About 175 in-person and online attendees gathered for Bigelow Laboratory for Ocean Sciences’ (BLOS) final Café Sci lecture of the 2025 season, Aug. 6, on the East Boothbay campus. “Ocean Epidemiology: Tracking Marine Diseases to Protect Fisheries and Ocean Health” (video) introduces the Quantitative Marine Disease Ecology Lab (Q-MoDEL), a team of scientists dedicated to understanding the drivers and consequences of marine diseases. After a brief introduction by Jim McManus, Bigelow’s new VP of Administration and Operations, the floor was given to Dr. Maya Groner, senior research scientist and Q-MoDEL team lead. She highlighted how diseases, much like those in terrestrial environments, range from mildly interesting parasites to highly impactful pathogens like avian influenza in marine mammals and sea star wasting disease.

Her presentation emphasized that environmental factors, particularly climate change and rising temperatures, significantly influence disease prevalence and severity in marine species. The Q-MoDEL lab aims to diagnose, predict and manage these diseases, especially those affecting ecologically vital species and economically important fisheries with dollar values: $584 million for crabs, $563 million for lobsters, $488 million for scallops, $478 million salmon and $435 million in shrimp according to the National Oceanic and Atmospheric Administration (NOAA). Dr. Reyn Yoshioka and Dr. Melissa Rocker addressed crabs and lobsters, respectively, in their presentations.

Yoshioka spoke of Black Eye Syndrome, an emerging condition affecting Alaskan snow crabs, characterized by eye discoloration and severe tissue damage leading to blindness. The condition's origins are mysterious: Its cause is unknown and not attributed to a specific pathogen, making environmental conditions (warmer ocean temperatures) the primary focus of study. He discussed how large-scale data sets and oceanographic modeling are crucial for understanding such marine diseases, particularly in the context of snow crab population collapse in the Bering Sea. “Between 2019 and 2021, an estimated 10 billion snow crabs were lost from the stock in the Bering Sea. This event led to the closure of the snow crab harvest in Alaska for the first time in history,” he said. While Black Eye Syndrome isn't considered the primary cause of the collapse, it may indicate environmental stress on the crab population that contributed to their mass starvation. He further showed the increased instances of Black Eye Syndrome overlaid with warmer ocean temperatures, emphasizing the need for continued monitoring of marine species' health in changing climates. Yoshioka enjoys teaching tomorrow’s ocean scientists. He has created “Crabdemics” – a board game based on his research.

Rocker’s work explores epizootic shell disease (ESD) in lobsters, particularly focusing on its impact on the American lobster populations in Southern New England and the Gulf of Maine. She discussed how rising water temperatures contribute to the prevalence and severity of ESD, causing aesthetic damage that makes lobsters unmarketable and potentially leading to mortality during molting. Through experimental tank studies with lobsters from different regions, the research team found that Maine lobsters exposed to warmer waters developed more severe and faster-progressing disease but also molted more frequently, potentially as a recovery mechanism. This data (observed historically and confirmed through experimental research) informs an individual-based model that simulates future ESD risk in lobster populations based on environmental changes, aiming to assist fishery managers and the public in understanding and predicting the disease's progression. Initial signs of ESD can appear around 54°F, and when temperatures reach 68°F, widespread severe disease is observed.

Rocker’s experiments confirmed that Maine lobsters exposed to warm water developed more severe disease, and the disease progressed faster; temperature drives lobsters' seasonal molting patterns. While lobsters can die directly from ESD or from complications during molting, experiments showed that lobsters in warm water were more likely to molt, shedding their diseased shell to recover to a healthy state. Groner hinted that future research will investigate whether increased molting cycles come at a cost of reproduction and subsequent impact on the lobster population.

Groner emphasized the crucial role of multi-disciplinary collaboration among modelers, experimentalists, students and agencies in understanding these complex interactions, promoting better management strategies, and how advanced modeling capabilities enable learning from past events to prepare for challenges.