SPECIES ASSESSMENT FOR COLUMBIA SPOTTED FROG (RANA LUTEIVENTRIS ) IN WYOMING prepared by 1 2 DEBRA A. PATLA AND DOUGLAS A. KEINATH with support from Mathew McGee 2 and David S. Pilliod 3 1 Herpetology Laboratory, Dept. of Biological Sciences, Idaho State University, Pocatello, ID 2 Wyoming Natural Diversity Database, University of Wyoming, 1000 E. University Ave., Dept. 3381, Laramie, WY 3Dept. of Biological Sciences, College of Science and Math, California Polytechnic State University, San Luis Obispo, CA prepared for United States Department of the Interior Bureau of Land Management Wyoming State Office Cheyenne, Wyoming January 2005 Patla and Keinath – Rana luteiventris January 2005 Table of Contents SUMMARY .................................................................................................................................... 4 INTRODUCTION ............................................................................................................................ 5 NATURAL HISTORY ..................................................................................................................... 6 MORPHOLOGICAL DESCRIPTION ........................................................................................... 6 Juveniles and Adults.................................................................................................................. 6 Tadpoles .................................................................................................................................... 7 Eggs........................................................................................................................................... 8 TAXONOMY AND DISTRIBUTION ............................................................................................ 8 Taxonomy.................................................................................................................................. 8 Distribution and Abundance.................................................................................................... 10 Population Trends.................................................................................................................... 13 HABITAT REQUIREMENTS ....................................................................................................15 General .................................................................................................................................... 15 Breeding and larval habitat...................................................................................................... 17 Foraging habitat....................................................................................................................... 19 Winter habitat.......................................................................................................................... 20 Area Requirements.................................................................................................................. 21 Landscape Context .................................................................................................................. 22 MOVEMENT AND ACTIVITY PATTERNS ..................................................................................24 Emergence and early-season movements................................................................................ 25 Summer ................................................................................................................................... 26 Late summer and movements to winter habitats ..................................................................... 28 Winter...................................................................................................................................... 29 Site Fidelity ............................................................................................................................. 30 Inferred Connectivity .............................................................................................................. 30 REPRODUCTION AND SURVIVORSHIP ...................................................................................31 POPULATION DEMOGRAPHICS .............................................................................................34 Summary ................................................................................................................................. 34 Fecundity and Larval Survivorship ......................................................................................... 34 Age at First Reproduction ....................................................................................................... 36 Proportion of the Population Breeding.................................................................................... 36 Post-metamorphic Survivorship and Longevity...................................................................... 37 Spatial Characteristics and Metapopulations........................................................................... 38 Genetic Concerns .................................................................................................................... 41 FOOD HABITS ....................................................................................................................43 COMMUNITY ECOLOGY .......................................................................................................45 Predators.................................................................................................................................. 45 Competitors ............................................................................................................................. 47 Parasites................................................................................................................................... 49 Disease .................................................................................................................................... 50 Interactions.............................................................................................................................. 52 CONSERVATION ......................................................................................................................... 53 CONSERVATION STATUS .....................................................................................................53 Federal Endangered Species Act............................................................................................. 53 Federal Land Management Agencies ...................................................................................... 54 Page 1 of 123 Patla and Keinath – Rana luteiventris January 2005 State Wildlife Agencies........................................................................................................... 54 Natural Heritage Programs...................................................................................................... 54 BIOLOGICAL CONSERVATION ISSUES ...................................................................................55 Extrinsic Threats and Reasons for Decline ............................................................................. 55 Livestock Grazing............................................................................................................. 57 Water manipulation........................................................................................................... 58 Roads ................................................................................................................................ 59 Introduced fish.................................................................................................................. 60 Disease.............................................................................................................................. 62 Drought and climate change ............................................................................................. 63 Fire.................................................................................................................................... 66 Timber Harvest and Fuel Reduction................................................................................. 68 Beaver reduction or eradication........................................................................................ 69 Pesticides, Herbicides, and Environmental Contaminants................................................ 70 Oil/Gas Development and Mining.................................................................................... 73 Recreation......................................................................................................................... 75 Other potential threats....................................................................................................... 75 Trend Information ................................................................................................................... 77 Intrinsic Vulnerability ............................................................................................................. 78 CONSERVATION ACTION ........................................................................................................... 80 EXISTING OR FUTURE CONSERVATION PLANS ......................................................................80 CONSERVATION ELEMENTS ................................................................................................81 Management Approaches.......................................................................................................