Assessment of Bird Damage Assessment of Bird Damage to Sunflower and Corn to Sunflower and Corn

in North Dakotain North Dakota

Megan Klosterman1 , George Linz2 , Tony Slowik3, and William Bleier1

1 Department of Biological Sciences, NDSU 2 USDA, Wildlife Services, National Wildlife Research Center, Bismarck

3 USDA, PPQ, Bismarck

Production

• North Dakota: Top Sunflower Producer– Supports a $906 million economy.

• Corn acreage has increased.• Damage contributed to a reduction in

sunflower crop.

Blackbirds• Population

– Red-winged Blackbird– Yellow-headed Blackbird– Common Grackle– Surpasses many other states

• Prime habitat• Migration flyway• Food distribution

+ +

Increase Increase Constant

=

Increase in Blackbird PopulationIn North Dakota

Study Area

• Prairie Pothole Region (PPR)– 36,800 mi2

– North Central Plains– Large number of wetlands– Migration flyway– Agriculture– Cattail

n

Ralston et al. 2004

Methods

• 120 Sites– 4 mi2 each

• 3 years– 2008, 2009, 2010

• Sites surveyed in August for presence of fields

• Fields surveyed for damage in September

Methods

• 2008, 2009– Surveyed for fields

in center square mile – All corn or sunflower fields

were surveyed for damage.• 2010

– If no fields were in the center, then one random field was chosen within 3 miles of the center.

Methods1st 2nd

1st

2nd

Damage Measurements

Corn 2008 N= 38 Sunflower 2008 N= 14

Corn 2009 N= 30 Sunflower 2009 N= 15

Corn 2010 N = 65 Sunflower 2010 N = 23

2008, 2009, and 2010 Crop Damage

0

0.5

1

1.5

2

2.5

3

2008 2009 2010

Ave

rage

Per

cent

Dam

age

Corn

Sunflower

N= 38

N= 30 N= 65

N= 14

N= 15N= 23

Cost of Damage Statewide

0

2

4

6

8

10

12

2008 2009

Mill

ion

Dol

lars

Corn

Sunflower

N= 38

N= 30N= 14

N= 15

2008, 2009, and 2010 Corn Damage by Strata

0

0.2

0.4

0.6

0.8

1

1.2

SDP NEDP NWDP MCStrata

Ave

rage

Per

cent

Dam

age

2008

2009

2010

N= 30

N= 2

N= 4 N= 2

N= 26N=2

N= 0

N= 2

N= 42

N= 11

N= 6

N= 6

2008, 2009, and 2010 Sunflower Damage by Strata

0

5

10

15

20

25

SDP NEDP NWDP MC

Strata

Ave

rage

Per

cent

Dam

age

2008

2009

2010

N= 1

N= 1

N= 6

N= 3

N= 5N= 11 N= 2 N= 0

N= 2

N= 4

N=13 N= 4

Other

Open Water

Small Grains

Wooded

Sunflower

Beans

Corn

Pasture

Developed

Wetland

Independent Variables

Future Plans: Landcover Analysis

Acknowledgements

• Mario Biondini• Peter Oduor• Jessie Monson• Dereck Stonefish• Jeff Homan• Matthew Strassburg• James Schanandore

Thank You