LEOPARD FROG CONSERVATION
TESF biologist, Hanne Small, tells Beau Turner about Chiricahua leopard frog conservation work on the Ladder Ranch in New Mexico.
(1) Maintaining healthy wild populations on the Ladder Ranch
(2) Creating captive refugia for threatened populations from across the range of Chiricahua leopard frogs
(3) Maintaining a Ranarium and tadpole-rearing facility on the Ladder Ranch for the purpose of captive breeding and repatriation of threatened populations from across New Mexico
FROGS ON THE LADDER RANCH & ESTABLISHING CAPTIVE
The Chiricahua leopard frog (CLF; Lithobates chiricahuensis) has disappeared from significant portions of its historical range in New Mexico and Arizona, and was listed as threatened under the Endangered Species Act in 2002. In keeping with the global phenomenon of amphibian population declines, multiple factors are implicated in the loss of CLF in the southwestern U.S., including disease, climate change, contaminants, habitat loss, and non-native invaders.
Just prior to listing, we initiated a monitoring program to establish the distribution and relative abundance of Chirichua leopard frogs (Lithobates chiricahuensis) on the Ladder Ranch. It has been ascertained that the Seco Creek drainage on the Ladder is home to the last large population of Chiricahua leopard frogs in New Mexico, and integral to the success of this population is their use of a connected network of stock-water tanks that provide a reliable source of perennial wetland habitat within this drainage.
We are seeking to emulate the successful Seco Creek population by modifying the stock-tank infrastructure in other drainages on the ranch in a way that can simultaneously support a commercial bison operation as well as contributing to the conservation of imperiled Chiricahua leopard frogs (see proposed tank augmentation).
In addition to expanding the range of CLF on the Ladder Ranch, we are working with the USFWS to modify steel stock tanks to create a network of captive Refugia tanks for frogs from across New Mexico. The use of these tanks stems from the observation that CLF naturally colonize these structures in areas where natural wetlands have been fragmented and lost. We are evaluating whether these structures can serve as viable assurance populations until these individuals or their offspring can be repatriated to the wild. We provision these tanks with floating vegetation and island habitats in an attempt to provide habitat for all frog life stages.
RANARIUM & TADPOLE REARING FACILITY
is currently developing the capacity to bring frogs into a
controlled captive environment with the overall goal of
captivebreeding and releasing large numbers of offspring
back into the wild. To this end, we have built a
Ranarium on the Ladder Ranck which can hold frogs from up to
8 different locations. In summer 2011, captive
Ranarium frogs successfully bred, producing large numbers of
tadpoles for release. In 2012, we plan to expand this
aspect of our CLF conservation strategy by building a tadpole
rearing facility adjoining the Ranarium that will be
used to rear tadpoles to a later stage before release.