Chinook program. Report to the California Department of Water Resources, Sacramento, California.

Seesholtz, A., B. Cavallo, J. Kindopp, and R. Kurth. 2004. Juvenile fishes of the lower Feather River: distribution, emigration patterns, and associations with environmental variables. Pages 141–166 in F. Feyrer, L. R. Brown, R. L. Brown, and J. J. Orsi, editors. Early Life History of Fishes in the San Francisco Estuary and Watershed. American Fisheries Society, Symposium 39, Bethesda, Maryland.

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Gregg Schumer

Vice President, Director of Lab Services, Senior Molecular Biologist
B.S. Molecular, Cellular, and Developmental Biology
Phone: (916) 231-1687

West Sacramento, California

Gregg has two decades of experience applying molecular biological techniques in the fields of human pathogens, vaccine production, molecular ecology, fisheries genetics, and the detection of cryptic aquatic species by environmental DNA (eDNA). Gregg has led the effort within CFS to transfer relevant molecular biological and genetics technologies from the world of human pathogens to the study of fish ecology. Gregg leads the development of protocols and techniques for identifying and evaluating the distribution of cryptic, invasive, and listed or endangered aquatic species by eDNA.

Selected Publications

Blankenship, S., G. Schumer, J. Van Eenennaam, and Z. Jackson. 2017. Estimating number of white sturgeon adults from egg relatedness. Fisheries Management and Ecology 24(2):163-172.

Finger, A., G. Schumer, A. Benjamin, A. Schreier, and S. Blankenship. 2017. Effective population size of delta smelt. San Francisco Estuary and Watershed Sciences.

Bergman, P., G. Schumer, S. Blankenship, and E. Campbell. 2016. Detection of adult green sturgeon using environmental DNA analysis. PLoS One 11:e0153500. DOI: 10.1371/journal.pone.0153500.

Schreier, B. M., M. R. Baerwald, J. L. Conrad, G. Schumer, and B. May. 2016. Examination of predation on early life stage delta smelt in the San Francisco estuary using DNA diet analysis. Transactions of the American Fisheries Society 145(4):723-733.

Brandl, S., G. Schumer, B. M. Schreier, J. L. Conrad, B. May, and M. R. Baerwald. 2015. Ten real-time PCR assays for detection of fish predation at the community level in the San Francisco Estuary-Delta. Molecular Ecology 15(2):278-284.

Baerwald, M. R., B. M. Schreier, G. Schumer, and B. May. 2012. Detection of threatened delta smelt in the gut contents of the invasive Mississippi silverside in the San Francisco Estuary using TaqMan Assays. Transactions of the American Fisheries Society 141(6):1600-1607.

Hamelin, M. E., M. Baz, Y. Abed, C. Couture, P. Joubert, É. Beaulieu, N. Bellerose, M. Plante, C. Mallett, G. Schumer, G. P. Kobinger, and G. Boivin. 2010. Oseltamivir-resistant pandemic A/H1N1 virus is as virulent as its wild-type counterpart in mice and ferrets. PLoS Pathogens 6(7):e1001015. DOI:10.1371/journal.ppat.1001015

Baerwald, M. R., G. Schumer, B. M. Schreier, and B. May. 2011. TaqMan assays for the genetic identification of delta smelt (Hypomesus transpacificus) and wakasagi smelt (Hypomesus nipponensis). Molecular Ecology Resources 11(5):784-785.

Blankenship, S., M. Teply, and G. Schumer. 2011. Sampling and analysis to assess brook trout (Salvelinus fontinalis) population trends in High Lake (Oregon) using environmental DNA monitoring. Report to Burns Paiute Tribe.

Kobinger, G. P., H. Feldmann, Y. Zhi, G. P. Schumer, G. P. Gao, F. Feldmann, S. Jones, and J. M. Wilson. 2006. Chimpanzee adenovirus vaccine protects against Zaire Ebola virus. Journal of Virology 346(2):394-401.

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Joseph E. Merz, Ph.D.

President, Principal Scientist, Adjunct Professor (UCSC)

B.S. Environmental and Systematic Biology; M.S. Biological Conservation; Ph.D. Conservation Ecology

Phone: (916) 250-2344

West Sacramento, California

Joe has more than 26 years of experience working for state, city, university, and public entities as a fisheries ecologist and performing studies and monitoring fish populations to protect and enhance their habitat. He has completed numerous assessments of habitat manipulation on aquatic resources, including habitat enhancement, flow manipulation, invasive species removal, and regulation implementation, particularly for Chinook salmon and steelhead. Joe has extensive experience with habitat typing and delineation with the use of GIS and aerial maps, has designed multi-million dollar projects to restore river channels and floodplains, and has trained numerous professionals in these techniques.

Selected Publications

Sturrock, A. M., S. M. Carlson, J. D. Wikert, T. Heyne, S. Nusslé, J. Merz, H. Sturrock, R. C. Johnson. 2019. Un-natural selection of salmon life histories in a modified riverscape. Global Change Biology. https://doi.org/10.1111/gcb.14896

Harrison, L. R., E. Bray, B. Overstreet, C. J. Legleiter, R. A. Brown, J. E. Merz, R. M. Bond, C. L. Nicol, and T. Dunne. 2019. Physical controls on salmon redd site selection in restored reaches of a regulated, gravel-bed river. Water Resources Research 55. https://doi.org/10.1029/2018WR024428.

Anderson, J. T., G. Schumer, P. J. Anders, K. Horvath, and J. E. Merz. 2018. Confirmed observation: a North American green sturgeon Acipenser medirostris recorded in the Stanislaus River, California. Journal of Fish and Wildlife Management 9(2):624-630.

Merz, J. E., L. Caldwell, M. Beakes, C. Hammersmark, and K. Sellheim. 2018. Balancing competing life stage requirements in salmon habitat rehabilitation: between a rock and a hard place. Restoration Ecology. Early View only. DOI: 10.1111/rec.12900.

Gundersen, D. T., S. C. Zeug, R. B. Bringolf, J. E. Merz, Z. Jackson, and M. A. H. Webb. 2017. Tissue contaminant burdens in San Francisco estuary white sturgeon (Acipenser transmontanus): implication for population recovery. Environmental Contamination and Toxicology 73(2):334-347.

Sellheim, K., M. Willmes, J. A. Hobbs, J. J. G. Glessner, Z. J. Jackson, and J. E. Merz. 2017. Validating fin ray microchemistry as a tool to reconstruct the migratory history of white sturgeon Acipenser transmontanus. Transactions of the American Fisheries Society 146(5):844–857.

Merz, J. E., D. G. Delaney, J. D. Setka, and M. L. Workman. 2016. Seasonal rearing habitat in a large Mediterranean-climate river: management implications at the southern extent of pacific salmon (Oncorhynchus spp.). River Research and Applications 32(6):1220-1231.

Merz, J. E., P. S. Bergman, J. L. Simonis, D. Delaney, J. Pierson, and P. Anders. 2016. Long-term seasonal trends in the prey community of delta smelt (Hypomesus transpacificus) within the Sacramento-San Joaquin Delta, California. Estuaries and Coasts 39(5):1526-1536.

Sabal, M., S. Hayes, J. Merz, and J Setka. 2016. Habitat alterations and a nonnative predator, the striped bass, increase native Chinook salmon mortality in the Central Valley, California. North American Journal of Fisheries Management 36(2):309-320.

Sellheim, K. L., M. Vaghti, and J. E. Merz. 2016. Vegetation recruitment in an enhanced floodplain: Ancillary benefits of salmonid habitat enhancement. Limnologica 58:94-102.

Sellheim, K., C. Watry, B. Rook, S. Zeug, J. Hannon, J. Zimmerman, K. Dove, and J. Merz. 2015. Juvenile salmonid utilization of floodplain rearing habitat after gravel augmentation in a regulated river. River Research and Applications 32(4):610-621.

Anderson, I. J., M. K. Saiki, K. Sellheim, and J. E. Merz. 2014. Effect of Didymoshenia geminata blooms on benthic macroinvertebrates in the Lower American River California. Southwestern Association of Naturalists 59(3):389-395.

Merz, J., T. M. Garrison, P. S. Bergman, S. Blankenship, and J. C. Garza. 2014. Morphological discrimination of genetically distinct Chinook salmon populations: an example from California’s Central Valley. North American Journal of Fisheries Management 34(6):1259-1269.

Merz, J. E., P. S. Bergman, J. F. Melgo, and S. Hamilton. 2013. Longfin smelt: spatial dynamics and ontogeny in the San Francisco Estuary, California. California Fish and Game 99(3):122-148.

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Lael Gorsek, B.S.

Controller

B.S.

Phone: (888) 224-1221

Portland, Oregon

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Philip Roni, Ph.D.

Vice President, Principal Scientist, Affiliate Professor (UW)

B.A. Business Administration (Marketing); M.S. Fisheries Science; Ph.D. Aquatic and Fishery Sciences

Phone: (206) 960-4484

Issaquah, Washington

Phil has nearly 30 years of experience as a fisheries research scientist and directs the CFS Northwest science team. He focuses on designing, implementing, completing, and publishing definitive studies to address pressing questions related to protection, management, and restoration of aquatic systems. His research for the last 20 years has concentrated on planning, prioritization, and evaluation of various watershed restoration techniques. He regularly teaches courses and has published numerous papers on restoration science, including the comprehensive book, “Stream and Watershed Restoration: A Guide to Restoring Riverine Processes and Habitats” (2013 Wiley-Blackwell).

Selected Publications

Krall, M. P. Roni, C. Clark, and K. Ross. 2021. Effects of livestock exclusion on stream banks and riparian vegetation in Washington and Oregon. Northwest Science 95: 1-21.

Clark, C., P. Roni, J. Keeton, and G. Pess. 2020. Evaluation of the removal of impassible barriers on anadromous salmon and steelhead in the Columbia River Basin. Fisheries Management and Ecology 27:102-110.

Roni, P., J. E. Hall, S. M. Drenner, and D. Arterburn. 2019. Monitoring the effectiveness of floodplain habitat restoration: A review of methods and recommendations for future monitoring. Wiley Interdisciplinary Reviews: Water:e1355.

Roni, P. 2019. Does river restoration increase fish abundance and survival or simply concentrate fish? The effects of project scale, location, and fish life history. Fisheries 44:7-19.

Roni, P., P. J. Anders, T. J. Beechie, and D. J. Kaplowe. 2018. Review of tools for identifying, planning, and implementing habitat restoration for Pacific salmon and steelhead. North American Journal of Fisheries Management 38(2):355-376.

Roni, P., Johnson, C., T. De Boer, T. and G. Pess. 2016. Interannual variability in the effects of physical habitat and parentage on Chinook salmon egg-to-fry survival. Canadian Journal of Fisheries and Aquatic Sciences 73:1-13.

Roni, P., T. Beechie, C. Jordan, and G. Pess. 2015. Basin scale monitoring of river restoration: recommendations from case studies in the Pacific Northwest USA. Pages 73–98 in N. Fisher, P. LeBlanc, C. A. Rose, and B. Sadler, editors. American Fisheries Society, Symposium 78, Bethesda, Maryland.

Roni, P., T. Beechie, G. Pess, and K. Hanson. 2015. Wood placement in river restoration: fact, fiction and future direction. Canadian Journal of Fisheries and Aquatic Sciences 72(3): 466-478.

Roni, P., and T. Beechie. 2013. Stream and watershed restoration: a guide to restoring riverine processes and habitats. Wiley-Blackwell, Chichester, U.K.

Roni, P., T. Bennett, R. Holland, G. Pess, K. Hanson, R. Moses, M. McHenry, W. Ehinger, and J. Walter. 2012. Factors affecting migration timing, growth and survival of juvenile coho salmon in two coastal Washington watersheds. Transactions of the American Fisheries Society 141: 890-906.

Roni, P., G. Pess, S. T. Beechie and S. Morley. 2010. Estimating changes in coho salmon and steelhead abundance from watershed restoration: how much restoration is needed to measurably increase smolt production? North American Journal of Fisheries Management 30:1469-1484.

Roni, P., K. Hanson, and T. Beechie. 2008. Global review of physical and biological effectiveness of stream rehabilitation. North American Journal of Fisheries Management 28:856-890.

Roni, P. 2005. Monitoring stream and watershed restoration. American Fisheries Society, Bethesda, Maryland.

Roni, P., T. J. Beechie, R. E., Bilby, F. E. Leonetti, M. M. Pollock, and G. P. Pess. 2002. A review of stream restoration techniques and a hierarchical strategy for prioritizing restoration in Pacific Northwest watersheds. North American Journal of Fisheries Management 22:1-20.

Roni, P., and T. P. Quinn. 2001. Effects of artificial wood placement on movements of trout and juvenile coho salmon in natural and artificial channels. Transactions of American Fisheries Society 130:675-685.

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