USFWS Oregon Spotted Frog Biop
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Clerical errors corrected on pages 202, 214 on 10/23/17 TABLE OF CONTENTS INTRODUCTION ......................................................................................................................1 CONSULTATION HISTORY ....................................................................................................1 BIOLOGICAL OPINION ...........................................................................................................4 1.0 DESCRIPTION OF THE PROPOSED ACTION ..................................................................4 1.1 Background .......................................................................................................................4 1.2 Principal Components of the Proposed Action ...................................................................6 1.2.1 The OSF Proposal .......................................................................................................6 1.2.1.1 Crane Prairie Reservoir ........................................................................................7 1.2.1.2 Wickiup Reservoir ...............................................................................................8 1.2.1.3 Crescent Lake Reservoir .................................................................................... 10 1.2.1.4 Federal Contract Actions .................................................................................... 11 1.2.2 Monitoring Activities ................................................................................................ 11 1.2.3 Review of Operations and Maintenance (ROM) and Safety Evaluation of Existing Dams (SEED) Programs .................................................................................................... 12 1.2.3.1 Overview of the Examination Process ................................................................ 12 2.0 ANALYTICAL FRAMEWORK FOR THE JEOPARDY DETERMINATION ................... 18 2.1 Jeopardy Determination ................................................................................................... 18 2.2 Adverse Modification Determination ............................................................................... 19 3.0 STATUS OF THE SPECIES - OREGON SPOTTED FROG ............................................... 19 3.1 Listing Status ................................................................................................................... 19 3.2 Taxonomy........................................................................................................................ 19 3.3 Physical Description ........................................................................................................ 20 3.4 Life History ..................................................................................................................... 20 3.5 Habitat ............................................................................................................................. 21 3.6 Distribution ...................................................................................................................... 23 3.7 Population Dynamics ....................................................................................................... 24 3.8 Rangewide Threats .......................................................................................................... 26 3.9 Consulted-on Effects ........................................................................................................ 27 3.10 Rangewide Conservation Needs ..................................................................................... 29 4.0 STATUS OF OREGON SPOTTED FROG CRITICAL HABITAT ..................................... 30 4.1 Physical or Biological Features and Primary Constituent Elements .................................. 31 4.2 Special Management Considerations ................................................................................ 33 4.3 Consulted-on Effects to Oregon Spotted Frog Critical Habitat ......................................... 33 5.0 ENVIRONMENTAL BASELINE ....................................................................................... 34 5.1 Status of the Spotted Frog in the Upper Deschutes River Sub-basin ................................. 38 5.1.1 Spotted Frog Sites/Populations in Areas Unaffected by the Proposed Action ............. 38 5.1.2 Spotted Frog Sites/Populations in Areas Affected by the Proposed Action ................. 39 5.1.2.1 Monitoring Spotted Frog Habitat within the Context of Water Management....... 40 5.1.2.2 Oregon Spotted Frog Sites above Wickiup Dam ................................................. 44 5.1.2.3 Oregon Spotted Frog Sites below Wickiup Dam ................................................ 55 5.2 Status of the Spotted Frog in the Little Deschutes River Sub-basin................................. 102 5.2.1 General Threats ....................................................................................................... 102 5.2.2 Spotted Frog Sites/Populations in Areas Unaffected by the Proposed Action ........... 105 5.2.2 Spotted Frog Sites/Populations in Areas Affected by the Proposed Action ............... 108 5.2.2.1 Ongoing Water Management and Hydrological Influences on Spotted FrogCritical Habitat ......................................................................................................................... 109 5.2.3 Influence of Water Management on Little Deschutes River Spotted Frog Habitat .... 119 5.3 Conservation Role of the Action Area for Spotted Frogs ................................................ 121 5.4 Status of Oregon Spotted Frog Critical Habitat .............................................................. 121 5.4.1 Critical Habitat Unit 8: Upper Deschutes River ....................................................... 123 5.4.2 Critical Habitat Unit 9: Little Deschutes River......................................................... 128 5.5 Conservation Role of the Action Area for Spotted Frog Critical Habitat ......................... 129 5.6 Climate Change ............................................................................................................. 130 6.0 EFFECTS OF THE ACTION: OREGON SPOTTED FROG AND OREGON SPOTTED FROG CRITICAL HABITAT ................................................................................................. 132 6.1 The OSF Proposal .......................................................................................................... 132 6.1.1 Methods used to Analyze Effects ............................................................................. 133 6.1.1.1 RiverWare-modeled Hydrology ....................................................................... 134 6.1.2 Effects in the Upper Deschutes River Sub-basin ...................................................... 135 6.1.2.1 Effects Above Wickiup Dam ............................................................................ 135 6.1.2.2 Effects Below Wickiup Dam ............................................................................ 141 6.1.3 Effects in the Little Deschutes River Sub-basin ....................................................... 160 6.1.3.1 RiverWare-modeled Flow Comparison of the OSF Proposal and Current Condition at the Crescent Lake Dam (CREO) Gauge ................................................... 164 6.1.3.2 RiverWare-modeled Flow Comparison of the OSF Proposal and Current Conditions in the Little Deschutes River at the La Pine, OR (LAPO) Gauge ................ 166 6.1.4 Acres of Spotted Frog Habitat Affected in the Upper Deschutes River and Little Deschutes River Sub-basins ............................................................................................. 168 6.1.4.1 Acres of Oregon Spotted Frog Habitat Affected in the Upper Deschutes River Sub-basin..................................................................................................................... 170 6.1.4.2 Acres of Oregon Spotted Frog Habitat affected by the Proposed Action in the Little Deschutes River Sub-basin ................................................................................. 176 6.2.1 Crane Prairie Reservoir ........................................................................................... 179 6.2.2 Deschutes River from Crane Prairie Dam to Wickiup Reservoir .............................. 180 6.2.3 Wickiup Reservoir................................................................................................... 180 6.2.4 Deschutes River from Wickiup Dam to the Little Deschutes River .......................... 181 6.2.5 Deschutes River from the Little Deschutes River to Colorado Street Bridge ............ 182 6.3 Effects to Oregon Spotted Frog Critical Habitat PCEs .................................................... 182 6.3.1 Effects of the OSF Proposal on Critical Habitat PCEs ............................................. 183 6.3.1.1 Effects of the OSF Proposal on Spotted Frog Critical Habitat Subunit 8A ........ 183 6.3.1.2 Effects of the OSF Proposal on Spotted Frog Critical Habitat Subunit 8B ........ 185 6.3.1.3 Effects of the OSF Proposal on the Recovery Support Function of Spotted Frog Critical Habitat Unit 9 ................................................................................................. 188 6.3.2 Effects of the ROM and SEED Programs on Critical Habitat PCEs ......................... 189 6.3.2.1 Effects of the ROM and SEED Programs on Spotted Frog Critical Habitat Subunit 8A ..............................................................................................................................