FINAL Biological Assessment for the Casper Field Office Proposed Resource Management Plan May 2007 Final Biological Assessment for the Casper Field Office Proposed Resource Management Plan U.S. Department of the Interior Bureau of Land Management Casper Field Office, Wyoming May 2007 TABLE OF CONTENTS 1.0 INTRODUCTION........................................................................................................................................... 1-1 1.1 Proposed Plan ........................................................................................................................................ 1-3 1.1.1 Physical, Biological, and Heritage Resources ............................................................................ 1-3 1.1.2 Resource Uses and Support........................................................................................................ 1-3 1.1.3 Special Designations .................................................................................................................. 1-4 2.0 CONSULTATION AND BIOLOGICAL ASSESSMENT OBJECTIVES ................................................ 2-1 3.0 OVERVIEW OF THE PLANNING AREA.................................................................................................. 3-1 3.1 Natrona County ..................................................................................................................................... 3-1 3.2 Converse County ................................................................................................................................... 3-2 3.3 Platte County ......................................................................................................................................... 3-2 3.4 Goshen County ...................................................................................................................................... 3-3 4.0 CURRENT STATUS AND HABITAT USE OF SPECIAL STATUS SPECIES ...................................... 4-1 4.1 Bald Eagle ............................................................................................................................................. 4-2 4.1.1 Status .......................................................................................................................................... 4-2 4.1.2 Life History ................................................................................................................................ 4-2 4.1.3 Habitat Requirements ................................................................................................................. 4-2 4.1.4 Regional and Local Distribution................................................................................................. 4-3 4.1.5 Threats........................................................................................................................................ 4-3 4.2 Black-footed Ferret................................................................................................................................ 4-4 4.2.1 Status .......................................................................................................................................... 4-4 4.2.2 Life History ................................................................................................................................ 4-4 4.2.3 Habitat Requirements ................................................................................................................. 4-5 4.2.4 Regional and Local Distribution................................................................................................. 4-5 4.2.5 Threats........................................................................................................................................ 4-6 4.3 Blowout Penstemon............................................................................................................................... 4-6 4.3.1 Status .......................................................................................................................................... 4-6 4.3.2 Life History ................................................................................................................................ 4-6 4.3.3 Habitat Requirements ................................................................................................................. 4-7 4.3.4 Regional and Local Distribution................................................................................................. 4-7 4.3.5 Threats........................................................................................................................................ 4-7 4.4 Colorado Butterfly Plant and Designated Critical Habitat..................................................................... 4-8 4.4.1 Status .......................................................................................................................................... 4-8 4.4.2 Life History ................................................................................................................................ 4-8 4.4.3 Habitat Requirements ................................................................................................................. 4-8 4.4.4 Regional and Local Distribution................................................................................................. 4-9 4.4.5 Threats........................................................................................................................................ 4-9 4.4.6 Designated Critical Habitat .......................................................................................................4-10 4.5 Preble’s Meadow Jumping Mouse and Designated Critical Habitat ....................................................4-10 4.5.1 Status .........................................................................................................................................4-10 4.5.2 Life History ...............................................................................................................................4-10 4.5.3 Habitat Requirements ................................................................................................................4-10 4.5.4 Regional and Local Distribution................................................................................................4-11 4.5.5 Threats.......................................................................................................................................4-11 4.5.6 Designated Critical Habitat .......................................................................................................4-11 4.6 Ute Ladies’-Tresses ..............................................................................................................................4-12 4.6.1 Status .........................................................................................................................................4-12 4.6.2 Life History ...............................................................................................................................4-12 4.6.3 Habitat Requirements ................................................................................................................4-12 4.6.4 Regional and Local Distribution................................................................................................4-13 4.6.5 Threats.......................................................................................................................................4-13 Casper Final Biological Assessment i 5.0 SPECIES WITH HABITAT DOWNSTREAM (PLATTE RIVER) THAT MAY BE AFFECTED BY WATER DEPLETION RESULTING FROM BLM-AUTHORIZED ACTIONS WITHIN THE CASPER PLANNING AREA........................................................................... 5-1 5.1 Introduction ........................................................................................................................................... 5-1 5.2 Eskimo Curlew ...................................................................................................................................... 5-1 5.2.1 Status .......................................................................................................................................... 5-1 5.2.2 Life History ................................................................................................................................ 5-1 5.2.3 Habitat Requirements ................................................................................................................. 5-2 5.2.4 Regional and Local Distribution................................................................................................. 5-2 5.2.5 Threats........................................................................................................................................ 5-2 5.3 Interior Least Tern................................................................................................................................. 5-2 5.3.1 Status .......................................................................................................................................... 5-2 5.3.2 Life History ................................................................................................................................ 5-2 5.3.3 Habitat Requirements ................................................................................................................. 5-2 5.3.4