Clarifying the Distribution and Ecology of Pocket Mice in Wyoming

Trapping protocol for difficult to detect small mammals

Kristina Harkins1*, Merav Ben-David1, Doug Keinath2 1Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071 2U. S. Fish and Wildlife Service, Cheyenne, WY 82009 © Laila Bahaa-el-din/Panthera Ecosystems and species’ ranges are changing rapidly

In Wyoming

» Species of Greatest

Conservation NeedWGFD 2010 » Bats: 11 species » Rabbits: 2 species » Rodents: 18 species » Shrews: 5 species Pocket Mice

» Family: Heteromyidae – 2 genera » Fur-lined exterior cheek pouches for storing and carrying food » Cheatgrass (Bromus tectorum) thought

to have negativeCeradini unpublished impact; Ostoja et al. 2013; Richardson et al. 2013 © Tegan May » Most studies done at small scale with small scale habitat variables Heisler et al. 2013

Silky Pocket Mouse Plains Pocket Mouse Olive-backed Pocket Mouse Great Basin Pocket Mouse Perognathus flavus Perognathus flavescens Perognathus fasciatus Perognathus parvus Pocket Mice are Rare

1. Difficult to detect because of standard trapping protocol: • Sherman Live Traps • Peanut Butter (and oats)

2. Wyoming habitat a-typical for pocket mice.

3. Poor competitors and therefore rare. Project Goals

Can we create a protocol that maximizes pocket mouse captures?

What habitat characteristics are selected by these species?

Are pocket mice excluded from desirable locations due to competition with deer mice (Peromyscus maniculatus)? What trapping method can maximize pocket mouse captures? Sampling Effort Typical Trapping Grid: 10 X 10, 10m Spacing Hanser et. al. 2011 Ostoja and Schupp 2009 Dizney et. al. 2008 Manor and Saltz 2008 Mullican et. al. 2005 Kuenzi et. al. 2005

“Average” Trap Area Effort 10 hectares, square 100 traps per grid Proposed Trap Area Effort 35.6 hectares, rectangular and long 160-180 traps per grid

Trap and Bait Protocol

4x20 Trapping Grid – 25 meter spacing

Trap Types: Bait Types: Set Up: Havahart Peanut Butter 2-3 traps per point Longworth Horse Feed Polyester bedding Sherman Bird Seed Rotate bait types

Longworth traps only on 1 trap line per grid

<2300m elevation <30% tree canopy cover Methods

Trapped 4 consecutive nights per site

Each individual uniquely marked PIT Tag or Ear Tag + Hair Clip

2016 52 sites 19 species 1782 unique individuals 72.7% captures were deer mice 4 pocket mouse species: 119 individuals Capture Success

2015 2016 Species Scientific Name Individuals Total Individual Total Deer Mouse Peromyscus maniculatus 2776 5399 1198 2550 Ord's Kangaroo Rat Dipodomys ordii 516 881 227 422 Western Harvest Mouse Reithrodontomys megalotis 159 290 45 99 Olive-backed Pocket Mouse Perognathus fasciatus 130 187 92 155 Least Chipmunk Tamias minimus 110 132 63 91 Sagebrush Vole Lemmiscus curtatus 170 188 23 24 Plains Harvest Mouse Reitrodontomys montanus 101 140 4 5 Prairie Vole Microtus ochrogaster 91 98 15 15 Thirteen-lined Ground Squirrel Ictidomys tridecemlineatus 43 57 42 47 Northern Grasshopper Mouse Onychomys leucogaster 28 35 30 46 Hispid Pocket Mouse Chaetodipus hispidus 5 6 17 29 Microtus Vole Species Microtus species 12 18 3 3 Bushy-tailed Woodrat Neotoma cinerea 9 11 5 6 Great Basin Pocket Mouse Perognathus parvus 9 12 1 1 Wyoming Ground Squirrel Urocitellus elegans 0 0 9 10 Long-tailed Vole Microtus longicaudus 7 7 1 2 Plains Pocket Mouse Perognathus flavescens 5 8 0 0 Montane Vole Microtus montanus 1 1 2 3 Cottontail Rabbit Species Sylvilagus species 2 2 1 1 Silky Pocket Mouse Perognathus flavus 0 0 1 2 Shrew Species Sorex Species 1 1 0 0 Long-tailed Weasel Mustela frenata 0 0 1 1 Grand Total 4179 7478 1782 3517 Species Richness by Site Significant 16 14 variation 12 10

8 within small 2015 6 2016 mammal OF NUMBER SITES 4 2

0 communities 0 1 2 3 4 5 6 7 8 9 NUMBER OF SPECIES TRAPPED AT A SITE What trapping method can maximize pocket mouse captures? Do granivorous rodents select seeds? Multi-state Model » Individual variation » Bait and trap switching

All Pocket Mouse Captures © Tegan May 200 180 160 140

120 100 80 Captures 60 40 20 0 Havahart Havahart Havahart Sherman Sherman Sherman Bird Seed Horse Feed Peanut Bird Seed Horse Feed Peanut Butter Butter Trap+Bait Preferences – Pocket Mice

Compositional analysis of habitat use.

HA_BS HA_HF LW_BS LW_HF LW_PB HA_PB SH_BS SH_PB SH_HF HA_BS ------HA_HF ------LW_BS ------LW_HF ------LW_PB ------HA_PB ------SH_BS ------SH_PB ------SH_HF ------

HA = Havahart, LW = Longworth, SH = Sherman BS = Bird Seed, HF = Horse Feed, PB = Peanut Butter

HA_BS HA_HF All Longworths HA_PB SH_BS SH_PB SH_HF +++ ++ + + + ------Additional Species

Deer Mice Kangaroo Rat All Voles

HA_PB +++ HA_BS +++ LW_PB ++ HA_BS +++ HA_PB +++ LW_BS + HA_HF +++ HA_HF +++ LW_HF + HA_HF + LW_PB + LW_PB + HA_BS + SH_PB + LW_BS + HA_PB + LW_HF -- SH_BS -- LW_BS -- SH_PB ------LW_HF -- -- SH_BS ------SH_BS ------SH_PB ------SH_HF ------SH_HF ------SH_HF ------Trap performance

0.8

0.7

0.6

0.5

Empty Traps 0.4 Captures Percent Bushy-tailed Woodrat 0.3

0.2

0.1

0 Havahart Sherman Longworth Overall

• Shift our trap protocol ideas • 67% all captures in Havaharts • Future studies • Target trapping

Advisors Technicians Dr. Merav Ben-David Tegan May (x3!) Dr. Doug Keinath Maddy Pfaff Committee Members Bre Dodge Dr. Jake Goheen Alicia Sullivan Dr. Shannon Albeke Briana All Lab Mates Bobby Riotto Dr. Carolyn Ekrich Volunteers Adi Barocas Michael Tweedie Bobby Riotto Taylor Berge Cody Trainer Megan Dai Sean Harkins WYNDD family And many, All our dogs many more! Questions?