Research

Broadly, I am interested in the role of foundation species in supporting ecosystem functioning and services. I am currently a Ph.D. candidate at the University of California, Santa Cruz, where I study the resilience and recovery of kelp forest ecosystems. I focus on the recruitment of giant kelp, Macrocystis pyrifera, by investigating its survival following recruitment into urchin barrens, as well as competition and grazing within its early life stages. I also conduct research on the kelp-connected human community in the Monterey Bay area to understand perspectives on kelp loss, recovery, and restoration.

My research journey began at Brown University, where I studied oceanographic drivers of biodiversity in the Galapagos Islands, to Florida International University, where I worked as a lab manager investigating the climatic and biological drivers of seagrass ecology in the Gulf of Mexico and Caribbean.

Kelp forest resilience and recovery

In the Raimondi-Carr Lab at UCSC, I pursue my interest in foundation species by studying kelp forest ecosystems. The recent declines in kelp forests in central and northern California provide an opportunity to ask fundamental ecological questions: What factors drive diverse ecosystems to near collapse? How can we predict the persistence of foundation species faced with local and global stressors? What factors prohibit or facilitate the recovery of kelp into kelp-free urchin barrens? I use field observation through SCUBA, statistical modeling, and mesocosm experiments to answer these questions throughout my Ph.D.

Kelp forest recovery in a former urchin barren

A 2014 marine heatwave led to kelp forest losses throughout California, including >90% in Northern California and patchy but significant declines in Central California. This created vast "urchin barrens", with abundant, active urchins preventing the recovery of kelp.

At Hopkins Marine Station in Monterey, I set up and monitored 40 permanent, 1m x 1m plots in an urchin barren that spontaneously started recovering into an urchin barren, allowing me to look at before and after data on urchin abundance and behavior, as well as kelp recruitment, growth, and survival.

This work is ongoing, but preliminary results suggest that a massive shift in urchin foraging behavior - changing from active, exposed grazing while it was a barren, to passive, hidden behavior while during recovery - was associated with the sudden increase in kelp recruitment. Additionally, despite frequent mortality kelp recruits survived far better once they hit a certain size threshold (~1m tall), suggesting that fast growth leads to a size refuge from competition and grazing.

Competition and grazing on the early life stages of giant kelp

Kelps undergo a fascinating life cycle where adult individuals, also called sporophytes, release trillions of microscopic spores into the water. Those spores "germinate" into a life stage called gametophytes which release eggs and sperm. When those egg and sperm meet, a juvenile microscopic sporophyte is formed, which then grows into an adult and the cycle begins again.

The microscopic stages are difficult to study, yet play a crucial role in kelp's recolonization of urchin barrens. As a part of my dissertation and the Kelp RISES project, I am investigating how these early life stages (spores, gametophytes, and juvenile sporophytes) compete with one another and how grazing by sea urchins interacts with competition to influence successful recruitment.

Perspectives on kelp restoration in Monterey Bay

Most of my research focuses on the ecological drivers of kelp forest recovery, but human-mediated recovery, i.e. restoration, is increasingly proposed as a way to bring back lost forests. In the Monterey Bay area, community members have a wide range of kelp connections, from fishing, kelp harvesting, underwater photography, research, and much more. In this project, also a part of the Kelp RISES project, I conducted semi-structured interviews of kelp-connected community members to ask: how do humans interact with and perceive kelp forests and kelp restoration? This information will be used to understand the linkages in this kelp social-ecological system while also informing the in-development Kelp Restoration and Management Plan (KRMP) about the range of priorities and perspectives of those closest to the kelp.

Western Atlantic seagrasses and global change

Seagrasses are declining globally due to local and global stressors including nutrient eutrophication and global warming. In the year before my Ph.D., I worked as a lab manager at Florida International University, studying how Western Atlantic seagrass responds to global changes in the Campbell Global Change Biology Lab. There, I spearheaded data analysis in the R statistical software for an NSF funded project called the Thalassia Experimental Network (TEN), investigating how the Turtlegrass Thalassia testidinum responds to experimentally induced nutrient additions and grazing. See my publications page for some recently published work from this project!

Photo by Justin Campbell

Marine communities in the Galapagos Islands

As an undergraduate at Brown, I studied marine communities in the Galapagos Islands through the Witman Lab. For my senior thesis (manuscript in prep), I used caging experiments in the field to investigate how bottom up effects (oceanographic upwelling) and top-down effects (predation/herbivory) interact to structure benthic communities of macroalgae and sessile invertebrates. I also contributed to additional observational and experimental studies, including a project looking at how reef fish communities respond to El Niño events, how reef fish biodiversity is influenced by oceanographic gradients, and how damselfish territories serve as productive algal oases on the benthos.

Photo by Alejandro Perez-Matus

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