A Biological Inventory and Conservation Recommendations for the Great Sand Dunes and San Luis Lakes, Colorado Colorado Natural Heritage Program Colorado State University College of Natural Resources 254 General Services Building Ft. Collins, Colorado 80523 March 1999 i A Biological Inventory and Conservation Recommendations for the Great Sand Dunes and San Luis Lakes, Colorado MARCH 1999 PREPARED BY: PHYLLIS M. PINEDA RENÉE J. RONDEAU AND ANNE OCHS PREPARED FOR: THE NATURE CONSERVANCY, SAN LUIS VALLEY PROGRAM† SAGUACHE, COLORADO †P.O. Box 674, Saguache, Colorado 81149 ii Biological Inventory of the Great Sand Dunes and San Luis Lakes. Pineda et al. 1999 __________________________________________________________________________________ TABLE OF CONTENTS USERS GUIDE/BACKGROUND INFORMATION .............................................................................. IV GLOSSARY................................................................................................................................................ IV ACKNOWLEDGMENTS............................................................................................................................V EXECUTIVE SUMMARY .......................................................................................................................... 1 INTRODUCTION........................................................................................................................................ 3 STUDY AREA .............................................................................................................................................. 5 Climate.................................................................................................................................................. 5 Geology and soils.................................................................................................................................. 5 The Great Sand Dunes eolian depositional system............................................................................... 5 Cultural history..................................................................................................................................... 9 MAJOR THREATS AND STRESSES TO THE BIODIVERSITY OF THE GREAT SAND DUNES AND THE SAN LUIS LAKES .................................................................................................................. 11 RECOMMENDATIONS ........................................................................................................................... 14 BACKGROUND......................................................................................................................................... 16 COLORADO’S NATURAL HERITAGE PROGRAM ......................................................................................... 16 WHAT IS BIOLOGICAL DIVERSITY?........................................................................................................... 17 PROTECTION URGENCY RANKS ................................................................................................................ 21 MANAGEMENT URGENCY RANKS............................................................................................................. 21 ELEMENT OCCURRENCE RANKS ............................................................................................................... 22 POTENTIAL CONSERVATION AREAS ......................................................................................................... 23 POTENTIAL CONSERVATION AREA BOUNDARIES ..................................................................................... 23 OFF-SITE CONSIDERATIONS ..................................................................................................................... 24 RANKING OF CONSERVATION AREAS ....................................................................................................... 24 LEGAL DESIGNATIONS ............................................................................................................................. 25 METHODS.................................................................................................................................................. 26 RESULTS.................................................................................................................................................... 28 TARGETED INVENTORY AREAS ................................................................................................................ 28 ELEMENTS OF BIODIVERSITY SIGNIFICANCE ............................................................................................ 38 POTENTIAL CONSERVATION AREAS ......................................................................................................... 40 POTENTIAL CONSERVATION AREA PROFILE .............................................................................. 41 GREAT SAND DUNES ................................................................................................................................ 43 SAN LUIS LAKES ...................................................................................................................................... 51 REFERENCES AND LITERATURE CITED......................................................................................... 59 APPENDIX A. CHARACTERIZATION ABSTRACTS....................................................................... 61 INSECTS .................................................................................................................................................... 62 Amblyderus triplehorni ....................................................................................................................... 62 Amblyderus werneri............................................................................................................................ 64 Cicindela theatina............................................................................................................................... 65 Daihinibaenetes giganteus.................................................................................................................. 67 ii Biological Inventory of the Great Sand Dunes and San Luis Lakes. Pineda et al. 1999 __________________________________________________________________________________ Eleodes hirtipennis.............................................................................................................................. 69 Hypocaccus undesc. sp. ...................................................................................................................... 70 Polites sabuleti ministigma ................................................................................................................. 71 Proctacanthus n.sp.............................................................................................................................. 72 Schinia avemensis ............................................................................................................................... 73 MAMMALS................................................................................................................................................ 75 Cynomys gunnisoni gunnisoni ............................................................................................................ 75 Dipodomys ordii montanus ................................................................................................................. 76 Perognathus flavescens relictus.......................................................................................................... 77 Perognathus flavus sanluisi ................................................................................................................ 78 Spemophilus tridecemlineatus blanca................................................................................................. 79 Thomomys talpoides agrestis.............................................................................................................. 80 BIRDS ....................................................................................................................................................... 81 Amphispiza belli.................................................................................................................................. 81 Buteo regalis....................................................................................................................................... 83 FISH.......................................................................................................................................................... 84 Oncorhynchus clarki virginalis........................................................................................................... 84 LITERATURE CITED FOR APPENDIX A....................................................................................................... 85 TABLE OF FIGURES FIGURE 1. GEOGRAPHICAL LOCATION OF THE GREAT SAND DUNES AND SAN LUIS LAKES............................ 4 FIGURE 2. PROVINCES OF THE GREAT SAND DUNES DEPOSITIONAL SYSTEM. ............................................. 10 FIGURE 3. TARGETED INVENTORY AREAS FOR THE MEDANO-ZAPATA RANCH AND THE SAN LUIS LAKES AREA. .................................................................................................................................................. 29 FIGURE 4. GREAT SAND DUNES POTENTIAL CONSERVATION AREA LAND OWNERSHIP MAP........................