Mammal Surveys in Great Basin National Park:Assessment of Historical Faunal Change

Eric Rickart & Shannen Robson

Utah Museum of Natural HistoryUniversity of Utah

METHODS

Historical data sources

Museum of Vertebrate Zoology (MVZ)1929-1939 field surveys

Other records – 1940-1990 Publications MaNIS museum network

UMNH-FMNH survey – 2000

NPS I&M (UMNH) – 2002-2003

Recent data sources

GRBA sight reports – 1994-2004

GENERAL SURVEY RESULTS

Historical records (pre-1990)

Park: 390 records 31 species Park region: 893 records 48 species

Recent surveys (2000-2003)

4379 trap nights 642 records 26 species

GRBA sight reports

366 reports 22 species

(non-volant mammals)

Species Totals Park Greater region

Non-volants 42 54 Total (incl. bats) 49 67

Shrews (small mammal exemplars)

Merriam’s shrew (Sorex merriami)Sagebrush

Inyo shrew (Sorex tenellus)High elevations (rocky substrate)

Vagrant shrew (Sorex vagrans)

Abundant generalist

Water shrew (Sorex palustris)

Uncommon riparian specialist

Uncommon habitat specialists

1930 2003

Historical change

Piñon-Juniper expansion

Invasive cheatgrass

Resurvey protocol

Relocate historical collecting sites that were densely sampled

Determine historical sampling effort

Assess habitat changes (notes and photographs)

Do comparable modern sampling

Interpret local faunal changes

Local site assessments:

Broader scale (landscape) assessments:

Shifts in elevation ranges of species

Specimen counts as a proxy for effort

Survey localities

Historical &RecentSurvey

comparison

= historical record = recent record

Resurvey comparisons -- Four elevation “bins”

Low: 5300-6700 ft 67 10 65 12 (ca. 1600-2050 m)

Mid: 7000-8000 ft 125 14 56 7 (ca. 2150-2450 m)

High: 8100-10500 ft 79 7 80 8 (ca. 2450-3200 m)

Alpine: 10700-11200 ft 30 7 28 5 (ca. 3250-3400 m)

Historical ModernElevation (1929-1939) (2000-2003) records species records species

Low elevation

Low elevation

Mid elevation

Mid elevation

High elevation

High elevation

Alpine

Alpine

Least chipmunk (Tamias minimus) Great Basin pocket mouse (Perognathus parvus)

Species responding to loss/shift of sagebrush habitat

Uinta chipmunk (Tamias umbrinus)

Piñon mouse (Peromyscus truei)

Species increasing with spread of piñon-juniper

Species responding to cheatgrass invasion

Ord’s kangaroo rat (Dipodomys ordii)

Declining

Expanding

Harvest mouse (Reithrodontomys megalotis)

Long-tailed vole (Microtus longicaudus)

Desert woodrat (Neotoma lepida)Bushy-tailed woodrat

(Neotoma cinerea)

Declining woodrats

Yellow-bellied marmot(Marmota flaviventris)

Porcupine(Erethizon dorsatum)

Uncommon species

Cougar(Puma concolor)

Beaver(Castor canadensis)

Keystone species

Acknowledgements

Field assistantsDanny BaleteAlex BaughLarry HeaneyRob McIntyreJoe Walsh

GRBA - NPSGretchen BakerBryan HamiltonKris HeisterJoe SirotnakTod Williams

FundingUtah Museum of Natural HistoryField MuseumNPS Mojave network I&M program