European starling, Sturnus vulgaris

Blackbirds and Starlings The term blackbird loosely refers to a group of about 10 species of North American birds, the most common of which are the red-winged blackbird, common grackle, and brown-headed cowbird. The starling, a European species introduced to North America in the late 1800s, superficially resembles native blackbirds and often associates with them. Together, blackbirds and starlings constitute the most abundant group of birds in North America, comprising a combined population of more than 1 billion (Dolbeer and Stehn 1983). Blackbird damage to ripening corn, sunflower, and rice can be serious (Dolbeer 1994). Much of this damage is done in late summer during the milk or dough stage of seed development. The seed contents of corn are removed, leaving the pericarp or outer coat on the cob. Blackbird damage to sprouting rice in the spring can be important in localized areas.

Starling depredations at feedlots in winter can cause substantial losses (Glahn et al. 1983, Besser et al. 1968). Although contamination of livestock feed by starling feces is often a concern of farmers, a study indicated this contamination did not interfere with food consumption or weight gain of cattle and pigs (Glahn and Stone 1984). Starlings can be serious depredators in fruit crops such as cherries and grapes.

Perhaps the greatest problem caused by blackbirds and starlings is their propensity to gather together in large, nocturnal roosting congregations, especially in winter. The noise, fecal accumulation, and general nuisance caused by millions of birds roosting together near human habitations can be significant (White et al. 1985). Roosting birds near airports can create a safety hazard for aircraft. Roost sites, if used for several years, can become focal points for the fungus that causes histoplasmosis.

Summary of Damage Prevention and Control Methods

Exclusion

Close all openings larger than 1 inch (2.5 cm).

Place covering at 45o angle on ledges.

Porcupine wires on ledges or rafters.

Netting to prevent roosting on building beams or to protect fruit crops. PVC or rubber strips to cover door openings; netting where frequent access is not needed.

Cultural Methods and Habitat Modification

Reduce availability of food and water at livestock facilities: remove spilled grain and standing water; use bird-proof feeders and storage facilities; feed livestock in open sheds; where appropriate, feed in late afternoon or at night; lower water level in waterers.

Modify roost sites by closing buildings; exclude from roost areas with netting (for example, under roof beams); modify specific perch sites. For tree roosts, prune branches of specific trees or thin trees from groves.

Frightening

Frightening devices include recorded distress or alarm calls, various sound-producing devices, chemical frightening agents (Avitrol®), lights, and bright objects. Use with fruit crops and starling roosts. Also useful at livestock facilities in warm climates and at facilities located near major roosts.

Repellents=

Soft sticky materials (polybutenes) discourage roosting on ledges. Starling repellent is currently under development: methyl anthranilate (grape flavoring). If successful, it may be useful for protecting fruit and as a livestock feed additive.

Toxicants

Starlicide: toxic bait for use around livestock facilities and, in some situations, at roost sites.

Toxic perches: can be useful for certain industrial and other structural roost situations.

Fumigants

None are registered.

Trapping

Nest-box traps, for use during nesting season.

Decoy traps may be useful around orchards or livestock facilities. Proper care for trap and decoy birds is necessary.

Shooting

Helpful as a dispersal or frightening technique. Not effective in reducing overall starling numbers