FINAL REPORT Arizona Game and Fish Department Heritage Grant “Inventory of the Meadow Jumping Mouse in Arizona” I09004 Zapus hudsonius luteus captured by J.K. Frey along the San Francisco River, Apache Co., AZ, 27 July 2008. Jennifer K. Frey, PhD Department of Fish, Wildlife and Conservation Ecology P.O. Box 30003, Campus Box 4901 New Mexico State University Las Cruces, New Mexico 88003-8003 575-640-9782 [email protected] 5 July 2011 Frey—Status of the Meadow Jumping Mouse in Arizona 2 DISCLAIMER The findings, opinions, and recommendations in this report are those of the investigators who have received partial or full funding from the Arizona Game and Fish Department Heritage Fund. The findings, opinions, and recommendations do not necessarily reflect those of the Arizona Game and Fish Commission or the Department, or necessarily represent official Department policy or management practice. For further information, please contact the Arizona Game and Fish Department. Frey—Status of the Meadow Jumping Mouse in Arizona 3 TABLE OF CONTENTS Title page 1 Disclaimer 2 Executive Summary 5 Introduction and Background 6 Methods 8 Historical records 8 Survey site selection 8 Jumping mouse sampling 9 Habitat data collection 10 Statistical analyses 11 Results and Discussion Historical records of Z. h. luteus White Mountains 15 Upper Verde River watershed 16 Distribution and abundance of Z. h. luteus 23 Habitat Stream reach cover 30 Microhabitat 33 Comparisons with other populations 37 Vertical cover height 38 Alders and willows 38 Livestock 41 Small mammal communities Diversity 45 Communities 47 Species patterns Dusky shrew 49 Water shrew 49 Thirteen-lined ground squirrel 60 Chipmunks 60 American beaver 61 Mexican woodrat 61 North American deermouse 62 Western harvest mouse 62 Montane vole 62 Long-tailed vole 65 Mogollon vole 66 Frey—Status of the Meadow Jumping Mouse in Arizona 4 Synthesis: Process of Population Extinction in Z. h. luteus 68 Summary of Major Findings 72 Management Recommendations 75 Acknowledgements 79 References 80 Appendix 1. Site Descriptions 86 Little Colorado River 87 San Francisco River 97 Blue River 101 Black River 104 Confidential Appendices Contents 113 (appendices are in separate file) Note added at submission of final report: Potential impacts of the 114 Wallow Fire on Zapus hudsonius luteus Frey—Status of the Meadow Jumping Mouse in Arizona 5 EXECUTIVE SUMMARY The New Mexico meadow jumping mouse (Zapus hudsonius luteus) was recently listed as a high priority candidate for protection on the federal Endangered Species Act. In Arizona, this riparian obligate is known to occur in the White Mountains and it is considered a threatened species and a species of greatest conservation need (Tier 1b). The purpose of this study was to evaluate the status of the species in Arizona. A review of records revealed that its historical distribution was broader than previously recognized, and included records in the Verde River watershed. Field surveys occurred during 2008-2009 at 35 survey sites in the White Mountains (14 historical, 21 new) including an effort of > 10,700 trap-nights. This represents the most comprehensive study of montane Z. h. luteus ever conducted. A total of 39 captures of Z. h. luteus occurred at 12 of 33 (36%) survey sites trapped. It was captured at only 6 of 12 (50%) historical locations sampled—all in the watershed of the Black River. It was not found at 3 of 9 (33%) historical sites where the species was known to occur as recently as the 1980-1990s. However, the overall persistence rate in the White Mountains (54%) was higher than for other populations in its range. Populations of Z. h. luteus were discovered at 6 new sites. These included the first records for Nutrioso Creek and Corduroy Creek. In addition, new records confirmed the persistence of the species in the East Fork Little Colorado River, San Francisco River, and Blue River watersheds. Habitat used by Z. h. luteus in the White Mountains was similar to that used by the species in other montane populations. It utilized tall, dense herbaceous vegetation composed primarily of forbs and sedges on saturate soil in close proximity to flowing water. However, not previously reported was the finding of a close association with alder at both a landscape and microhabitat scale. This association may be due to the additional cover provided by alder canopies. There was a significant positive relationship between alder cover with time since an area was excluded from livestock grazing. Habitat data collected at two historical locations on the West Fork of the Little Colorado River where there was heavy human recreational use (e.g., angling) indicated that habitat conditions were degraded and would not support Z. h. luteus. A total of 17 water shrews (Sorex palustris; considered endangered at the state level and a tier 1b species of greatest conservation need) were captured at 6 sites, making this the most successful study of that species. Records included two historical and one new location around the base of Mount Baldy, which had been considered its last refugium. Persistence of water shrews also was documented at West Fork Fish Creek and KP Creek, both of which had been considered extirpated. A new population was found on Rudd Creek, which represents the first record for the Nutrioso Creek watershed. Water shrews were captured on small streams on saturated soil with high vertical cover of herbaceous plants, primarily consisting of sedges. Livestock grazing has been regarded as the greatest threat to Z. h. luteus, and all current populations of Z. h. luteus in Arizona are in areas where livestock have been excluded. Other threats include recreation, loss of beaver, alterations to hydrology, drought, fire, and climate change. Z. h. luteus is particularly susceptible to threats due to factors such as a very low reproductive rate, limited dispersal ability, and use of linear habitats that are highly sensitive to disturbance. Consequently, a spiral of population extinctions can occur through a repeating sequential process whereby habitat alteration eliminates the species from a stream reach, which reduces the size of remaining reaches, and isolates them so that they cannot be recolonized. Unless populations are large enough and interconnected, continued population losses will occur. Management recommendations are made to recover the species. Frey—Status of the Meadow Jumping Mouse in Arizona 6 INTRODUCTION AND BACKGROUND The New Mexico meadow jumping mouse (Zapus hudsonius luteus) is a morphologically and genetically distinctive mammal that occurs in the American Southwest (Miller 1911; Hafner et al. 1981; King et al. 2006). Originally, this unique animal was recognized as a distinct species (Z. luteus), but later was considered a subspecies of the western jumping mouse (Z. princeps), and then a subspecies of the meadow jumping mouse (Z. hudsonius; Hafner et al. 1981). Recent molecular analyses have supported the close relationship to Z. hudsonius, but also indicated that luteus is a well-diverged, monophyletic group that may warrant species status (King et al. 2006; Malaney et al, in prep.). Z. h. luteus has a relict distribution composed of several known isolated populations: the White Mountains in eastern Arizona; the Sacramento, Jemez, and southern San Juan Mountains in New Mexico; the Sangre de Cristo mountains in southern Colorado and northern New Mexico; the Rio Grande Valley in New Mexico; and tributaries to the San Juan River in Colorado (Hoffmeister 1986; Morrison 1992; Frey 2005, 2006a,b, 2008, 2011). Z. h. luteus is a habitat specialist that occupies herbaceous emergent riparian habitats (Frey 2006b, Frey and Malaney 2009, Frey and Wright 2011). It is associated with saturated soils along perennial flowing water that supports tall, dense herbaceous vegetation, especially sedges (Frey 2006b, Frey and Malaney 2009, Frey and Wright 2011). Frey and Malaney (2009) and Frey and Wright (2011) reported extensive recent extirpations of populations in New Mexico over the past 2 decades. In montane regions, the primary identified threat to this taxon is livestock grazing, which can dramatically alter the structure and composition of herbaceous riparian vegetation (Morrison 1990, Frey and Malaney 2009). Other threats include drought and climate change, urbanization, water development, recreation, forest fire, flooding, loss of beaver, conversion of riparian habitat to agricultural crops, and management of irrigation delivery systems on large river floodplains (Morrison 1990, 1992; Hafner and Yensen 1998; NMDGF 1998; Frey 2005, 2006b, Frey and Wright 2011, AGFD 1996). In Arizona, it is currently considered a threatened species (AGFD 1996) and it is listed in the Arizona State Wildlife Action Plan (=Comprehensive Wildlife Conservation Strategy) as a species of greatest conservation need (Tier 1b) and a responsibility species (AGFD 2006). In addition, it has a Natural Heritage conservation status of globally rare and critically imperiled (S1) in Arizona and it is listed as sensitive by the US Forest Service Southwest Region. In New Mexico it was recently uplisted from threatened to endangered. In December 2007 it was listed as a high priority (listing priority 3) candidate for protection under the federal Endangered Species Act. In 2009 a spotlight species action plan for Z. h. luteus was approved with the goal to improve the status of the species within five years. In Arizona, information on the biology of Z. h. luteus is fragmentary and there is sparse information on its current status and ecological requirements. Hall and Davis (1934) reported the first records of Z. h. luteus in Arizona, which included 3 locations. Over the next 50 years, subsequent taxonomic revisions and regional faunal studies reported ca 9 additional locations (Krutzsch 1954, Cockrum 1960, Hafner et al. 1981, Hoffmeister 1986). Beginning in the 1980s several field studies occurred that attempted to provide information on distribution and status of Z. h. luteus in the White Mountains (e.g., Mills 1981, Dodd 1987, Morrison 1991, Koloszar and Ingraldi 1997).