Investigating calcification patterns in Mytilus californianus shells from Alaska to search for shifts in morphology and microstructural properties across the later Holocene

Project Title

Investigating calcification patterns in Mytilus californianus shells from Alaska to search for shifts in morphology and microstructural properties across the later Holocene

Faculty Mentor(s)

Project Description

Mytilus californianus – a coastal bivalve mollusk in the family Mytilidae – is a marine species that spans a broad latitudinal range across the eastern north Pacific Ocean in wave-exposed coastlines stretching from Baja California to the Aleutian Islands of Alaska.  In addition to the expansive range of this species, M. californianus has also remained integral to the culture, economy, and diet of native coastal communities for thousands of years.  In many cases, this species' calcium carbonate shell remains are remarkably well preserved in archaeological middens across its inhabited range, providing a potential paleoenvironmental record throughout the Pleistocene-Holocene transition (approximately 11,700 years before present).  

Today, this species is essential to study in the context of human-induced climate change into the later Holocene, especially in climate-sensitive regions such as polar and subpolar zones, and is vital to our understanding of species' adaptation, vulnerability, and ecology within these locales. Understudied in the Alaska region, my independent research is part of a long-term project that aims to broaden our knowledge of the modern geographic scope of M. californianus to include the full latitudinal range of this species. In my research, I characterize the shell structure, morphology, and composition of M. californianus shells from Alaska and investigate signs of rapid microstructural changes in response to recent environmental shifts from the 19th to the 21st century.

Why is your research important?

The California mussel holds vital clues into how the environment changes over time.  As the shells of the California mussel grow and precipitate calcium carbonate, the mechanisms that control that growth also record environmental stresses in the shell formation.  Put differently, the shells of the mussel serve as archives for an individual's growth history. By looking at individuals across time, we can reconstruct the growth history of the species from a given region under certain oceanographic conditions (such as acidification levels) and environmental constraints.

What does the process of doing your research look like?

There are two main components to my research.  One of the components of my research is field collecting modern California mussel specimens from intertidal regions of Alaska.  In the summer of 2024, I received internal and external research grants to work in southeastern Alaska to collect specimens to aid my research. The other component of my work is obtaining specimen loans of archival California mussels from institutions (such as museums and universities) so that I can comparatively study with the modern shells to reconstruct the growth history of this species over time.  This has led me to obtain shells on loan from institutions such as the Smithsonian, the University of California Museum of Paleontology, and the University of Alaska Museum of the North.  I collect morphometric data and use instruments such as the Scanning Electron Microscope and the Mass Spectrometer located in the Geosciences department to collect microstructural data related to the crystallography and composition of the shells.

What knowledge has your research contributed to your field?

This project is expanding our knowledge of the California mussel into the northern geographic range of this species. Little research has yet to be undertaken to understand the growth mechanisms of this species from this region. It is vital to know how these individuals respond to climate change compared to their southern counterparts (from California and Baja California). This project also maintains a broader focus on human community impacts. It aims to contribute knowledge to understanding how parts of the ecosystem that Native communities have relied upon for subsistence for thousands of years are changing with a changing climate – ultimately impacting traditional ecological knowledge and lifeways.    

In what ways have you showcased your research thus far?

My research has been showcased in interviews with local southeastern Alaska radio stations.  My research interview as a visiting scientist with the Sitka Sound Science Center can be found here on the KCAW radio station. Additionally, my research has been showcased to the Oberlin community through the communications department at Oberlin, where I speak about my summer experience in the field in Alaska (found here). Other showcases of my work include Winter Term Fairs and Lab Crawl events. 

How did you get involved in research? What drove you to seek out research experiences in college?

I got involved with my research after forming a strong relationship with my PI, Dr. Veronica Padilla Vriesman (previously an Assistant Professor of Geosciences at Oberlin and now an Assistant Professor of Environmental Science at Scripps/Pitzer).  Dr. Veronica Padilla Vriesman’s focus on studying culturally significant bivalve species allowed me to explore my passion for understanding human-environment interactions in polar and subpolar regions.  My drive to investigate issues through an interdisciplinary lens drove me to seek out research opportunities in college.

What is your favorite aspect of the research process?

My favorite aspect of the research process is the relationships I have formed with the people I have emailed and called throughout my work.  I have developed lasting relationships with local communities in southeastern Alaska, research partners at the University of Alaska Southeast and UC Davis, head officials at the Alaska Department of Fish and Game, and even local naturalists across Alaska.   

How has working with your mentor impacted the development of your research project? How has it impacted you as a researcher?

Dr. Veronica Padilla Vriesman has been a fantastic PI for my research! Dr. Zeb Page has also been an incredibly resourceful on-campus mentor for my work and instrumentation usage here at Oberlin.  At the end of the ‘23-’24 academic year, Dr. Veronica Padilla Vriesman moved institutions to Scripps/Pitzer.  Although this transition occurred, we have continued regular meetings with the continuous collection of promising data!  I genuinely believe that this is a testament to our passion for this research and our desire to see this project through to the stages of publication.

How has the research you’ve conducted contributed to your professional or academic development?  

My research has contributed to my academic development by making me more enthusiastic about my passions for polar sciences and studies.  It has given me avenues to think critically about what I want from my research and how it will shape my future in graduate school while also considering how I can give back to the communities in which my work looks.

What advice would you give to a younger student wanting to get involved in research in your field?

My advice to a younger student getting involved in research in my field would be to learn to accept denial and find ways to build off of that.  There may be instances where you put weeks into writing grant proposals or significant effort into writing specimen loan/destructive sampling requests, only for the final answer to be a “no.”  With enough perseverance and drive to find success in your project, it might make all those emails and calls you sent out worth it when it comes to seeing your research advance!