Akiko: Invertebrate settlers project

My name is Akiko Onuma, and I am lucky enough to be one of the COSEE Pacific Partnership PRIME interns. About a week ago, I wrapped up my finals and projects at Portland Community College and moved out here to the Oregon Institute of Marine Biology in Charleston, Oregon. It’s my fourth day here and so far I’ve had a pretty awesome time!

On my first day of the program, I met with my mentor, Dr. Richard Emlet, to get an idea of the purpose of my project. He told me about the many different invertebrates living in the two boat basins in Charleston. A few of them include colonial invertebrates, where hundreds of tiny individual organisms make up a larger colony. The organisms that I will be studying are called fouling species, meaning that they attach themselves to hard surfaces underwater. Most of them look like slime growing on rocks or boat hulls, which is how they got their name "fouling organisms". My project will be to make a photographic timeline/identification key that will look at a variety of these marine invertebrates from when they are very small to when they are much bigger. Most of these organisms go through a larval period, meaning that they start off as a microscopic swimmer floating through the water. Soon, they find a hard surface and settle down on it, undergoing metamorphoses in order to attach themselves to the substrate. Then, they start to “grow” by asexual reproduction, which basically means making more of yourself in order to start a colony. It is the colony that is visible to the naked eye, and identifiable. So my job is to take pictures of these species from the time when they first settle (attach themselves to the surface of my petri dishes) until they are big enough to be identified.





This is the harbor where I will be deploying my petri dishes to collect settling invertebrates.




Harbors and marinas are often hotbeds for introduced and invasive species because boats will pick up and distribute these hitch-hiking species wherever they dock, much like the marks left by a child playing with a jar of glitter. One particularly important introduced species is called Didemnum vexillum. This colonial organism, which looks like pale orange slime growing on the rocks, is an invasive species. Scientists believe that this organism originally came from Japan, but it is showing up in docks all over the world. Didemnum has documented presence in Japan, New Zealand, France, Ireland, California, New Hampshire, and now recently has started settling in Oregon. Furthermore, once introduced, Diademnum grows rapidly and can cover large areas in a short period of time, out competing other native species for space and resources.



Diademnum is an introduced species to the Charleston inner boat basin, and has only been here for a couple of years.