Chesapeake Bay Otter Alliance

Chesapeake Bay Otter Alliance

The Chesapeake Bay Otter Alliance is a group of scientists, educators, and community members who are working to find and learn about river otters throughout the Mid-Atlantic region. We want to better understand where otters are living and what they are doing there. We also want to study the kinds of parasites and diseases that otters have and if humans could become infected or sick by eating the same food or swimming in the water. By better understanding otters, we can better track changes in water quality threats to public health around the Bay!

Have you seen otters in your area? Fill out our survey!

Check out more about Katrina's lab and what they are learning from otters HERE.

The "What" and the "Why"


Water is fundamental for all life, but in many urban and suburban areas, waterways have been damaged by human impacts. Many of these rivers and coastal areas are plagued by toxins, pollutants, and trash, which can negatively impact human health, local economies, and harm precious wildlife. Monitoring water quality for a wide range of pollutants and pathogens is beyond the capacity of most communities and researchers.

Instead, scientists look for sentinel species, which are animals that are used to monitor environmental conditions. Often, they are sensitive to negative environmental conditions and can be infected by the same parasites as humans. Tracking these sentinel animals is generally easier than making lots of water quality measurements and can often provide lots of information about the health of the environment. The Chesapeake Bay Otter Alliance is developing a program to use river otters as sentinels of water quality and ecosystem health in the Mid-Atlantic region.

River otters are sensitive to toxins like mercury and PCBs, which are also harmful to human health. The presence of otters in rivers and coastal areas is generally a sign of good water quality and healthy waterways. Additionally, river otters eat many of the same seafood species that people do, including oysters, clams, white perch, and shad. By studying what the river otters eat within our local waters, we can learn what parasites, pathogens, and pollutants these food sources might be carrying that not only impact the river otters but could also be harmful for people.

Help us track river otter sightings! Because our research team can’t be everywhere at once, we want to engage with volunteers and communities to help map and learn about river otters. Volunteers can help by reporting river otters that they see. We are also working with school groups to study river otter diets and look for parasites. We’ll be able to share results from the project to help communities know more about the health of their local waterways and potential public health risks. 

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Citizen Science

Get Involved

Have you seen otters in your area? Fill out our survey below!

Our research team can’t be everywhere at once so we want to engage with volunteers and communities to help map and learn about river otters. Please fill out the survey below if you've seen evidence or sightings of river otters in your area! If you are unsure, view our field guide to see examples of scat and footprints that otters leave behind. Thank you for your help!

If you have any questions about the survey, please reach out to

Our list is constantly growing and we are always looking for new partners!

Our alliance includes experts in mammalogy, parasite and disease ecology, fisheries and estuarine ecology, veterinary medicine, animal behavior, education, and citizen science from SERC, the Smithsonian’s National Zoological Park, the Smithsonian’s National Museum of Natural History, Montgomery College, the Anacostia Watershed Society, and private citizens. Our list is constantly growing and we are always looking for new partners! If you are interested in joining our alliance, please email Katrina Lohan at

Website Section
Citizen Science