Identifying the species causing your damage is the first practical step in reducing it. Bioacoustic deterrents work by broadcasting distress and alarm calls that a particular species already recognizes as danger — so the profile has to match the bird. Generic noise carries no information, and the wrong profile gets you a fraction of the result.
Use the guide below to narrow it down. If you’d rather not guess, photograph the birds and send the picture to us — a Bird Gard specialist will identify the species and build the sound profile at no charge.
How to identify the bird causing your damage
Four observations usually settle it:
- Flock size and behavior. Are you seeing a handful of large birds, or clouds of small ones? Flocking species and solitary raiders call for different coverage strategies.
- What they’re eating, and which part. Whole fruit removed, pecked and abandoned fruit, seed heads stripped, or nuts dislodged and dropped — each points to a different culprit.
- Where they sit between feeds. Tree lines, power lines, rooftops or inside the crop canopy itself.
- Time of day. Most crop damage happens in the dawn and dusk feeding windows.
Note that damage often comes from more than one species, and the mix shifts as the season progresses. It’s worth re-checking mid-season rather than assuming April’s bird is July’s bird.
Common nuisance species
European starlings
Stocky, short-tailed, dark birds with a metallic sheen and pale speckling in winter plumage; they move in dense, coordinated flocks. Starlings feed on fruits, grains and livestock feed, and their droppings can spread diseases such as histoplasmosis. Flocks can number in the hundreds of thousands.
An estimated 200 million European starlings live in North America (USDA National Invasive Species Information Center), which makes them a primary target species for Bird Gard.
Typically affects: vineyards, orchards, berries, grain, dairy and feedlots.
Blackbirds (including red-winged blackbirds)
Large flocking birds that hit grain and fruit crops hard — corn, rice and sunflowers in particular — and contaminate harvested produce with droppings.
Blackbirds cause approximately $150 million in agricultural damage annually (USDA).
Typically affects: corn, rice, sunflowers, small grains.
Crows and ravens
Large, all-black, highly intelligent birds — ravens are noticeably bigger with a heavier bill and wedge-shaped tail. Beyond raiding corn, nuts and fruit, they damage irrigation lines, which can run into thousands of dollars in materials and labour to repair. They also scavenge livestock areas.
Their intelligence is exactly why predictable deterrents fail against them. A California Department of Food and Agriculture field project on crows in almonds recorded strong results in Fresno County, where damage was held to $4.40 per acre — but in one Yuba County block, habituation caused crow numbers and damage to climb by late August, with losses in that block reaching $70.06 per acre (CDFA Vertebrate Pest Control Research Advisory Committee, 1999 field trials).
Typically affects: almonds and tree nuts, corn, fruit, irrigation infrastructure.
Robins
Familiar orange-breasted thrushes that feed on strawberries, blueberries and other small fruit. Robins are difficult to deter visually because they work inside the crop canopy rather than above it, and they nest early in spring.
Typically affects: berries, cherries, soft fruit. Under-canopy speaker placement matters here.
Sparrows
Small, brown, highly gregarious birds. With nearly three dozen species in North America, sparrows form sizeable flocks that feed on grains and fruit crops such as wheat, barley and cherries, and contaminate stored grain with droppings.
Typically affects: grain, stored product, food processing facilities, cherries.
Cedar waxwings
Sleek, crested, fawn-coloured birds with a black mask and waxy red wingtips, almost always seen in tight flocks. They strip soft fruit — cherries, berries and grapes — quickly and in numbers.
Typically affects: cherries, berries, vineyards.
Grackles
Long-tailed, glossy iridescent blackbirds with pale eyes. They feed heavily on cornfields and fruit orchards and form large roosts near urban areas, creating noise and sanitation problems.
Typically affects: corn, orchards, commercial and urban-adjacent sites.
Finches
Small seed-eating birds drawn to seed crops. Sunflower fields and grain storage areas are especially vulnerable, as finches both consume and scatter seed.
Typically affects: sunflowers, seed crops, grain storage.
Magpies
Unmistakable black-and-white birds with long iridescent tails. They scavenge animal feed and can contaminate feed supplies and spread pathogens around livestock operations.
Typically affects: livestock and dairy, feed storage.
Seagulls
Scavenge around ports, fishing docks and coastal landfills, contaminating catches with droppings and spreading waste.
Typically affects: marine and port facilities, landfills, food processing.
Swallows
Small, fast, forked-tail aerial feeders that nest on structures. Their nesting near airport buildings and flight paths raises bird-strike risk during takeoff and landing.
Typically affects: aviation, commercial buildings.
Waterfowl
Ducks, geese and swans graze rice paddies and other wetland crops and degrade water quality in reservoirs and irrigation systems.
Typically affects: rice, wetland crops, reservoirs, parks and turf.
Woodpeckers
Drill into wooden utility poles and structures, weakening them over time and driving costly replacement.
Typically affects: utilities and power infrastructure, timber structures.
Why species identification changes the outcome
A distress call is the sound a bird makes when it is caught or in danger; an alarm call is the shorter warning it gives on spotting a threat. Other birds of the same species read those signals as reliable information that a place has become dangerous — and they respond because fleeing a false alarm costs a few seconds of feeding, while ignoring a real one is fatal.
That information only transmits if the call belongs to the species you’re dealing with. It’s also why ultrasonic devices don’t work: USDA-APHIS Wildlife Services places most bird hearing in the 1,000 to 3,000 Hz range and concludes that because this does not include ultrasonic frequencies, ultrasonic devices will not scare birds (Seamans & Gosser, 2016, USDA-APHIS Wildlife Damage Management Technical Series).
Read more on what bioacoustic bird control is and what the research shows, or browse targeted birds and crops protected.
Not sure what you’re looking at?
Send us a photo and we’ll identify it. Call 541.549.0205 or ask a bird control advisor.