This summer, I worked at the Northwest Fisheries Science Center with Paul Chittaro. My main project this summer was looking at the latitudinal and annual patterns of somatic growth for Pacific Hake along the U.S. Pacific Coast. Pacific Hake is an important forage fish as well as being valuable in commercial fishing. They were collected over three years at different latitudes along the Pacific Coast.
In the lab, we measured the fish for length and weight. I then dissected the fish for its otolith. An otolith is the equivalent to a human inner ear bone. Hake otoliths are usually elongated oval-shaped bones. Otoliths are useful for determining growth in fish because they have rings, like a tree, that indicate the growth of the fish on regular increments, in my case daily. We can use these rings to estimate the size and growth rate of a fish.
After removing the otolith, I then mounted them onto microscope slides, and they were polished to make the core and rings visible. Once polished, the otoliths were photographed underneath a microscope. These images were analyzed on the computer for the otolith radius at time of capture, and the otolith radius 7 days prior to capture. These values would allow use to estimate growth and their total length 7 days before capture.
Also as a part of my hake work, I worked on Blue Lanternfish. They are another important forage fish on the Pacific Coastline. They were collected at the same time as the Hake, and I did the same processes with them.
Another project I got to assist with this summer is a kelp and eelgrass isotope project. I got to go out on the boat to collect fish and invertebrates near Mukilteo and the San Juan Islands for isotope analysis. Those were very really fun days!
Overall, I learned a lot this summer, and got to have many great experiences in the lab and in the field. I would like to my mentor Paul Chittaro and JISAO for this opportunity. I also would like to thank everybody else at the Northwest Fisheries Science Center for help.