Short Wave: The Great Antarctic Food Web Puzzle

Host: Regina Barber
Guest: Biologist Martina Mascioni
Release Date: March 10, 2025

Introduction to Phytoplankton

In the episode titled "The Great Antarctic Food Web Puzzle," NPR's Short Wave delves into the crucial role of phytoplankton in the Antarctic ecosystem. Host Regina Barber introduces phytoplankton as one of her favorite ocean creatures, a sentiment reinforced by her conversation with biologist Martina Mascioni.

Regina Barber [00:14]: "One of my new favorites after talking with biologist Martina Mascioni is phytoplankton."

Martina Mascioni emphasizes the foundational role of phytoplankton in oceanic food webs:

Martina Mascioni [00:34]: "They're the base of the food web in most of the ocean areas and like our earth is like 70% ocean. So everything that happens in the ocean relies on phytoplankton eventually."

Phytoplankton, deriving from the Greek word for "drifter," are microscopic organisms that cannot swim against currents. Unlike jellyfish, phytoplankton are capable of photosynthesis, converting sunlight into energy, which not only sustains marine life but also contributes significantly to Earth's oxygen supply.

Martina Mascioni [01:09]: "There are some estimations that say like 50% of the oxygen that is on the atmosphere has come from the ocean and specifically from the phytoplankton."

The Antarctic Polar Fjords

Martina Mascioni's research focuses on phytoplankton residing in Antarctic polar fjords—narrow ocean inlets sculpted by glaciers. These fjords are characterized by crystal-clear waters rich in nutrients such as nitrates, phosphates, and sulfur, creating an abundant environment for phytoplankton.

Regina Barber [01:23]: "Martina studies phytoplankton that live in Antarctic polar fjords, these narrow ocean inlets that have been carved out by glaciers because of the crystal clear water and the abundance of nutrients like nitrates, phosphates, and sulfur."

During the Antarctic summer, an abundance of phytoplankton supports millions of tons of krill, which in turn sustain migrating whales and other marine life. Martina describes these communities as "very productive" and "very diverse."

Martina Mascioni [01:49]: "So it's very, very productive community, and it's also very diverse."

The Fjord Fido Community Science Project

To monitor changes in phytoplankton populations, Martina participates in the Fjord Fido Project, a community science initiative that leverages the involvement of tourists and tour operators in Antarctica. This project aims to assess the impacts of climate change on the ocean's foundational food web by collecting continuous data across different seasons and years.

Regina Barber [01:54]: "But new research Martina is doing as part of a community science program called Fjord Fido suggests that balance may be shifting."

Research Methodology: Engaging Tourists in Science

The Fjord Fido Project collaborates with tour vessels operating in Antarctica's Southern Hemisphere summer months (November to March). Tourists onboard these vessels are trained to collect water samples at designated sites using specialized kits provided by the project.

Martina Mascioni [05:46]: "So what we do is train those two guys that are going to be with different passengers to run the program with their own boats."

Participants embark on inflatable boats equipped with sampling instruments and bottles to collect data from various GPS-marked locations. This citizen science approach not only expands the data pool but also engages the public in meaningful scientific research.

Martina Mascioni [06:10]: "And so they kind of like have a list of samples and data that they have to gather when they are there."

Continuous Data Collection and Insights

Traditional research vessels often provide limited temporal coverage, capturing data snapshots that may not accurately reflect long-term trends. In contrast, the Fjord Fido Project's partnership with passenger ships facilitates more continuous and comprehensive data collection.

Martina Mascioni [07:55]: "When you go with a research vessel, sometimes you go like a month or like two weeks or very short periods of time."

Through this sustained data collection, scientists can better understand seasonal variations and year-over-year changes in phytoplankton populations.

Martina Mascioni [08:48]: "So how regular people are fueling research on some of the tiniest, most influential critters on Earth and how the shifting balance of power could ripple across the entire ocean."

Phytoplankton Blooms and Their Detection

Phytoplankton populations can experience explosive growth known as blooms, which can sometimes be visible from space due to color changes in the water. Martina reports that the Fjord Fido Project has recorded numerous blooms, varying in frequency and diversity across different years.

Martina Mascioni [10:18]: "So yeah, we have been looking at the samples and finding a lot of different blooms in the different years. Some years with, like, more Blooms or, like, diverse blooms and some with less phytoplankton."

These blooms are indicative of favorable conditions—such as optimal temperatures and nutrient availability—that allow phytoplankton to proliferate rapidly.

Impacts of Phytoplankton Decline on the Ecosystem

A significant decline in phytoplankton populations would have cascading effects on the Antarctic food web. Krill, a small crustacean resembling shrimp, depend on specific phytoplankton like larger diatoms for food. A reduction in these phytoplankton would force krill to seek alternative food sources, jeopardizing the survival of predators such as whales and penguins.

Martina Mascioni [11:39]: "Everything kind of relies on krill. Krill is this little crustacean. It kind of looks like shrimp. And it's what we sometimes hear about, like, oh, what whales eat."

Martina underscores the uncertainty surrounding future phytoplankton trends, noting that shifts in species composition could also disrupt ecological balances.

Martina Mascioni [11:39]: "So everything kind of relies on krill, and krill relies on a specific group of phytoplankton, which are the larger diatoms. So what happens if the diatoms are not there anymore? They will have to look for other food, and that would have, like, a major impact on the rest of the ecosystem."

Urgency in Understanding Antarctic Phytoplankton

Martina emphasizes the critical need to study Antarctic phytoplankton before environmental changes render these ecosystems fragile or lost. She highlights the potential for discovering novel biological compounds and the importance of preserving the unique adaptations of Antarctic organisms.

Martina Mascioni [12:52]: "I feel like the time is now to understand these places before, like, they change or they're gone. A lot of things that could be super cool happening, and we have no idea."

Conclusion

The episode concludes with a reflection on the interconnectedness of phytoplankton and the broader marine ecosystem, urging continued research and public engagement to safeguard these vital oceanic foundations.

Regina Barber [13:41]: "It's a very optimistic thought. Martina, thank you so much for talking with me today."

Listeners are encouraged to learn more about the Fjord Fido Project through the episode notes and to stay updated by following Short Wave on their preferred podcast platforms.

Credits:
Produced by Burleigh McCoy
Edited by Rebecca Ray Ramirez
Fact-checked by Tyler Jones
Audio Engineer: Jimmy Keeley
Senior Director: Beth Donovan
Senior VP of Podcasting Strategy: Colin Campbell