2015 Summer Internship Program
Effects of Ocean Acidification on Reproduction and Development in the Copepod, Arctia Hudsonica
My name is Amanda “Mandy” Echevarría and I was given an amazing opportunity to participate in experimental data collection and laboratory analysis working with the copepod, Acartia hudsonica and phytoplankton, Rhodomonas salina. Under the direction and support of Dr. Julie Keister and Anna McLaskey, a graduate student in the School of Oceanography here at the University of Washington, we investigated how ocean acidification (OA) is affecting the reproduction and development of copepods. Alongside Drs. Brady Olson, Brooke Love and Katherina Schoo from Western Washington University and Shannon Point Marine Center in Annacortes, Washington, we all accomplished a lot this summer!
I started out my first week at UW with the Keister Lab group as they prepared for what would be the first of two rounds of two week experiments during our stay in Annacortes. After arriving in Annacortes we went straight to work going through copepod culture to find adult females with which to conduct the experiments which included: grazing rates conducted by Dr. Brady Olson and his intern, respiration rates conducted by Dr. Brooke Love and her intern, and reproduction and development conducted by Dr. Julie Keister, Anna McLaskey and myself. After two days of collecting a little over 1300 females, we started acclimating them to the filtered sea water that we had equilibrating at different carbon dioxide (CO₂) levels; ambient at 400 ppm, moderate at 800 ppm and high at 1200 ppm. We collected different water chemistry samples from the jars in which we kept the copepods to double check the carbon content of the water through pH, decomposed inorganic carbon (DIC) and alkalinity. Water and copepods in jars were housed in plexiglass boxes and were stored in a 12 degree Celsius cold room. I did everything from cleaning jars, feeding females and nauplii, to setting up different experiments, counting eggs, dead nauplii and hot gluing 64 µm mesh to PBC pipes. The range of tasks was exhilarating, even during the 11pm feedings.
After two weeks in Annacortes, Anna, Julie and I returned to UW where I went through 129 development jars and counted unhatched eggs and nauplii. By measuring the nauplii I was able to tell what development stage they had made it to after having been laid as eggs 8 days prior to preservation. The data I focused on was the proportion of eggs that hatched and how many nauplii made it to each development stage.
After the principal investigators discussed the data that had been collected thus far, they decided that the next round of experiments would be done at 17 degrees Celsius, that 5 degree difference not only meant fewer layers required in the cold room, but also felt like a balmy summer day (granted, this was all done in July). So after a two week break, it was back up to Annacortes. However, this time we were sure we completed some sort of World Record for copepod picking with a little over 1600 copepods picked in 2 days! We repeated everything with more replicates this time and by the end had ~475 jars of nauplii and eggs preserved.
As busy as I was, I did find time to get out and explore Seattle. I made it out on a few hikes in the surrounding Cascades, went and saw the Mariners and Sounders play, took in a theater production at the Paramount Theater downtown, toured the Underground and even picked some blackberries around campus. I learned so much that it is impossible to express how much I appreciate all of the experiences I had in this beautiful state. I met some very amazing people that share my aspirations to make a difference in this world. A huge thank you to the team at JISAO for making this all possible and the Keister Lab, especially Julie and Anna, for the countless hours we spent caring for our copepods and all the guidance and hands-on learning I received. I will be reminiscing about this summer and using the skills I learned here for a long time to come.
Click on image for full size PDF