Source: Duran, Michael C.2004. An Inventory of Reptiles and Amphibians of Padre Island National Seashore.Texas Conservation Data Center. The Nature Conservancy.
A New Frog for Padre!
For many years, Rangers at Padre Island National Seashore have been puzzled by the calls of a particularly elusive frog. Auditory calls, or vocalizations, are often recorded and used by scientists to identify species of hard to find amphibians. Many recordings were taken over the years of this particular frog in the park. As the frog continued to evade capture, multiple amphibian experts were consulted, however no one could make a definitive identification of the call. This mystery has eluded scientists for over a decade, until recently.
The summer months of 2015 were uncharacteristically rainy. The average annual rainfall for Padre Island National Seashore is approximately 32 inches; however in 2015 the park received over 53 inches. Frogs rely on freshwater for reproduction; rangers knew that the increase in surface water created a unique opportunity to study these amphibians. Additional frog vocalizations were recorded after rainstorms, but observing the frogs in the wild was still proving tricky. Finally on August 6, 2015, after years of painstaking work to capture and document these frogs, Park Ranger Alicia Walker finally spotted and was able to collect one of the mystery frogs.
The captured frog was identified as the Eastern Narrow-mouthed Toad. Experts were contacted to validate the identification of the frog because no historical records existed for the Eastern Narrow-mouthed Toad from Mustang Island, North Padre Island, South Padre Island, Nueces County, or any of the counties to the south. Narrow-mouthed Toads are very secretive, very small, and live mostly underground. They feed on a variety of insects but primarily eat ants. These elusive frogs breed on rainy summer nights where they congregate at temporary fishless water bodies. This is where rangers began trapping for more specimens, documenting every step of the process. After a month of trapping, 66 individuals were captured and confirmed as the Eastern Narrow-mouthed Toad.
Additional research is now needed to understand why the distribution has shifted so significantly. And further genetic research is needed to discover why the population at Padre Island National Seashore has such a unique call. Nonetheless, this is an exciting new discovery for Padre Island National Seashore.