ASH MEADOWS NATIONAL WILDLIFE REFUGE The Contributions of Insect Pollinators to the Reproductive Fitness of 12 Rare Plants on Ash Meadows National Wildlife Refuge Final Report February 2012 David A. Tanner, Nicole F. Boehme, Catherine M. Clark, and James P. Pitts Department of Biology, Utah State University, Logan, Utah Submitted to: Ash Meadows National Wildlife Refuge c/o Desert National Wildlife Refuge Complex 4701 N Torrey Pines Las Vegas, NV 89130 Submitted by: BIO-WEST, Inc. 1063 West 1400 North Logan, UT 84321 TABLE OF CONTENTS 1.0 GENERAL INTRODUCTION ............................................................................................ 1 2.0 RARE PLANTS OF ASH MEADOWS NATIONAL WILDLIFE REFUGE USED IN THE STUDY .................................................................................................................. 2 2.1 Arctomecon merriamii .................................................................................................. 2 2.1.1 General Information ................................................................................................ 2 2.1.2 Importance to Pollinators ........................................................................................ 3 2.2 Astragalus phoenix........................................................................................................ 3 2.2.1 General Information ................................................................................................ 3 2.2.2 Importance to Pollinators ........................................................................................ 4 2.3 Calochortus striatus ...................................................................................................... 4 2.3.1 General Information ................................................................................................ 4 2.3.2 Importance to Pollinators ........................................................................................ 4 2.4 Centaurium namophilum .............................................................................................. 5 2.4.1 General Information ................................................................................................ 5 2.4.2 Importance to Pollinators ........................................................................................ 5 2.5 Cordylanthus tecopensis ............................................................................................... 5 2.5.1 General Information ................................................................................................ 5 2.5.2 Importance to Pollinators ........................................................................................ 6 2.6 Enceliopsis nudicaulis var. corrugata .......................................................................... 6 2.6.1 General Information ................................................................................................ 6 2.6.2 Importance to Pollinators ........................................................................................ 6 2.7 Grindelia fraxino-pratensis .......................................................................................... 7 2.7.1 General Information ................................................................................................ 7 2.7.2 Importance to Pollinators ........................................................................................ 7 2.8 Ivesia kingii var. eremica .............................................................................................. 7 2.8.1 General Information ................................................................................................ 7 2.8.2 Importance to Pollinators ........................................................................................ 8 2.9 Mentzelia leucophylla ................................................................................................... 8 2.9.1 General Information ................................................................................................ 8 2.9.2 Importance to Pollinators ........................................................................................ 8 2.10 Nitrophila mohavensis .................................................................................................. 9 2.10.1 General Information ................................................................................................ 9 2.10.2 Importance to Pollinators ........................................................................................ 9 2.11 Sisyrinchium spp. .......................................................................................................... 9 2.11.1 General Information ................................................................................................ 9 2.11.2 Importance to Pollinators ........................................................................................ 9 2.12 Spiranthes infernalis ................................................................................................... 10 2.12.1 General Information .............................................................................................. 10 2.12.2 Importance to Pollinators ...................................................................................... 10 U.S. Fish and Wildlife Service Contributions of Insect Pollinators Ash Meadows NWR i to the Reproductive Fitness of 12 Rare Plants 3.0 TASK 4: IDENTIFY RARE PLANT POLLINATORS AT ASH MEADOWS NATIONAL WILDLIFE REFUGE .................................................................................. 10 3.1 Methods....................................................................................................................... 10 3.1.1 Study Sites ............................................................................................................ 10 3.1.2 Pollinator Observations and Collections ............................................................... 11 3.1.3 Pollen Reference Library ...................................................................................... 11 3.1.4 Pollen Quantification ............................................................................................ 12 3.1.5 Pollinator Classification ........................................................................................ 12 3.2 Results ......................................................................................................................... 13 3.2.1 Arctomecon merriamii .......................................................................................... 13 3.2.2 Astragalus phoenix................................................................................................ 14 3.2.3 Calochortus striatus .............................................................................................. 15 3.2.4 Centaurium namophilum ...................................................................................... 17 3.2.5 Cordylanthus tecopensis ....................................................................................... 19 3.2.6 Enceliopsis nudicaulis var. corrugata .................................................................. 20 3.2.7 Grindelia fraxino-pratensis .................................................................................. 22 3.2.8 Ivesia kingii var. eremica ...................................................................................... 24 3.2.9 Mentzelia leucophylla ........................................................................................... 25 3.2.10 Nitrophila mohavensis .......................................................................................... 27 3.2.11 Sisyrinchium spp. .................................................................................................. 28 3.2.12 Spiranthes infernalis ............................................................................................. 28 3.3 Discussion ................................................................................................................... 29 3.3.1 Is There a Guild of Pollinators Uniquely Important to the Rare Plants of the Refuge? ....................................................................................................... 32 4.0 TASK 5: IDENTIFY THE POLLINATORS OF OTHER CONCURRENTLY BLOOMING FLOWERS .................................................................................................. 35 4.1 Introduction ................................................................................................................. 35 4.2 Methods....................................................................................................................... 35 4.2.1 Plant Identification ................................................................................................ 35 4.2.2 Insect Collection ................................................................................................... 36 4.2.3 Insect Preservation and Identification ................................................................... 36 4.3 Results ......................................................................................................................... 36 4.3.1 Asclepias ............................................................................................................... 36 4.3.2 Creosote ................................................................................................................ 37 4.3.3 Enceliopsis ...........................................................................................................