Skip to main content

Blackbirds and Starlings in Conflict with Agriculture

Methods Development and Population Biology of Blackbirds and Starlings in Conflict with Agriculture, Concentrated Animal Feeding Operations, and Urban Environments

Research Project

In the United States, European starlings, blackbirds, and crows are abundant and widely distributed, with their winter populations believed to be between 750 million and 1 billion. The estimated annual damage to grain, fruit, and berry crops from these birds exceeds $150 million in direct costs. Additional costs, not estimated, include those spent to prevent human health and safety hazards and those from damage abatement efforts.

photo of blackbird flockOverall blackbird damage to agricultural crops: Blackbirds annually damage >$15 million in sunflower, $15-25 million in ripening corn, $20-50 million in seeded corn, $10 million in ripening cherries, $6 million in sorghum, >$20 million in rice, $4 million in grapes, $1-2 million in blueberries, $1 million in lettuce, and unknown dollars of cereal grains, peanuts, and pecans.

phto fo sunflower head with damageBlackbird damage to sunflower: Large flocks of blackbirds congregate in the northern Great Plains from August to October in preparation for a strenuous migration to southern wintering areas. Blackbirds acquire energy for migration by eating agricultural crops, especially sunflower. Red-winged blackbirds, common grackles, and yellow-headed blackbirds cause most of the damage. Sunflower producers in North Dakota and South Dakota annually lose $4-7 million.

Bird damage to fruit: Blackbirds and European starlings, along with songbirds, consume and damage fruit throughout the United States. In addition to consuming the entire fruit, damage also reduces fruit quality and makes it susceptible to other pests and pathogens. As a result, fruit producers lose tens of millions of dollars each year to birds.

photo of dairy
Blackbird damage to feedlots and dairies: Blackbirds and European starlings also congregate at feedlots and dairies throughout the United States. Large flocks of birds can consume and contaminate feed and may contribute to disease transmission. In addition, accelerated corrosion of fencing, corrals, and other infrastructure can occur due to the birds' acidic fecal matter.

Research under this project focuses on the following:

  • Wildlife repellents - developing bird repellents and application strategies to protect agricultural crops and managing pesticide risk for birds
  • Take models - developing a DRC-1339 mortality model and an allowable take model
  • Wildlife conservation plots - evaluating perennial sunflower plantings for managing blackbird damage to crops
  • Blackbird behavior - studying blackbird movements, migrations, and winter roost locations
  • Wildlife damage at dairies - characterizing and managing wildlife damage at dairies
Project Leader:
Dr. Page E. Klug
North Dakota State University
P.O. Box 6050
Fargo, ND 58108-5060

Project Factsheet: 
Complementary Content