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Call for Citizen Scientists! Help USGS and Partners Monitor Diamondback Terrapins

USGS scientists and partners are turning to citizen scientists in the Florida Panhandle to help provide the information that is needed to better understand the only turtle species that lives in brackish environments.

Diamondback terrapin in marsh grass
Diamondback terrapin in marsh grass in Florida Panhandle

What is a diamondback terrapin?

The diamondback terrapin (Malaclemys terrapin) is a coastal turtle species that ranges along the U.S. coast from Massachusetts to Texas. As the only turtle species to live in brackish water (a mix of salt and fresh water), Diamondback terrapins are typically found in habitats, such as salt marshes, mangroves, estuaries, and bays. Seven genetically distinct subspecies of terrapins have been described throughout the range. Terrapins are sexually dimorphic, meaning the sexes display different characteristics, with females reaching larger adult sizes than males. In addition to snails, terrapins rely upon a varied diet that includes insects, fishes, and crabs.


Threats facing terrapins:

  • Habitat loss from human development in coastal areas
  • Collection in the pet trade
  • Bycatch in crab traps
    • As a turtle species, they require air to breath and when caught in crab traps they are unable to reach the surface and drown.


Why is USGS interested in the species?

Diamondback terrapin tracks on sand
Diamondback terrapin tracks on sand at a nesting location in the Florida Panhandle.

Diamondback terrapins have been studied in many parts of their range, but the Florida Panhandle has long been an area where few data are available. As a result, very little is known about the life history of this species in the region. Florida currently does not list any terrapin subspecies or population in the state as threatened or endangered. However, Florida has recently enacted measures to eliminate take from the wild.

Terrapins are still an important species to monitor as they are at risk due to continued development of coastal areas that may result in habitat loss and mortality. They play an important role in maintaining brackish water habitats by foraging on snails that have the potential to overgraze estuarine vegetation. Two of the seven terrapin subspecies inhabit the Florida Panhandle, the Ornate (M. t. macrospilota) and Mississippi (M. t. pileata). USGS researchers have the opportunity to learn more about the species in the region to increase awareness and inform management decisions.

History of the Panhandle Terrapin Project

This project began in 2005 with the objective of determining whether terrapins even existed in the Panhandle. The team placed “Wanted Posters” at boat ramps in locations with suitable habitat. In 2007, surveys began at sites that were identified by the poster effort. Volunteers were able to verify at least one record of a terrapin in each of the Panhandle counties. This was followed by nesting surveys and 30-minute head counts to determine relative abundance. 

Current activities of the Panhandle Terrapin Project

USGS researchers, partnering with Florida Sea Grant as well as other local and state agencies, have initiated a citizen science effort to help locate terrapins, identify the habitats they use and monitor nesting activity. With this cooperative effort, researchers and citizen scientists can begin to fill the gaps in our understanding of terrapins in the Florida Panhandle region.

A diamondback terrapin is held up into a green and gray tag reader.
A scientist reads a PIT (passive integrated transponder) tag in a diamondback terrapin in the Florida Panhandle.


How you can help!

Send us terrapin sightings!

Terrapins can be found in brackish water habitats such as salt marshes, bays, or water bodies adjacent to salt water. Being in one of these habitats is step one in figuring out if the turtle you are seeing is in fact a terrapin. If you do find one:

  1. Safely take a photo of the terrapin
    1. No need to handle them for a picture
  2. Record the GPS coordinates, which can be done from your phone’s map OR send us a specific location description
  3. Email those to USGS Biologist Daniel Catizone (, or any of the below listed contacts on this page.

If you are unsure if you are seeing a terrapin, it is always better to send a picture to be safe!


The project is also currently accepting volunteers throughout the Florida Panhandle region.

  • Volunteer opportunities are available from April to October, broken up into two primary survey seasons: nesting and hatching.
  • Volunteers must be able to
    • Devote a few hours a week for up to 12 weeks.
    • Work outside in the heat and/or inclement weather.
    • Navigate through shallow water and uneven, marshy and, in some cases, muddy terrain.
  • Training will be provided to active volunteers and will include how to collect data on terrapin sightings and nesting sites.
  • Volunteers will have the opportunity to assist biologists and trained personnel in the field as they take measurement data on terrapins, such as their shell length and width.
  • Other volunteer activities may be available, so for those individuals who are interested but not able to commit to one of the above listed requirements, please contact Daniel Catizone or Richard O’Connor for more information.
Diamondback terrapin
Diamondback terrapin (Malaclemys terrapin)