Wildlife Services

Protecting People 

Protecting Agriculture 

Protecting Wildlife

National Wildlife Research Center

FY 2017

Economic Research of Human-Wildlife Conflicts:

Methods and Assessments

Contact Information:

Dr. Stephanie Shwiff 

Supervisory Research Economist 

NWRC Headquarters 

4101 LaPorte Avenue 

Fort Collins, CO 80521 

Phone: (970) 266-6150 

Fax: (970) 266-6089 

E-mail:

stephanie.a.shwiff@aphis.usda.gov

Web site: www.aphis.usda.gov/

wildlifedamage/nwrc/

Groups Affected:

Agricultural producers

International wildlife conservation

organizations

State county agricultural

commissioners

State game and fish agencies

State natural resource agencies

State public health agencies

Wildlife Services managers

U.S. citizens

Major Cooperators:

California Department of

Agriculture, Vertebrate Pest

Control Research and Advisory

Committee

Colorado State University

Cornell University

Global Alliance for Rabies Control

Michigan State University

Ontario Ministry of Natural

Resources, Canada

Texas A&M University

Texas Department of State Health

Services

The Ohio State University

University of Hawaii

USDA National Rabies

Management Program

WS Operations 

National Wildlife Research Center Economists Use Benefit-Cost Analyses to Quantify Economic

Impacts of Human-Wildlife Conflicts

The Wildlife Service's (WS) National Wildlife Research Center (NWRC) is the only Federal research

organization devoted to resolving human-wildlife conflicts through the development of effective,

selective, and socially responsible methods, tools and techniques. 

Economic assessments of management tools and techniques, as well as cost estimates for a variety of

wildlife damage issues remain an important need of wildlife managers. Economics research at NWRC

seeks to meet this need and to satisfy The Government Performance and Results Act of 1993 by

acquiring accounting-type, outcome-based data of program efficiency. 

NWRC economists conduct research to determine the potential benefits (savings) and costs involved in

reducing the impacts of introduced invasive species, emerging wildlife-transmitted diseases, and

traditional wildlife-caused damages to agriculture, property, and natural resources, as well as wildlifeposed risks to public health and safety.

Applying Economic Expertise to the Challenges of Wildlife Damage Management

Feral Swine Damage Costs $190M Annually. — In 2015, NWRC partnered with the National

Agricultural Statistics Service to survey more than 9,500 producers about feral swine damage to crops

in 11 states: Alabama, Arkansas, California, Florida, Georgia, Louisiana, Mississippi, Missouri, North

Carolina, South Carolina, and Texas. Approximately 4,300 producers of corn, soybeans, wheat, rice,

peanuts and sorghum responded to the survey. Results showed that peanut and corn farmers in the

Southeast and Texas experienced the highest yield loss from feral swine. However, the economic

burden from feral swine was not limited to just crop damage. Producers also spent a great deal on

damage management and control costs. Many growers reported using a suite of control methods

including shooting and trapping. The costs of employing control measures, as well as losses in yield,

were substantial for crop producers, many of which typically operate on very small profit margins.

Survey results indicate that feral swine damage to crops exceeds $190 million in the United States

annually. Though large, this number likely represents only a small fraction of the total damage by feral

swine because it includes damage to only six crops in the 11 surveyed states.

Modeling Economic Impacts of Cormorants to a Recreational Fishery. — The double-crested

cormo¬rant population in the Great Lakes region increased from 32,000 breeding pairs in the 1970s to

more than 226,000 pairs in the 1990s. This is good news for the birds, but the impacts, if any, to the

economy in the region are still being explored. NWRC economists looked at the costs associated with

reduced fishing oppor¬tunities and nonresident angler tourism spending (i.e., licenses, lodging, food,

gas) in the Oneida Lake region of New York. The overall cost estimate was based on the assumption

that real and perceived cormorant impacts on fish stocks play a role in the number of nonresident

fishing licenses sold. Fewer licenses mean fewer anglers around to spend money. Researchers used

an IMPLAN model to create a mathematical representation of the regional economy, including all the

links among economic sectors (e.g., agricultural, retail, service, manufacturing, and industrial). The

model allowed them to estimate the total economic impact of cormorant damage to the fisheries.

Results showed that the economic loss was on average $5 million to $66 million per year, as well as 66

to 929 job-years annually from 1990 to 2009. This approach to calculating wildlife dam¬age's economic

impacts can be applied to other wildlife to provide a more accurate estimate of total economic impacts.

Economic Impacts of Birds to Sweet Cherry Production. — The United States is the world's

second-largest cherry producer, accounting for 15 percent of the world's total cherry production. Bird

damage is a common and costly problem for cherry and other fruit producers. In 2012, NWRC

economists used survey data from producers in five U.S. States to estimate bird damage to sweet

cherry (Prunus avium) crops with and without the use of bird management. Respondents reported

American robins and European starlings as the most damaging bird species. Growers also reported

using bird management methods such as repellents, shooting, trapping, exclusion netting, and scare

United States Department of Agriculture 

Animal and Plant Health Inspection Service
The U.S. Department of Agriculture is an equal opportunity employment provider and employer

devices; they identified shooting and exclusion netting as the

most effective methods. By producers' estimates, average yield

loss due to bird damage was 13 percent. Using bird management

methods reduced losses by about 21 percent. For those who did

not manage bird damage, yield losses increased by a predicted

26 percent. 

To put this in larger context, the economists applied a model to

the survey data to estimate changes in cherry production costs

when bird management is absent. Results showed that a lack of

bird damage management increases the cost of cherries to

society by as much as $238 million in the short-term and, as

producers and consumers adjust to the new market over time,

reach $29 million in the long-term, annually.

Benefits and Costs of Disease Management. — Disease

transmission at the wildlife-livestock interface can significantly

impact human health, threaten global trade and tourism, cause

significant economic loss, and provide a potential mechanism for

bioterrorism. Yet, given budget limitations, resource managers

often must seek to maximize the benefits and minimize the costs

of disease mitigation efforts. To address this issue, NWRC, APHIS

Veterinary Services, and Texas A&M University researchers and

economists developed a benefit-cost analysis decision

framework. It helps managers make informed choices about

whether and how to target disease management efforts in wildlife

and livestock populations. 

Specifically, the framework offers a way to identify, assemble, and

measure the components that are most vital to animal disease

mitigation efforts. Benefits or damages avoided cover such areas

as consumption demand, human health, livestock production, and

wildlife losses. Costs include not only the operational costs of

disease mitigation, but also the impacts of disease spillover, such

as reduced agricultural production or lost recreational

opportunities. The framework can also be applied to commercially

raised and free-ranging species at various levels of management

—from detailed intervention strategies to broad programmatic

actions. The ability of the framework to illustrate the benefits of

disease management projects per dollar spent helps managers

evaluate their options. This framework is useful to natural

resource managers who wish to maximize financial and other

returns invested in wildlife and livestock disease management

programs.

High Cost of Canine Rabies. — The World Health Organization

estimates that, on average, about 60,000 people die of rabies

each year, and 99 percent of these deaths are attributable to

canine rabies in Asia and Africa. To provide a more com¬plete

assessment of canine rabies' global impact, NWRC economists

extended current economic estimates to include the cost of

human death risk. Human death risk is quantified by how much

people are willing to pay to reduce their chances of dying or,

conversely, how much people must be paid to tolerate increased

risk. Researchers also accounted for both direct and indirect costs

of rabies post-exposure prophylaxis, dog vaccination and control,

rabies diagnostic testing, and cattle deaths. Using computer

simulation models, they estimated the global burden of canine

rabies to be about $124 billion per year. The results also

highlighted important regional differences. Researchers found that

the global burden from canine rabies falls most heavily on Asia,

which accrues more than 80 percent of the nonhuman death

costs. Africa, on the other hand, accounts for only 3 percent of

nonhuman death costs but 45 percent of human deaths. This

study illustrates the potential benefits of canine rabies elimination

and provides an important benchmark for comparing rabies

elimination campaign costs.

Selected Publications:

Anderson, A. and S.A. Shwiff. 2015. The cost of canine rabies on

four continents. Transboundary and Emerging Diseases 62:446-

452. doi: 10.1111/tbed.12168.

Anderson, A., C. Slootmaker, E. Harper, J. Holderieath, and S.A.

Shwiff. 2016. Economic estimates of feral swine damage and

control in 11 US states. Crop Protection 89:89-94. doi:

10.1016/j.cropro.2016.06.023. 

Elser, J.L., A. Anderson, C.A. Lindell, N. Dalsted, A. Bernasek,

and S.A. Shwiff. 2016. Economic impacts of bird damage and

management in U.S. sweet cherry production. Crop Protection

83:9-14. doi: 10.1016/j.cropro.2016/01/014. 

Shwiff, S.A, K.A. Kirkpatrick, T.L. DeVault, and S.S. Shwiff. 2015.

Modeling the economic impacts of double-crested cormorant

damage to a recreational fishery. Human-Wildlife Interactions

9(1):36-47. 

Shwiff, S.A., S.J. Sweeney, J.L. Elser, R.S. Miller, M.L.

Farnsworth, P. Nol, S.S. Shwiff, and A.M. Anderson. 2016. A

benefit-cost analysis decision framework for mitigation of disease

transmission at the wildlife-livestock interface. Human-Wildlife

Interactions 10(1):91-102.

Major Research Accomplishments:

WS economic studies showed feral swine damage to six crops

(corn, soybeans, wheat, rice, peanuts and sorghum) in 11

surveyed states exceed $190 million annually.

WS research estimated the total economic impact of doublecrested cormorant damage to the Oneida Lake region of New

York was $5 to $66 million annually.

WS economic analyses showed that in the absence of bird

damage management, sweet cherry production costs increase as

much as $29 million annually.

WS and partners developed a benefit-cost analysis decision

framework to help managers make informed choices concerning

wildlife and livestock disease mitigation efforts.

WS economists estimated the global burden of canine rabies

to be about $124 billion per year.