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Report May Be Cited As: Harkness, Mary, Jennifer S CONSERVING THE BIOLOGICAL DIVERSITY OF THE DAKOTA MIXED -GRASS PRAIRIE Mary Harkness Jennifer S. Hall Paula Gagnon Phil Gerla Minneapolis, MN Ann Arbor, MI Portland, OR Univ. of North Dakota [email protected] [email protected] [email protected] 81 Cornell St., Stop 8358 Grand Forks ND 58202 [email protected] Meredith Cornett Brian Schreurs Sarah Eichhorst 394 Lake Ave. S. Minneapolis, MN 1101 West River Pkwy Duluth, MN 55805 [email protected] Suite 200 [email protected] Minneapolis MN 55414 [email protected] May 1, 2010 This report may be cited as: Harkness, Mary, Jennifer S. Hall, Paula Gagnon, Phil Gerla, Meredith W. Cornett, Brian Schreurs, and Sarah Eichhorst. 2010. Conserving the biological diversity of the Dakota Mixed- Grass Prairie. The Nature Conservancy, Minneapolis MN. Funding for the completion of this report was generously provided by The Cox Family Fund for Science and Research. This report and its appendices are available for download: http://conserveonline.org/workspaces/dmgp TABLE OF CONTENTS 1 ACKNOWLEDGMENTS ................................................................................................................................................... 4 2 INTRODUCTION ............................................................................................................................................................. 5 3 ECOREGION OVERVIEW ................................................................................................................................................. 5 3.1 GEOGRAPHIC SETTING ............................................................................................................................................................5 3.2 TERRESTRIAL CONTEXT ...........................................................................................................................................................8 3.3 AQUATIC CONTEXT ..............................................................................................................................................................10 3.4 LAND USE CONTEXT .............................................................................................................................................................11 4 ECOREGIONAL ASSESSMENT PROCESS OVERVIEW ...................................................................................................... 13 4.1 SETTING PRIORITIES .............................................................................................................................................................13 4.2 ECOLOGICAL STRATIFICATION UNITS ........................................................................................................................................15 4.3 TERRESTRIAL ECOREGIONAL SECTIONS AND DESCRIPTIONS ...........................................................................................................15 4.3.1 Northeastern Glaciated Plains Section (332A) ......................................................................................................15 4.3.2 Western Glaciated Plains Section (332B) ..............................................................................................................15 4.3.3 North Central Great Plains Section (332D) ............................................................................................................15 4.4 FRESHWATER ECOLOGICAL DRAINAGE UNITS AND DESCRIPTIONS ..................................................................................................17 4.4.1 James River............................................................................................................................................................17 4.4.2 Middle Missouri River ............................................................................................................................................19 4.4.3 Devils Lake .............................................................................................................................................................19 4.4.4 Sand Hills ...............................................................................................................................................................20 4.4.5 Middle Souris River ................................................................................................................................................20 4.4.6 Red River Basin – West ..........................................................................................................................................21 5 DATA AND INFORMATION SOURCES ........................................................................................................................... 21 5.1 UNTILLED LANDSCAPES AND RAPID ECOLOGICAL ASSESSMENTS ....................................................................................................21 5.2 GRASSLAND BIRD CONSERVATION AREAS AND WATERFOWL BREEDING AREAS ................................................................................22 5.2.1 HAPET Grassland Bird Conservation Area (GBCA) Models ....................................................................................22 5.2.2 HAPET Waterfowl Breeding Area Models .............................................................................................................24 5.3 HERITAGE ELEMENT OCCURRENCE DATA ..................................................................................................................................26 5.4 2001 NATIONAL LAND COVER DATABASE (NLCD) ....................................................................................................................26 5.5 NATIONAL AGRICULTURE IMAGERY PROGRAM (NAIP) ...............................................................................................................26 5.6 SOIL SURVEY GEOGRAPHIC DATABASE (SSURGO).....................................................................................................................27 5.7 AQUATIC ECOLOGICAL SYSTEM CLASSIFICATION .........................................................................................................................27 5.8 FRESHWATER SPECIES AND ASSEMBLAGE DATA .........................................................................................................................27 5.9 EXPERT MEETINGS AND INPUT ...............................................................................................................................................28 5.9.1 Aquatic Expert Workshop ......................................................................................................................................28 5.9.2 Aquatic Expert Workshop ......................................................................................................................................29 6 STRENGTHS AND LIMITATIONS OF THE DMGP ASSESSMENT ....................................................................................... 29 7 CONSERVATION TARGETS AND TARGET OCCURRENCES .............................................................................................. 30 7.1 TERRESTRIAL ECOLOGICAL SYSTEMS ........................................................................................................................................30 7.2 TERRESTRIAL PLANT COMMUNITIES .........................................................................................................................................31 7.3 TERRESTRIAL NON -AVIAN SPECIES ..........................................................................................................................................32 7.4 AVIAN SPECIES ....................................................................................................................................................................34 7.5 FRESHWATER SPECIES AND ASSEMBLAGES ................................................................................................................................36 7.6 FRESHWATER ECOLOGICAL SYSTEMS ........................................................................................................................................36 8 CONSERVATION GOALS ............................................................................................................................................... 37 8.1 TERRESTRIAL ECOLOGICAL SYSTEMS ....................................................................................................................................... 38 8.2 TERRESTRIAL PLANT COMMUNITIES ........................................................................................................................................ 38 8.3 TERRESTRIAL NON -AVIAN SPECIES ......................................................................................................................................... 38 8.4 AVIAN SPECIES ................................................................................................................................................................... 39 8.5 FRESHWATER SPECIES , ASSEMBLAGES , AND AQUATIC ECOLOGICAL SYSTEMS .................................................................................. 39 9 VIABILITY/INTEGRITY .................................................................................................................................................. 39 9.1 TERRESTRIAL ECOLOGICAL SYSTEMS AND PLANT COMMUNITIES ..................................................................................................
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