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Marine Sciences Division

Rhonda Karls

Rhonda Karls

Marine Sciences Laboratory
Pacific Northwest National Laboratory
1529 West Sequim Bay Road
Sequim, Washington 98382


Ms. Rhonda Karls has worked at Battelle for 19+ years in the lab and out in the field. She has been lab lead, test supervisor, for varying tests and studies both fresh and saltwater. She's cultured different species of fish, amphipods, crustaceans, and algae. She's run several acute and chronic and multi-generational toxicity test and reference toxicant tests, using larval, juvenile and adult animals. She's initiated, observed, monitored water quality, and terminated a variety of tests, some of which required unique skills such as organ and tissue collection, injections and blood and hemolymph draws, and fish cannulations. She's helped fabricate and maintain special field and lab equipment such as aluminum framed rafts for carrying electronics and the diluters used during the endocrine study. She is a boat operator and has collected sediment, towed the video camera during off-shore studies, helped video the Clallam county coastline, participitated in the Puget Sound background radiation determination study.

Research Interests

  • Columbia River Channel Improvements Rock Blasting Project for USACE – Boat operator during a 3 1/2 month operation on the Columbia River at which time she operated the Strait Science. The team was responsible for making sure the blasting company stayed within compliance with the Marine Mammals Protection Act and minimized harm to other bird and fish life. Electronic equipment use to monitor fish flux and river conditions were deployed from the Strait Science. We worked in a variety of weather and river conditions without mishap or injury. Received an Outstand Performance Award for effort and teamwork in support of the project.
  • Chemical Repository – Involved in organization and tracking of chemicals used in Endocrine Disruptor studies. The Chemical Repository houses, ships and maintains all the chemicals used in studies around the world. GLP practices and standards are required in all repository activities. Most recently Ms. Karls participated in an extensive solubility study involving 26 chemicals dissolved at varying concentrations using different solvents and 5 different protocols. Solubility was determined by use of a dissecting scope and a micro plate reader.
  • Background Radiation Study – Operated Strait Science during a two week study of Washington State waters from Blaine to Tacoma then north to Port Angeles. Surveyed several marinas, shorelines, bridges, and boats recording normal background radiation levels. Required maneuvering boat in very tight quarters, passage through the locks into Lake Union and navigating Puget Sound and surrounding waters in all kinds of weather. Carried very delicate instruments and an assortment passengers onboard during study.
  • Endocrine Disruption Research – Ran several tests using Fathead minnows to determine affects of endocrine disrupting chemicals at different concentrations and durations. Diluters were used to run intermittent flow-through system during which adult minnows were exposed to chemical then observed for behavioral and physiological changes, survival and fecundity - normal/abnormal egg development. The diluters required a degree of technical expertise and diligent oversight.
  • Testing Ballast Water Organisms - Cultured algae to use in experiments to determine effective and efficient ways to terminate potentially harmful ballast water microorganisms. Used sterile technique to culture Selenastrum sp., designed test system and monitored throughout testing period. Used autoclave to sterilize glassware, and media.
  • Marine Biomass – maintained culture of assorted marine macroalgae to be use for biofuels research. Recorded water quality, light measements and kept a growth record of algae.
  • Evaluation of Fathead Minnow Substrate – Maintained in-house Fathead minnow culture for use in a multi -lab study of differences in spawning substrate used in minnow testing. Prepared 5 different substrates that were shipped to other laboratories with the intention of running simultaneous tests using the identical materials. Monitored comparison and kept track of complex testing schedule.
  • Information gathering related to offshore alternative and renewable energy – Used EndNote and other resources to help organize bibliographies and references gathered to create a repository of information relating the coastal and marine environments of Northern California, Oregon and Washington with emphasis on benthic invertebrates, fish and fisheries, birds, marine mammals and human interests.
  • Evaluating Cumulative Ecosystem Response to Habitat Restoration in the Columbia River Estuary Scope – Analyzed chlorophyll and Total Suspended Solid samples. Chlorophyll samples required special light conditions in order to optimize the integrity of the sample. Used TD-700 Laboratory Fluorometer to measure chlorophyll samples. Total suspended solids were determined by filtering water samples using a vacuum pump then placing filter in drying oven, weighing using an analytical balance then ashed and re-weighed.
  • City of Sequim – Collect water samples from Sequim Treatment Plant and offshore at 3 pre-determined stations near the treatment outfall for temp, pH, DO, salinity, nutrients, bacteria and surface layer. Responsibilities include boat operation, transporting person collecting samples to site using GPS, sonar and or radar, collect samples then prepare for shipment to independent lab for analysis.
  • Pilot Training Drills and Exercises – are on-going boat operations that are used to help train enforcement in locating and responding to incidents of radiation detection in the marine environment. I operate the Strait Science during these exercises. It’s not unusual to have boarding situations, radio communication with enforcement or other unusual circumstances.

Education and Credentials

  • 1991 A.A.S. Fisheries Technology Program, Peninsula College, Port Angeles, WA
  • 1979 Forest Harvesting & Rehab. Program, Edmonds Community College, Lynnwood, WA

PNNL Publications


  • Bryson A.J., C.M. Woodley, R.K. Karls, K.D. Hall, M.A. Weiland, Z. Deng, and T.J. Carlson, et al. 2013. "Comparison of 180-degree and 90-degree needle rotation to reduce wound size in PIT-injected juvenile Chinook salmon." Fisheries Research 143. PNNL-SA-91825. doi:10.1016/j.fishres.2013.02.011

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Marine Sciences Laboratory
1529 W. Sequim Bay Road
Sequim, WA 98382
Phone: (360) 683-4151
Fax: (360) 681-3699