MIGRATION PATTERNS OF ADULT FEMALE MULE DEER IN RESPONSE TO NATURAL-GAS DEVELOPMENT

Patrick Lendrum, ISU; Chuck Anderson, CPW; Terry Bowyer & John Kie, ISU; Jon Jenks, SDSU

Mule Deer Migration

Temperate regions

►Low-elevation winter ranges

►High-elevation summer ranges

►Spring

Winter to summer range

►Autumn

Summer to winter range

►Traditional routes Used for many

generations

Seasonally and yearly

►Travel great distances Average 35-55 km

~ 60 km

Objectives

►Map spring migration routes from

2008 to 2010

►Determine timing and synchrony

Departure and arrival

►Resource selection Environmental and landscape alterations

n =205 adult female mule deer

0

0.5

1

1.5

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3

North Ridge North Magnolia Ryan Gulch South Magnolia

Nu

mb

er

pa

ds/h

om

e r

an

ge

Timing of migration…

PK

► Snow depth

► Spring green-up

varied among years

highly synchronous across study areas within

years

► Deer in better condition departed winter

range earlier.

Factors Influencing Migration Timing

120 125 130 135 140 145 150

Snow

Depth

(cm

)

0

20

40

60

80

100

120

140

2008

2009

2010

Resource-selection Functions

►Use vs. availability GPS locations vs. random locations

►Step length

Distance between 2 consecutive locations

► Turning angle

Angle between steps

► Conditional logistic regression

Resource Selection

Environmental

►Elevation

►Slope

►Aspect

►Terrain ruggedness

►Vegetation type

Landscape Alterations

►Roads

►Well pads

►Pipelines

Od

ds

rati

o

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1.00

2.00

3.00

4.00

5.00

North East West

Od

ds

rati

o

0.00

1.00

2.00

3.00

4.00

5.00

North Ridge (Low)

North Magnolia (Medium-low)

Ryan Gulch (Medium-high)

South Magnolia (High)

A)

B)

Herbaceous PJ Forest Barren Riparian

Odd

s ra

tio

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Odd

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North Ridge (Low)

North Magnolia (Medium-low)

Ryan Gulch (Medium-high)

South Magnolia (High)

A)

B)

Day

Night

Migration Summary ►Mule deer moved more quickly through the most

developed areas

► Selected habitats with increased cover.

►Avoided roads except in the most developed area

High road densities may preclude avoidance

► Selected areas close to well pads

Predator avoidance? elk competition? foraging opportunities?

Conclusion

Deer may avoid disturbance where feasible or increase their rate of travel through highly developed landscapes where the energetic cost of avoidance may be too high

Acknowledgements

Advisors

► Dr. Terry Bowyer - ISU

► Dr. Chuck Anderson - CPW

► Dr. John Kie - ISU

► Dr. Jonathan Jenks - SDSU

Funding

Colorado Parks and Wildlife, Federal Aid in Wildlife Restoration, Colorado Mule Deer Association, Colorado Mule Deer Foundation, Colorado Oil and Gas Conservation Commission, EnCana Corp., Williams Production LMT CO., Exxon Mobil Production Co., Shell Petroleum, Marathon Oil Corp.

Additional Support

Colorado Parks and Wildlife, Quicksilver Air Inc., Coulter Aviation, White River Bureau of Land Management, U.S. Forest Service

Questions?

SD Min. Max. SD Min. Max.

Elevation (m)

North Ridge 2,158.94 184.20 1,764.38 2,795.23 2,261.61 266.30 1,721.67 3,344.86

North Magnolia 2,297.23 148.20 1,912.75 2,838.41 2,300.51 253.50 1,757.44 3,428.61

Ryan Gulch 2,269.04 172.40 1,871.76 2,799.31 2,255.67 207.70 1,511.37 3,075.65

South Magnolia 2,314.25 169.90 1,915.48 2,745.73 2,269.74 214.00 1,520.88 2,812.14

Slope (%)

North Ridge 11.21 6.80 0.09 39.38 12.66 8.10 0.00 50.50

North Magnolia 11.86 7.30 0.13 40.22 13.18 8.30 0.00 62.58

Ryan Gulch 10.91 6.90 0.03 36.63 14.04 8.90 0.00 63.26

South Magnolia 11.96 6.80 0.01 34.67 15.45 9.50 0.00 69.88

Terrain ruggedness

North Ridge 0.07 0.13 0.00 0.88 0.07 0.13 0.00 0.97

North Magnolia 0.08 0.14 0.00 0.96 0.08 0.14 0.00 0.96

Ryan Gulch 0.09 0.10 0.00 0.87 0.10 0.15 0.00 0.93

South Magnolia 0.09 0.10 0.00 0.84 0.10 0.15 0.00 0.97

Used locations Random locationsVariables and

Study area x x

SD Min. Max. SD Min. Max.

Distance to well pads (m)

North Ridge 17,329.86 13,864.40 604.31 89,412.57 23,413.54 19,730.00 0.00 95,251.58

North Magnolia 9,122.54 10,165.20 195.85 73,566.37 16,294.64 15,908.00 0.00 80,021.54

Ryan Gulch 3,104.30 3,581.60 45.32 33,431.44 3,712.87 4,899.90 0.00 39,264.85

South Magnolia 3,362.08 2,866.80 64.71 22,523.16 5,379.02 5,806.00 0.00 30,231.00

Distance to roads (m)

North Ridge 1,592.32 1,136.00 2.11 8,116.62 1,718.93 1,449.00 0.00 7,966.56

North Magnolia 1,181.47 1,121.60 0.36 5,606.49 1,298.99 1,217.30 0.00 7,150.39

Ryan Gulch 752.15 840.10 1.42 6,801.27 609.19 866.00 0.00 6,730.35

South Magnolia 440.82 639.60 0.67 6,467.18 829.16 1,145.40 0.00 6,667.89

Variables and

Study area

Used locations Random locations

x x