What's Inside a Burmese Python? A Scientist Studies the Everglades' Invader

Christina Romagosa studies what is inside invasive Burmese pythons to learn how they affect the wildlife of Everglades National Park. NPS photo by R. Cammauf.

Christina Romagosa, a research associate professor in the University of Florida's Department of Wildlife Ecology and Conservation, studies how ecosystems respond to invasive species, non-native species that cause harm. Much of her work is in South Florida, and some of it concerns the invasive Burmese pythons of Everglades National Park, especially what is inside them. Antonia Florio, the park's science communications liaison, talked with her about her research and her path into science.

Growing up with invaders

Raised in South Florida, Romagosa loved the birds and reptiles of her back yard, and noticed as a child that the brown anoles around her house and the monk parakeets at her elementary school were not native: the start of her interest in invasive species. Science appealed to her, but in college she met no well-known biologists who shared her background and felt somewhat alone, until she read an interview in her biology textbook with Ariel Lugo, a Puerto Rican ecologist. As a Cuban American who had never met a Latinx scientist successful in ecology, she found it deeply motivating, and with support from her parents and mentors she went on. She does not think of herself as a role model, but is delighted when students tell her that seeing someone of their background in the field makes them feel they can do it too.

Why pythons

Birds were her first love; she came to pythons through invasion ecology. The Everglades, special to her, has several invasive species, and understanding their effects matters especially for its restoration. The python is a top predator that can affect birds, mammals and some reptiles, and she wants to know how its presence changes the ecosystem.

What pythons eat

It was already known that pythons eat mostly mammals. Her team wanted to pin down which animal groups are most at risk, and whether a new predator is setting off trophic cascades, knock-on changes through the food web, and whether the diet varies by place and over time, questions made hard by how, when and where pythons have been caught.

Working with the U.S. Geological Survey and the National Park Service, she receives pythons caught in or near the park. USGS and park scientists perform necropsies and send gut samples to her lab, where she and student volunteers clean the contents and identify prey under the microscope from hair, teeth, feathers, bones and beaks; the Smithsonian's Carla Dove has identified most of the bird remains. DNA has not worked: USGS collaborators could not extract it from the lower gut, probably because acidic digestion destroys it.

In the southern Everglades, around Mahogany Hammock and Flamingo, pythons eat mainly rodents such as hispid cotton rats; elsewhere the lab has found opossums, wading birds, alligators and even an iguana. The full results were being prepared for publication.

A parasite that moved faster than its host

The pythons also brought a lung parasite native to Asia, the pentastome Raillietiella orientalis, which is more closely related to crustaceans than to parasitic worms. Romagosa's former graduate student Melissa Miller studied it for her dissertation, driving roads at night to collect dead native snakes and pythons and dissecting them. Their published results show that:

• the parasite infected 13 species of native Florida snakes;
• native snakes were infected more often than pythons, carried more parasites, and harboured larger female parasites;
• one snake held 77 of them, enough to affect breathing in heavily infected snakes;
• the parasite has turned up in native snakes where pythons have not yet reached, so native snakes are probably passing it among themselves: a parasite can spread faster than its original host.

Advice for young scientists

Her advice for success in research: build strong connections, such as by talking with and listening to scientists at conferences, listen, be trustworthy, and do good science.

More: her lab's page · invasive species in Everglades National Park · previous in the series: The First Recorded Python in Everglades National Park, 40 Years Later.

Sources

• Antonia Florio, Everglades National Park, "So What's in a Burmese Python Anyway?," National Park Service, Invasive Species in South Florida series. https://www.nps.gov/articles/000/so-what-s-in-a-burmese-python-anyway.htm
• Three photographs from the researchers are not reproduced here.
• Words on this page from people and organisations outside the federal government are paraphrased; rewritten in hubnx's own words.