Molecular Biologist and Marine Scientist, University of Southern California

Two divers on ocean floor

Maddelyn Harden'ts focus lies at the intersection of marine science, international policy, and climate resilience, where she aims to influence global environmental policy through data-driven solutions and collaborative efforts.

What is your current occupation?

I am currently a Research Associate in the Nuzhdin Lab in the Molecular Biology Department at the University of Southern California. 

Please tell us a little bit about yourself. 

I am deeply passionate about conservation and biodiversity research, with over 10 years of experience in field biology and marine science. From monitoring salmonid populations in Humboldt County, CA, to conducting scientific diving courses at the Wrigley Marine Science Center off the coast of Catalina Island, I have developed a strong foundation in hands-on conservation work. My career journey began with a focus on sustainable fisheries and coastal resource management, shaped by transformative experiences in the Galapagos Islands and Maine. Over time, I have worked with multiple regulatory agencies, including California Fish & Wildlife and the US Fish & Wildlife Service, before transitioning to a role as a resident marine biologist at a sustainable aquaculture startup. My goal is to apply this diverse experience to advancing the scientific understanding of ecosystem management and conservation in the face of global challenges.

My PhD in molecular biology, where I focused on understanding the genetic underpinnings of kelp heat stress response, aimed to improve our understanding of how climate change impacts kelp forests and their role in marine ecosystems. I am now a research associate at the Nuzhdin lab in the molecular biology department at USC, where I continue to expand my research on molecular mechanisms in marine organisms.

My first experience using HOBO Pendant loggers was during my work with California Fish & Wildlife, where I assisted in salmonid surveys. Later, while conducting bivalve seaweed sustainability research at USC, I had the opportunity to use the Bluetooth version of the HOBO Pendants for the first time. This time, the loggers were deployed in an open ocean environment, and I found them to be exceptionally effective for real-time data collection under challenging conditions. I also continued using the Bluetooth version of the HOBO loggers for ex-situ experiments on kelp gametophytes in the laboratory, where I used them to collect light and temperature data, ensuring the accuracy and reliability of the experimental conditions

What do you like to do when you’re not at work?

I am a crime and mystery genre nerd, so I love to read novels and spy thrillers, like John le Carre – and Agatha Christie, of course. Also, in 2020 when all the gyms were closed, my partner and I began what is now an annual tradition of running half-marathons; a hobby that keeps us running together weekly.

In addition to my work in the lab, I am deeply committed to bridging policy and actionable science initiatives. I serve as the Policy Chair for the American Fisheries Society California-Nevada Chapter, and Co-Chair for the Policy & Advocacy Subcommittee with the Genetic Society of America’s Early Career Leadership Program. I am also a Commission Member with the International Union for the Conservation of Nature’s Coastal Ecosystem Management Group. Through these positions, I work closely with professional organizations to ensure that policy decisions are informed by the latest scientific research, working to drive meaningful conservation outcomes.

What is your area of expertise? 

I am a molecular biologist and marine scientist by training. At the University of Southern California, I earned my PhD in molecular biology, which includes seaweed genetics. My professional and academic history prior to my PhD was as a marine scientist and fisheries biologist. 

What is your primary motivation for doing the work that you do? 

My primary motivation has always been environmental stewardship, a passion that has been with me since childhood. My academic background in molecular biology and marine science at the University of Maine further deepened my commitment to understanding and conserving marine ecosystems. While environmental stewardship remains my top priority, I am equally driven by the goals of sustainable development, impactful research, and policy engagement. I firmly believe that without the foundational work of geneticists, biologists, ecologists, and zoologists, meaningful and effective policy initiatives cannot be achieved.

What would you say is your greatest accomplishment?

I consider my greatest accomplishment (to date) to be earning my PhD, which focused on understanding the genetic underpinnings of giant kelp’s heat stress response. As a conservationist, I am particularly proud of how this work not only advanced scientific knowledge but also contributed to conservation efforts. By linking my research to the broader field of ecosystem preservation, I was able to make a meaningful impact on the future of marine biodiversity.

What do you strive to achieve in the future?

In the future, I hope to lead projects focused on sustainable fisheries development, working at the intersection of science, policy, and fisheries management. My goal is to ensure that my work and research have a tangible, positive impact in the real world, contributing to the sustainable management of marine resources.

Have you ever thought about the word HOBO and what it might mean? 

I always assumed it was an acronym and meant something very specific to the tool itself. 

What HOBO products do you use on a regular basis?

I use the HOBO Pendant MX2201 Water Temperature Data Logger, and of course the HOBOconnect app. I really appreciate the functionality in HOBOconnect that allows me to name each Pendant and set specific time intervals. These features are incredibly important for ensuring accurate data collection and for managing multiple loggers efficiently.

Please describe a specific project of yours where HOBO Data Loggers played a key role. 

HOBO data loggers were crucial to my PhD research, which focused on understanding the genetic underpinnings of kelp heat stress response. I developed a novel protocol to induce heat stress in kelp gametophytes (the seed-like stage of kelp) by creating a heat stress panel and exposing various genotypes to different temperature regimes. The goal was to determine how they responded to varying heat stress thresholds. The HOBO loggers played an essential role in ensuring that specific temperature conditions were maintained, and the data collected confirmed that. As a result, we were able to identify genes potentially involved in heat stress response and pinpoint specific genotypes that perform better under heat stress conditions than others.

What HOBO features do you consider most important?

Bluetooth functionality is one of my favorite features—it makes everything so easy! Additionally, I really appreciate the ability to name each Pendant in HOBOconnect, which helps me keep track of which incubator each one is in. The flexibility to finely adjust the monitoring intervals is incredibly useful. Throughout all my use of HOBO loggers, I've never had one exhibit erratic behavior or fail to log data. They are undoubtedly some of the most reliable instruments I’ve ever worked with.

Do you think accurate data can help build a better tomorrow?

Yes, absolutely. Approximately 60% of the world’s kelp forests have been decimated due to global climate change. Accurate, high-quality data is essential for building a better tomorrow by providing the necessary information to address critical questions, such as: Can we identify a population of kelp that is naturally heat stress-tolerant? How can we leverage this knowledge to improve restoration efforts? By relying on precise data, we can develop informed strategies for preserving and restoring vital marine ecosystems.

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