Checking PVC pipes for amphibians at Jean Lafitte National Historical Park and Preserve
Checking PVC pipes for amphibians at Jean Lafitte National Historical Park and Preserve

Photo credit: Chris Adams

The Gulf Coast is home to many amphibian species, and in fact, the region is near the top for amphibian species richness in the United States. Amphibians are a key vital sign for monitoring in Gulf Coast Network parks because

  1. Many amphibian species are geographically restricted, which means they are only found in a few locations.
  2. Some parks have specifically identified at-risk species in their management plan.
  3. Amphibians are good indicators of wider ecosystem change because they have semi-permeable skin and often have aquatic larval stages. This makes them highly sensitve to habitat change and particularly to changes in water quality.

The complete background, rationale and procedures for amphibian monitoring by the network are described in a protocol narrative and 8 standard operating procedure (SOP) documents. The protocol is titled "Monitoring Amphibians in Gulf Coast Network Parks". It was published in the NPS Natural Resource Report Series in late 2018, and it is available to the public on IRMA, following the links posted further below.

A summary of the vital sign and monitoring approach can also be found in the 2-page brief: Amphibian Monitoring Program Summary.

The Gulf Coast Network's approach to long-term monitoring of this vital sign focuses on a subset of amphibian species. To learn more about all amphibian species in network parks, see our park-specific inventory reports and species lists for amphibians and reptiles. We also have a short video about our amphibian monitoring protocol, which you can watch here.

Source: Data Store Saved Search 3495. To search for additional information, visit the Data Store.

Source: Data Store Saved Search 3494. To search for additional information, visit the Data Store.

Left image is a squirrel treefrog inside a PVC pipe, and right image is a green treefrog outside of the pipe
On the left, a squirrel treefrog inside a PVC pipe, as found during amphibian monitoring at Gulf Islands National Seashore. On the right, a green treefrog on the outside of the two PVC pipes during a pilot study at San Antonio Missions NHP.


six photos of treefrog species showing the underside of the rear leg, used in identification
Treefrogs with their hind leg extended, to show the femoral region used in IDing our five most-likely Hylid species. (A) Hyla versicolor/chrysoscelis is grey with a yellow mottled femoral patch; (B) H. avivoca is also grey but has a light green or grey mottled femoral area.  (C) H. femoralis has yellow spots on the femoral region. (D) H. cinerea has no femoral markings and the skin is white, transparent or cream; (E) and (F) H. squirella can be green or brown with yellowish femoral skin.


plywood coverboards lying on the ground, for amphibians to use as artificial refuges
Plywood coverboards being labeled in preparation for long-term deployment at San Antonio Missions National Historical Park.

Photo by Chris Adams

close-up of Gulf Coast Toad sitting on the ground
Gulf Coast Toad (Incilius nebulifer) uses coverboards as refuges in several Gulf Coast Network Parks

Jane Carlson/NPS

Last updated: November 10, 2023