Bridging movement ecology and public health through One Health
10,000 years ago, humans and domesticated animals made up around five percent of vertebrates. The other 95 percent was composed of every other vertebrate. Today, this statistic is flipped, with a massive 95 percent made up of humans and our domesticated animals. A significant global shift was experienced during the Industrial Revolution, which some scholars mark as the start of the Anthropocene.
The Anthropocene is a proposed epoch dating from the start of significant human impact on the planet’s ecosystem. Within this epoch, which we are currently still in, human activity has significantly altered human population distribution among urban and rural centers. The current global population is about 8 billion people, which makes up only 0.01 percent of all living beings, yet is the most significant player in the direction of planetary narratives.
The stories of our planet are best understood through work in the field of One Health– the interconnectedness of environmental, animal, and human health. One Health has highlighted that each organism inevitably impacts the health of another, forming an intricate "web of life." Humans are not an exception. Increased urbanization has led to greater human-animal contact, which we can see through our work in Forest Park. This relationship between human and non-human animals holds implications for ecological relationships, environmental consciousness, and public health.
While certain urbanization trends pose a significant threat to many species, they can also provide opportunities for some, such as “urban adapters,” to thrive. Mammal urban adapters, such as raccoons and opossums, are capable of exploiting both human subsidies and natural resources. Raccoons stand out as exceptionally proficient at exploiting anthropogenic resources. The raccoon (Procyon lotor) has been reported to have occupied urban areas over 100 years ago.
To understand raccoon livelihoods in urban land, we studied their movement patterns in Forest Park, one of the largest urban parks in the United States. To collect movement data, we attached GPS collars programmed to collect acceleration data and GPS fixes at set intervals. Interestingly, we found them crossing interstates, spending time around neighborhoods, and moving great lengths in Kennedy Forest and beyond. Ultimately, our study highlighted the impacts of both natural and anthropogenic factors on urban wildlife behavior and how city life affects space use and movement.
Figure 1: Raccoon movement outside of Kennedy Forest and in neighborhoods, picnic pavilions, roads, and some recreational areas in Forest Park
Documenting animal movement patterns, as depicted in the figure, holds implications for and raises questions about the health of the species itself, other species, and importantly, the health of humans. Are raccoons prone to car accidents? Is the human food they eat healthy for them? How close are raccoons to humans? In which zip codes do we see the most raccoon activity?
Increased animal contact with humans leads to a greater potential for zoonotic disease transmission. Zoonotic diseases are those spread and shared between people and animals. 75% of emerging infectious diseases in humans are zoonotic. Following the movement of these animals allows researchers to track exactly where certain parasites may be present, providing clues to which human populations are more likely to be affected and what environmental factors could be contributing.
Raccoon team, Sara Parikh and Megan O' Shea, tracking raccoons via radio telemetry.
Understanding how pathogens are transmitted in raccoons, and other host animals, is important for devising effective management and disease prevention strategies. Movement ecology techniques and analysis can give insight into where an animal, thus potential environmental hazard may be located, and how this impacts humans and other species. Such attention to animal movement and behvior can also work towards predicting and preventing future threatening events, such as a pandemic.
For many, their calling to human medicine lies in it’s investigative aspect, where solving a medical case is like solving a complex puzzle. Each patient’s unique story is intricately woven by their culture and environment, bearing the benefits and burdens of the social determinants of health, all intimately tied to their quality of health. However, medicine and public health, until recently, are still missing a piece– the integrated stories of environmental and non-human animal ecology, which are also determinants of human health.
“Environment” in medicine should be observed beyond the social and into the physical. This is where the field of One Health emerges. As medicine is an interdisciplinary field, evolving human health concerns are closely linked to the health of the land and animals. Careful monitoring of environmental dynamics, such as the presence of toxins in specific demographics or behaviors of sentinel species, can offer crucial insights into predicting epidemiological outcomes. A physician with an understanding in One Health would then treat their patients with this in mind, thus delivering more holistic and informed care. For example, when treating a patient with lead poisoning, the prescription would not only be to provide medication, but to also remove any lead-containing paint in the household.
BeReal (social media app) selfie while raccoon tracking at night!
Animals play a significant role in providing us with indicators of declining environmental health and increased disease threats for all life, including humans. The stories of the environment, animals, and humans must be heard to best care for human patients. Humans are not independent of nature, but rather deeply connected to and a part of it. As a result, our actions directly impact planetary health, which ultimately impacts human health. The spread of zoonotic disease, food insecurity, environmental racism, and more, can be attributed to the effects of human activity on the planet. This reveals a cyclic relationship between the health of humans, animals, and the environment– the One Health triad. A relationship which may be better understood through the study of movement ecology.
One Health is quickly gaining traction and recognition in the public health sphere, as it provides a response to global health crises fomented by human actions in the Anthropocene. To optimize the health of all and build an environment that will sustain all, we need to rethink our fundamental values in approaching health. This renewed approach calls for human health to pay attention to animal and environmental health. This transdisciplinary approach to health would include findings in movement ecology, as humans, animals, and the environment share a narrative which impacts the health of each player. Our raccoons, along with the various other animals studied by the Forest Park Living Lab, are important figures in the One Health triad. Our research, educational initiatives, and diverse team unite to tell the vibrant stories of Saint Louis' rich ecology and advocate for environmental awareness.
By: Saint Louis University undergraduate student Sara Parikh.