Behavioral, Physiological and Genetic Adaptations to Urban Life in White Ibises
From Crustaceans to Carbohydrates: How White Ibises Adapt to Urban Diets
Florida is losing its natural wetlands at a fast rate. Marshes, swamps and peatlands are being converted into suburbs and arable lands, supporting the state’s growing economy and increasing population. These anthropogenic pressures threaten local wildlife as their natural habitats shrink and decrease in quality. Yet, one cannot visit Florida without noticing the large flocks of native White Ibises roaming through parks, golf courses and residential lawns. Once described as nomadic, carnivorous, wetland specialist, today’s urban White Ibises defy expectations and thrive in human-dominated landscapes. There, they have woven tight relationships with local residents, and replaced their protein-rich prey with carbohydrate-heavy human handouts. This urban diet is very different from what they have evolved with: continuously abundant and highly predictable, it is also composed of seeds and items intended for human consumption which may be difficult to recognize as food for a wetland carnivore. Yet, we do not have any evidence that this urban lifestyle negatively impacts White Ibis health, which suggests that they are well adapted to this diet. My aim for this project is to characterize how urban ibises adapt to their novel urban diet at three complementary levels: behavioral, physiological and genetic.
1) Behavioral adaptation: innovation. Urban dwellers must be able innovate in order to recognize and exploit novel anthropogenic resources. Thus, I propose that well-adapted urban ibises are successful on our lawns because of high innovation capacities. I will quantify innovation by exposing urban and wetland flocks to a custom-designed automated puzzle box.
Altered movement and social structure. With the help of many dedicated community scientists, I am collecting data on where and when ibises go, with whom and to do what. With this, I will be able to characterize the social structure, movement and behavior of urban White Ibises, to understand more about their life in our cities.
2) Physiological adaptation: amylase activity. I will evaluate urban ibises’ capacity to digest starchy food items by measuring the activity of pancreatic and salivary amylase in urban and non-urban ibises.
3) Genetic adaptation: amylase genes family. I will look for genetic divergence and evidence of selective pressures in the amylase genes family between urban and non-urban ibises to see if potential enzymatic adaptations are due to flexibility or rapid genetic divergence between urban and non-urban ibises.
Significance of the project
This project investigates how white ibises can help us understand the behavioral and genetic consequences of urbanization, and how our changing landscapes and cultures shape evolution. As a keystone species in both Florida’s wetlands and cities, the White Ibis offers a rare lens into long-term human-wildlife coevolution in the Everglades, a system that has never existed outside of human management.
My research integrates behavioral experiments, genomics, and citizen science to address three goals: (1) determine whether urban ibises are undergoing genetic changes in genes related to starch digestion due to their carbohydrate-rich urban diets; (2) test whether urban ibises are more innovative than their wild counterparts using a standardized puzzle-box feeder; and (3) explore how long-standing cultural relationships with this bird, from Indigenous stewardship to modern urban feeding behaviors, can help build community-centered models for conservation via an on-going citizen science project. Each of these goals paint a more complete picture of how species adapt to human-dominated landscapes and how humans, in turn, respond to wildlife.
While urban genetic adaptation is an established field, the role of diet-specific selective pressures remains underexplored. Yet, genes related to starch digestion often evolve rapidly in avian species, making them ideal for studying how quickly urban lifestyles can leave a genomic signature. Genetic divergence occurring between urban and wetland ibises, may have significant conservation implications: traits that help ibises thrive in cities might reduce their fitness in natural wetlands, potentially leading to reduced gene flow, ecological isolation, and even incipient speciation.
My behavioral component addresses an urban ecology challenge: predicting which species will adapt to urbanization and which will not. The White Ibis presents an unusual case. Once considered a wetland specialist it currently thrives in cities, unlike any other Everglades wading bird, despite similar life history traits. My experimental design overcomes common biases by using automated puzzle feeders, which provide equal exposure to innovation opportunities for urban and non-urban birds without requiring human presence. This method allows for cleaner comparisons and better insights into innovation, critical to adapt to rapidly changing environments. Additionally, conservation is typically observational, thus my experimental approach is unique in this field. Applied to other birds, it could help identify species that will not be able to relocate when their habitats are shrinking.
This project proposes a collaborative, community-centered approach to conservation. Through citizen science, local residents help monitor ibis behavior and movement. These contributions have already led to the documentation of novel foraging behaviors and long-distance tracking. Importantly, participants report a deeper connection to urban wildlife, particularly to an iconic bird they already know and recognize.
This project will help establish a new research direction, grounded in the empirical study of human-wildlife coevolution. By positioning the White Ibis as both an ecological and cultural keystone, I propose that some species remain central to our shifting ecosystems because they co-evolve with us and the changes we make to our landscapes. Understanding these relationships opens groundbreaking avenues for conservation and evolutionary science in the Anthropocene.
Community engagement
This project will positively impact several groups in South Florida, beginning with the communities who share their neighborhoods and parks with the White Ibis. Through my citizen science program, local residents become active participants in scientific discovery and learning how their everyday interactions with ibises are shaping wildlife behavior and evolution. Empowering people to see themselves as part of a dynamic ecological system, the project fosters environmental awareness and connection to native biodiversity.
Participants already report stronger bonds with the ibis after engaging in the project. Some have shared that they had always seen the ibis but never truly noticed it until they were invited to observe its behavior. People are already enthusiastic and exchanging about the ibises on the project’s social media, and extending its scope will spread the enthusiasm around wildlife to new communities. Because I conduct fieldwork in public parks I often interact directly with the public, answering questions and giving impromptu ornithology lessons to curious kids and their families. These everyday moments transform public parks into living classrooms.