By Damian Amerman-Smith, Pacific High School senior, GEMM Lab summer intern
Growing up in Port Orford, a short ten-minute walk from the Pacific Ocean, has certainly shaped my life a lot. It has given me a great regard for the ocean, the diversity of life within it, and how life seems to bypass human derived borders in order to go wherever it can. I often marvel at all the beautiful, intricate ecosystems that are able to exist inside of our planet’s vast oceanic expanses. Along with my love of the ocean has come a great regard for marine mammals and the novelties of these animals that allow them to live entirely in the ocean despite not having gills. Every new discovery of these beautiful ocean creatures brings me such simple and pure joy, such as my very recent discovery that baleen whales have two blow holes. These blow holes look so peculiar on the top of their bodies, like a short upside-down nose.
My interest in the ocean and its inhabitants was a large part of what made me so enthused to take a part in the gray whale foraging ecology (GWFE) project in Port Orford this summer. When Elizabeth Kelly, my friend and a previous intern for the GWFE project mentioned her experiences from the previous summer, I was very happy when she put me in contact with Lisa Hildebrand and Leigh Torres so that I could apply to be an intern. Since then, I have been very ecstatically awaiting the beginning of the project and could hardly believe it when it finally began, and I was able to meet my fellow team members: Lisa Hildebrand, the PhD student who has been leading the GWFE project for the last four years; Allison Dawn, a Master’s student who is going to take over the project in Lisa’s stead; Nadia Leal, an OSU undergrad hoping to further pursue the field of marine biology; and Jasen White, an OSU undergrad whose time in the Navy has made him a very steeling presence while out on the water.
The three weeks that we have spent together learning the procedures that make up the project have been well spent, teaching all of us a lot of new things, such as what a theodolite is, how to operate a dissolved oxygen sensor, and (for me) how to use Excel. The first two weeks were largely spent just learning about how we collect data and improving our field skills, but as we have become more comfortable with our skills, we have also begun looking beyond the procedures, towards the data itself and what it can mean. Primarily, we started to notice the distinct lack of gray whales and almost complete lack of zooplankton prey for any gray whales in the area to eat.
As we pass the halfway point in the project, we have only witnessed two whales inside our study area. While in the beginning it was not surprising that there were no whales, it has started to become concerning to me. We have a strong working hypothesis about why there have not been many whale sightings in our monitored sites of Mill Rocks and Tichenor’s Cove: there is not nearly enough zooplankton prey to attract them. Monday, August 9th is a good example to support this hypothesis. On that day, when we pulled up our sample net at Tichenor Cove station #1, we collected fifty-three individual Neomysis mysid shrimp, which are a tasty treat for gray whales. However, all the other prey samples from the remaining eleven kayak sampling stations had perhaps a maximum of five assorted zooplankton each, which is certainly not enough to attract the attention of such a large predator as Eschrichtius robustus (a gray whale). Unfortunately, we have yet to see much change in zooplankton prey availability in our sampling nets over the season so far, but we are hopeful that swarms of zooplankton in the area will resurge and the gray whales will begin using the area around the port as their August feeding grounds.
Our hopes aside, it is intriguing to think about why there has been so few zooplankton at our sampling sites. A main factor is likely the decrease of Port Orford’s kelp forests over the past few years. Kelp is very important to zooplankton, particularly mysids, as it allows them to seek shelter from predators. Declines in kelp forests have been documented all along the southern Oregon coast, and are believed to be fueled by many factors (ORKA, 2021). A combination of warming waters with decreasing amount of nutrients available to the kelp (Richardson 2008), and the increasing abundances of purple sea urchins that eat the kelp has vastly impacted the amount of kelp in the area. The decline in local kelp forests may be the reason that we are seeing fewer mysid swarms than in previous years. This reduced kelp and mysid availability could, in turn, be making Port Orford waters an unappetizing area for hungry whales to visit this year. While this trophic cascade is still just an educated hypothesis, it is important for us and others to keep watch on the situation, and to see how it changes. There are organizations such as the Oregon Kelp Alliance (ORKA) that are working hard to study why the kelp populations are hurting and how we can help. We will power through the season with the hopes that the gray whales will come. It is still very possible that the zooplankton will resurge and the whales will return with plenty to feed on.
Richardson, Anthony J. 2008. In hot water: zooplankton and climate change, ICES Journal of Marine Science, Volume 65, Issue 3, Pages 279–295, https://doi.org/10.1093/icesjms/fsn028
ORKA, 2021. “Kelp.” Oregon Kelp Alliance, www.oregonkelp.com/.