COLLABORATIVE CONSERVATION EFFORT HELPS KEEP NEVADA'S COLUMBIA SPOTTED FROG McAdoo, Natural Resources Specialist, Cooperative Extension FROM FEDERAL LIST- Kent Chad Mellison, Biologist, U.S. Fish & Wildlife Service Rangeland Scientist, Great Basin Rangelands Research Unit, US Department of Agriculture, Agricultural Research Service, 920 Valley Road Reno, NV 89512 charlie.clements@ars.usda.gov Habitat Supervisory Biologist and Supervisory Wildlife Biologist, Nevada Department of Wildlife, Vice President, Elko Land and Livestock, and Agricultural Research Science Technician, US Department of Agriculture, Agricultural Research Service
INTRODUCTION
another cannot occur. Reduction in spotted frog distribution Species Description and Life History has apparently been associated with So what’s a “spotted frog, anyway? The impacts from water developments and the Columbia spotted frog (Rana luteiventris) introduction of nonnative fish and amphibbelongs to the anuran family of true frogs, ian predators. Other specific threats to the or Ranidae. Frogs in this widely distributed frog include improper livestock grazing, family are smooth, moist-skinned, and have spring development, mining, over-harvest large powerful hind legs. There are only of beaver, disease, and climate change. three other true frogs native to Nevada: the northern leopard frog (Lithobates pipiens), relict leopard frog (Lithobates onca), and HISTORY OF ENDANGERED Sierra Nevada yellow-legged frog (Rana SPECIES ACT STATUS sierrae). Two additional frog species have In 1989, the U.S. Fish and Wildlife Serbeen successfully introduced into Nevada, vice (FWS) was petitioned to list the spotted the red-legged frog (Rana aurora) native frog (referred to originally as Rana pretiosa) to California and the bullfrog (Lithobates under the Endangered Species Act of 1973, catesbeianus) from east of the Rockies. as amended. The FWS ruled on April 23, Columbia spotted frogs are slim1993, that listing of the spotted frog was waisted and long-legged amphibians with warranted and designated the species as a webbed hind feet. Adults are from two to candidate for listing. In 1997, after speciesColumbia spotted frogs have benefitted from collaborative conservation. four inches in length (snout to vent), with specific genetic and geographic differences This species was removed from consideration for federal listing females being larger than males. The dorsal confirmed a Great Basin distinct populalargely because of successful cooperative efforts. (upper side or back) color of these frogs tion segment (DPS), the FWS conferred a (Photo courtesy of Teri Slatauski, Nevada Department of Wildlife). ranges from light brown, dark brown, or high priority designation (Priority 3) for the gray, with small spots (Figure 1). Ventral Great Basin population. However, the frog (underside or abdominal) coloration differs geographically, ranging from yellow to was precluded from listing due to higher priority species like the greater sage-grouse. salmon (Figure 2), but very young individuals may have nearly white ventral surfaces. The major impetus behind the petition was the reduction in distribution apparThe range of this species extends throughout the Great Basin, northern Rocky ently associated with the threats mentioned above. This ranking category included Mountains, British Columbia, and southeast Alaska. However, genetic research in- Great Basin Columbia spotted frog populations in both northeastern Nevada and dicates that frogs in southeastern Oregon, southwestern Idaho, and northeastern and the Toiyabe Range in central Nevada. In its December 6, 2007 Candidate Notice of central Nevada are a distinct population. Review, the FWS announced a change in priority for the Great Basin spotted frog In Nevada, Columbia spotted frogs are found closely associated with slow-moving populations from Category 3 to Category 9, and this determination was maintained or ponded surface waters that are clear and have little or no vegetation canopy cover. in subsequent years. [Note: The only other Columbia spotted frog populations in Habitats of viable populations typically include springs, often with floating vegeta- Nevada are located in the eastern portion of White Pine County near the Nevada/ tion, and larger bodies of pooled water (including oxbows, lakes, stock ponds, beaver Utah border and are geographically and genetically associated with the West Desert ponds, seeps in wet meadows, and backwaters). The frogs apparently require a deep population in Utah – these populations were withdrawn from federal candidate status silt or muck substrate for hibernation and torpor (a state of decreased physiological in April 1998.] activity, including a reduced body temperature and metabolic rate). Females may lay COLLABORATION HISTORY only one egg mass per year, with extreme yearly fluctuations in egg mass size. SuccessFrom 1999-2002, a Columbia Spotted Frog Technical Team, comprised of several ful egg production, viability, and metamorphosis of spotted frogs are influenced by cooperating entities including the FWS, Nevada Department of Wildlife, Bureau of habitat variables such as temperature, depth, and pH of water, cover, and the presence Land Management, US Forest Service, Nevada Natural Heritage Program, Natural or absence of predators (especially fish and bullfrogs). Resources Conservation Service, Nye County, and University of Nevada Cooperative Threats to Spotted Frogs Extension worked together to write a conservation plan for this species. Upon signaIn the Great Basin, Columbia spotted frogs are found in naturally fragmented habitats that are often seasonally dry and resource-limited. Such habitats are sensitive ture approval in 2003 by these same entities, a 10-year Conservation Agreement and to disturbance, both natural and human-caused, thus increasing the chance of local Strategy (CAS) was written for each of the affected Nevada spotted frog population extirpation for its inhabitants. The elimination, fragmentation, and/or degradation segments (Northeast Nevada and Toiyabe subpopulations). During this time (2003of any use area (e.g., adult foraging range, winter hibernaculum, breeding pool) will 2013), a Technical Team for each CAS was charged with plan implementation, evaluhave a negative effect on local populations because of the wide use of riparian areas by ation, and strategy revision as necessary. Survey and monitoring activities by these adult frogs. These effects on metapopulations may result in widespread declines. If cor- teams were designed to increase knowledge of spotted frog distribution, populations, ridors between population units are eliminated, dispersal from one population unit to and habitat. 34 November-December 2016
The Progressive Rancher
www.progressiverancher.com