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  • Leopard frog salvage after the Bighorn Fire

    Oct 02, 2020 | Read More News
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    Pima County and partner biologists from the U.S. Forest Service, Arizona Game and Fish Department, U.S. Fish and Wildlife Service, National Park Service, as well as citizen scientists, recently translocated 92 lowland leopard frogs from canyon streams on the east side of the Santa Catalina Mountains whose watersheds were burned in the recent Bighorn Fire. 

    The lowland leopard frog is one of the 44 plant and animal species that are covered by Pima County’s Multi-species Conservation Plan, and for which Pima County provides stewardship.  The lowland leopard frog, and many other species, benefit from the extensive open space lands that Pima County and the Pima County Regional Flood Control District own and manage.  In most cases, these open space lands are open to the public to recreate responsibly in, and enjoy our region’s fantastic variety of plant and animal life.


    During the recent Bighorn Fire in the Santa Catalina Mountains, biologists from a number of organizations, including Pima County, began discussing the threat that massive debris flows of ash and sediment could pose to sensitive aquatic species once rains returned to the burned watersheds. 

    Several Pima County properties whose upper watersheds were burned in the Bighorn Fire have sensitive perennial stream habitats that are home to ecologically important populations of lowland leopard frogs. Frog capture in Bullock Canyon

    A major risk that fires pose to these sites often comes up to several years following the fire, when heavy rainfall events may wash huge deposits of sediment off of slopes that have been denuded of vegetation and deposit this sediment miles downstream where it can fill in the pool and stream habitats that leopard frogs need to survive. Click here for more information on how fires may impact leopard frogs.

    The lowland leopard frog has experienced extensive population declines due to factors such as nonnative aquatic species like green sunfish and bullfrogs that eat them, as well as the loss of riparian habitat and mass mortality due to a widespread and infectious amphibian disease caused by the chytrid fungus, Batrachochytrium dendrobatidis.

    Some of the largest and most important populations of lowland leopard frog that are left in the Tucson area occur on Pima County lands in several canyons in the Catalinas. Subsequently, Pima County coordinated with the Arizona Game and Fish Department and the U.S. Forest Service to access three different canyon sites whose upper watersheds were all extensively burned in the Bighorn Fire, once conditions were safe to do so. 

    Biologists from Pima County, U.S. Fish and Wildlife Service, Arizona Game and Fish Department, National Park Service, as well as a citizen scientist made two different expeditions into Edgar, Buehman, and Bullock Canyons to capture and relocate leopard frogs to two different sites not susceptible to post-fire flooding.

    The goal is that frogs at these sites would thrive and reproduce and act as assurance colonies if sites in their home canyons were impacted by flooding and needed to be re-established at a later date. Both sites are nearby within or near the current range of lowland leopard frogs, and include a privately managed pond in Cascabel, AZ, and an earthen pond on Pima County’s Six Bar Ranch.

    Following well-tested protocols created by the Ranid Frogs Project of the Arizona Game and Fish Department, both expeditionsLeopard frogs in a bucket successfully moved 49 leopard frogs from Edgar Canyon on 12 July, and 43 leopard frogs from Buehman and Bullock Canyons on 15 July. 

    *Update*  Juvenile frogs released into the Cascabel pond have grown rapidly and as of mid-September 5-6 male leopard frogs have been chorusing and at least one egg mass has been laid in the pond.  Early indications are that this site has all the ingredients for successfully nurturing multiple generations of leopard frogs. 

    We acknowledge the Cascabel Conservation Association for their support of this pond site and Alex Binford-Walsh for monitoring and management of the site. Click here to listen to chorusing lowland leopard frogs recorded by Alex Binford-Walsh at this pond (be sure to turn the volume up).
    Releasing frogs