Addressing Deer Vehicle Accidents at the Community Scale

Elizabeth I. Rogers, Ph.D.

Dean B. Premo, Ph.D.

White Water Associates, Inc.

Amasa, MI

Creating a Town Deer-Vehicle Accident Management Plan

Project Goals

• Use the existing GIS project to understand deer-vehicle accident patterns

• Create a deer-vehicle accident management plan

• Assess data collection and monitoring needs for the future

The starting point: Town GIS Project

• Town of Amherst, (roads, boundary)

• Land Use Layer (urban, suburban, and rural land uses)

• Deer-Vehicle Accident Management Zones

Town of Amherst, NY, Land Uses

The town has abundant open space that provides habitat for deer.

Multi-year record of DVA’s• DVAs 1991-2000

• Total: 3295 DVAs

• Raw data difficult (or impossible) to assess visually.

Deer Population Counts• Aerial late winter

counts by natural resource agency using visual polygons

• Displayed here as densities (standardized to area)

Population Counts by Year

• Highest population in 1994 before lethal control took effect [statistically significant]

• 625 deer killed by bait and shoot and nuisance permits (1994-1996)

• 2001 count higher than 1998 [statistically significant]

POPULATION COUNT

0

200

400

600

800

1000

1200

1994 1995 1996

1997 1998 2001

Yearly Deer Population Counts

Population Densities by Management Zone

Before During After

Before, During, and After Lethal Control

When do most collisions occur?

• Time of Day?

• Month?

DVAs by Time of Day

• Most accidents occur in evening and night

NUMBER DVAs

0100200300400500600700800

EARLY MORNING MID-MORNING

AFTERNOON EVENING

NIGHT LATE NIGHT

DVAs by Time of Day

DVAs by Month• Highest number of

collisions occur in the fall and early winter

NUMBER OF DVAs

0100200300400500600700

JAN FEB MAR

APR MAY JUN

JUL AUG SEP

OCT NOV DEC

DVAs By Month

Nearly 1/2 of all collisions occur in the fall

Where do most collisions occur?

• In which parts of town?

• In relation to what features and land uses?

Density of DVA’s by Management Zone

More accidents in the rural parts of town where development and ample open space are intermixed.

DVA Density Correlations

+ Open land

+ Deer population

+ 45 mph roads

– Businesses

– Single residences

– 35 mph roads

– Road density

Examined by Management Zone

+ –

DVA Density within 1/4 Mile of Parks

To deer, all parks are not equal.

Even some small parks have a high density of DVAs nearby

DVA “Hot Spots” 1991-2000

Calculated DVAs/square mile (using density function in ArcView Spatial Analyst®)

Most accidents concentrate where development and open space interface.

“Hot Spots” and Land Uses

•Parks and open space may influence movement patterns

•High traffic volume also plays potential role.

•New development appears to exacerbate the problem

Detailed View of “Hot Spot”

A mixture of land uses typifies most “hot spots.”

Typical “Hot Spot” Land Uses

A mixture of land uses with about 50% open land and most of the rest developed

Typical Non - “Hot Spot” Land Uses

Areas without “hot spots” differ in land uses

They are dominated by development or by open land

MZ1

MZ3

MZ6

Effects of Lethal Control On “Hot Spots”Before After

Urban “Hot Spot”Combination of:

•Deer Habitat (green space, office parks, and vacant land)

•New development (displacing deer)

•High people density

DVA Management PlanINTEGRATED AND ADAPTIVE

TWO FOCI:Whole Town“Hot Spot”

THREE APPROACHES:Influence Human BehaviorInfluence Deer BehaviorAffect Deer Population

Support Management Actions with Data

•Avoid lawsuits

•Support environmental assessments

•Inform adaptive management plans

Use data to...

Whole Town Focus

• Public education (press releases, pamphlets, posters)

• Drivers’ education

• Enforce or enact “no deer feeding” laws

• Encourage use of nuisance permits

• If needed, enact professional lethal control

“Hot Spot” Focus

• Deploy seasonal warning signs

• Facilitate press and media coverage of sign deployment and “hot spots”

• Enforce speed limits in areas of “hot spots”

• Fence and/or improve roadside visibility with brushing at selected corridor “hot spots”

Management Zones Facilitate Implementation

Management ZoneDescription

Suggested Actions

Primarily developed Public educationMixture of open anddeveloped lands

Public education. Target “hot spots” with signage and

speed control Lethal control on nearby open lands

Mostly open land Public education Monitor area for “hot spots” Target “hot spots” with signage and

speed control Use of nuisance permits on

agricultural lands

“Hot Spot” Warning Sign• Novel sign

• Seasonally deployed during high crash period

• Deploy at selected “hot spots”

Sign from Kent County, MI

Challenges in Assessing Results

• Small sample sizes

• Lack of independence

• Variability in deployment sites

Difficulty in conducting statistical tests has been a perpetual problem in testing of warning reflectors

Information Wish List• DVA database for theme

GeoreferencedDriver data (age, gender)Time (24 hours, date)

• Road (type, speed limit)

• Land use (including potential deer habitat)

• Development locations

• Natural features (streams, lakes, hills)

• Deer population counts or estimates

Monitoring Suggestions• Need ongoing multi-year data on deer populations

and DVAs

• Summarize changes in patterns with GIS spatial analysis

• Visually examine changes in locations and intensities of “hot spots”

• Statistically test for significant changes in DVA and population numbers when possible

• Monitor health of vegetation in parks

Ultimate GoalTo coexist with deer