1992 M.S. Oceanography, Florida Institute of Technology, Melbourne,FL
1990 B.A. Physics, University of Virginia, Charlottesville, VA
I am preparing two publications on my postdoctoral research experience at the Northwest Fisheries Science Center in Seattle, Washington, where I designed and carried out fish feeding experiments on larval and juvenile coldwater marine species (rock sole, rockfish, Pacific cod, etc.). I used a variety of live and inert feeds to investigate the transfer of nutrients from zooplankton to ichthyoplankton utilizing several methods: HPLC, GC, and inert markers (ICP). At the Northwest Fisheries Science Center, I recently completed two projects on fish growth and nutrient utilization, which are being prepared for publication: 1.) protein replacement diets for lingcod Ophiodon elongatus utilizing Alaskan fisheries by-product and by-catch meals, and 2.) a rapid method to measure the relative uptake of live prey and inert feeds fed to larval finfish.
The larval marker work will be repeated soon with Pompano Trachinotus carolinus in collaboration with the USDA researchers Marty Riche and Chuck Weirich at the Harbor Branch Oceanographic Institution in Vero Beach, FL.
"The Future of Our Planet: Climate, Ecosystems, and Society." Co-instructors: Susan Bates (Atmospheric Sciences); Lisa Marin (Biology) - 2 credit seminar
Spring 2007: TESC 408, University of Washington, Tacoma (sole instructor)
"Marine Plankton" - 6 credit lecture/lab
2008 Summer Institute on Statistical Genetics Scholarship Recipient, University of Washington, Seattle
2008 Howard Hughes Medical Institute Future Faculty Fellows, University of Washington, Teaching Apprenticeship: "The Future of Our Planet: Climate, Ecosystems and Society"
2007 University of Washington Postdoctoral Research Symposium Speaker
2005 Plenary Speaker, World Association of Copepodologists Section on the Role of Copepods in Aquaculture, 9th ICOC
2003 U.S. Peace Corps Graduate Service Assistantship, North Carolina State University
2002 1st Place Student Poster Award, World Aquaculture Society
2001 Starr Fellowship, Bermuda Biological Station for Research
2000 University Alumni Fellowship, North Carolina State University
2000 Aylesworth Scholarship, Florida Sea Grant
1996 Dean John A. Knauss Marine Policy Fellowship, National Sea Grant, NOAA1992 Aylesworth Scholarship, Florida Sea Grant
1992 Citizen's Environmental Appreciation Award, Indian River Lagoon National Estuary ProgramI have recently started to incorporate a functional and
comparative genetic approach to my research on larval fish development and
copepod biology. I feel that this
approach can provide valuable information on basic physiological processes,
such as digestive enzyme development in marine fish and lipid storage in marine
copepods. Once these physiological
processes have been characterized in the species of interest, I will be able to
measure organismal responses to environmental stressors such as reduced prey
availability, ocean acidification, the presence of endocrine disruptors and
other forms of pollution. By monitoring
the expression levels of select genes in laboratory cultures of copepods and/or
fish larvae subjected to abiotic and biotic stresses such as toxic algal
species and temperatures outside the optimum range we could predict the impacts
to the food chain from these possible threats to ecosystem health.
DELTA-6 DESATURASE
This study seeks to find evidence of the proposed conversion pathways of highly unsaturated fatty acid in copepods. A variety of copepod species have been collected and their genomic DNA was. Primers were developed for the most common desaturases responsible for HUFA conversions: delta-6, delta-5, etc. One of the challenges that had to be overcome in the search for appropriate primers is the lack of information in the genetic databases. In many cases, these desaturases, while well-described in higher vertebrates, had only been definitively described for a handful of invertebrate species.
While I am still early in the search, some preliminary sequences are quite promising. They conform to the length and homology of other desaturases found in the genetic databases. Curiously, two delta-6 desaturase sequences were found from the Tigriopus californicus species, so the mRNA will be sampled again to determine if one or both versions of the gene are being expressed. This poster was presented at the 10th International Conference on Copepoda in Pattaya, Thailand, July, 2008.
REGULATION OF DIAPAUSE
I am awaiting funding to possibly pursue another postdoctoral project to characterize the genes involved in the triggering of diapause in an important copepod species at the base of the food chain in the Northern Pacific region,
Neocalanus plumchrus. If successful in obtaining funds, some of the methods I will use include suppression subtraction hybridization, differential display, and Expressed Sequence Tag (EST) analysis. In collaboration with Dr. Steven Roberts in the School of Aquatic and Fishery Sciences at UW, I will generate cDNA libraries for Neocalanus copepods prior to, during, and following diapause. I hope to characterize several differentially expressed genes as well as a number of previously unidentified genes that could play important roles in the timing of diapause. This work will provide some insights into how food quality and oceanic temperature changes may impact the base of the Northern Pacific food chain that supports a variety of fish and marine mammal species. If you are interested in finding out more about this work and possibly collaborating, please contact me at acer@u.washington.edu.
In my second year as a postdoctoral researcher at UW, I returned
to aquaculture. As a postdoc funded by the USDA ARS and University of Idaho by Dr. Ron Hardy, I assisted Dr. Michael Rust in the development of larval and
juvenile fish feeds for two major projects being conducted at the NOAA Northwest Fisheries Science Center Montlake facility in Seattle near the UW.
One project tested the efficacy of utilizing Alaskan fisheries by-product and by-catch meals as part of larval and juvenile fish diets. The second project analyzed the uptake of various prey items through the trophic food chain utilizing a variety of live feeds fed inert metal oxides and then fed to larval finfish. During my time at NOAA Fisheries, I also worked on constructing a functional hatchery scale copepod production system to produce millions of copepods per day for research and analysis of the transfer of nutrients. We are awaiting further funding to complete and field test this pilot system.
In my first year as a postdoctoral researcher at UW, I assisted the Ballast Water Research Team under the supervision of Russell Herwig and Jeff Cordell at the University of Washington.
My role in the team was to provide and maintain cultures of nearly forty species of freshwater and marine zooplankton, many of them started from field samples. These cultures were utilized in a range of tests designed to improve the Environmental Technology Verification (ETV) process. The ETV process screens promising new technologies for the reduction of non-indigenous species introduction through ballast water exchange. After culturing and screening the microzooplankton species, we developed a short list of seven surrogate organisms that could potentially be used to represent the response of a much broader group of organisms.
We then developed and conducted ecotoxicological assays for microzooplankton using ten proposed ballast water treatment technologies (e.g. ozone, UV, several biocides). After screening, I collected the data from the hundreds of experiments conducted by our lab and our collaborators at Woods Hole, West Virginia University and Old Dominion and prepared a comprehensive database tool for comparing and analyzing the effectiveness of proposed treatments for ridding ballast tanks of bacteria, phytoplankton, protists and zooplankton. The database results were presented to representatives from the EPA, NOAA, and U.S. Coast Guard at a scientific panel meeting in 2007. The U.S. Coast Guard and the Smithsonian Environmental Research Center will make this database tool available to researchers around the world as part of the National Ballast Information Clearing House (NBIC).
Due to my expertise with culturing and maintaining
phytoplankton and zooplankton cultures, I often help local colleagues develop
and implement experiments involving zooplankton. For example, working with colleagues from the
Department of Oceanography at UW, Dr. Anitra Ingalls and Dr. Carme Huguet, I
will be assisting in a study of how copepod ingestion of Crenarchaeota may impact lipid biomarkers. Crenarchaeota lipid biomarkers are used to determine the change in
surface water temperatures over time, and it is possible that the encapsulation
of Crenarchaeota in calanoid faecal
pellets may alter the lipid biomarkers.
This experiment will involve field sampling of zooplankton that reside
in the water column alongside the Crenarchaeota
as well as laboratory experiments to measure the key lipid biomarkers in
copepod faecal pellets.
attachment.
Most recently, I assisted in the first comprehensive zooplankton survey of the Puget Sound. I assisted NOAA scientists in plankton tows, and I identified the key species collected during the cruise while sorting out samples for my own genomic analyses. I am working on submitting the novel genes I have isolated and identified from Pseudocalanus sp. and Calanus pacificus to NCBI's Genbank. In cooperation with the same team, I hope to expand my genomics work to include a differential expression analysis of zooplankton, ichthyoplankton and bivalve veligers to ocean acidification conditions.
GENBANK ENTRIES (2008):
EU590909 Pseudocalanus sp. 18S ribosomal RNA gene, partial sequence
EU590910 Pseudocalanus sp. Eaf elongation factor-2 mRNA, partial cds
Rhodes, A. 2007. Dietary effects on carotenoid composition in
the marine harpacticoid copepod Nitokra
lacustris. Journal of Plankton Research 29(Supplement 1):i73-i83.
Rhodes, A. and L. Boyd. 2005. Formulated feeds for harpacticoid copepods: Implications for population growth and fatty acid composition. In: C.S. Lee, P. J. O'Bryen and N. H. Marcus (Eds.) Copepods in Aquaculture, Blackwell Publishing, Oxford, UK, pp. 61-73.
ISBN 0-8138-0066-8
Rhodes, A. 2003. Methods for mass culture of Nitokra lacustris, a marine harpacticoid copepod. In: H.I. Browman and A.B. Skiftesvik (Eds.). The Big Fish Bang. Proceedings of the 26th Annual Larval Fish Conference. Institute of Marine Research, Bergen, Norway, pp: 449-465.
ISBN 82-7461-059-8
Rhodes, A. 2004. Marine Harpacticoid Copepod Culture for the Production of Long Chain Highly Unsaturated Fatty Acids and Carotenoid Pigments. Ph.D. Dissertation, North Carolina State University, 161 pp.
POSTER PRESENTATIONS
Last modified: 7/29/2008 4:23 PM