Effectiveness of Flight Control™ to Reduce Damage to Lettuce Seedlings from Horned Larks

Abstract

Lettuce is an important economic crop in California, with approximately 101,000 ha in production and a value of $1.3 billion in 2002. Bird damage to lettuce in the San Joaquin Valley, the central coast, and southern California is believed to amount to millions of dollars annually. We evaluated the effectiveness of Flight Control ™ (50% anthraquinone applied at 10 L/ha) as a foliar spray for protecting emerging lettuce seedlings from depredation by horned larks. In field enclosure trials conducted near Huron, in the San Joaquin Valley of California, damage to treated lettuce seedlings was 8.5%, compared to 68% damage to untreated seedlings. In a field test, anthraquinone residues on the day of treatment averaged 570 ppm and at Day 50 after treatment were lower than the method of detection (0.063 ppm). However, horned lark numbers using test sites were too low to detect any differences in damage among treated and untreated sites. Anthraquinone offers promise for reducing bird depredations to sprouting lettuce, but additional testing should be conducted to evaluate this repellent in a large-scale field setting.

Repellent Effect of Certain Chemicals Compounds on Wild Birds Attacking Wheat and Cowpea Under Field Conditions

“…York et al (2000) recorded horned lark damage to lettuce seedlings with 60% in Anthraquinone treated and 20% in Mesurol treated, while control plot 100% at enclosure. Cummings et al (2006) referred that horned larks consumed fewer lettuce seedlings treated with flight control (anthraquinone) than untreated seedlings. Birds consumed 8.5% seedlings in the treated enclosures, versus 68.5% seedlings in untreated enclosures.…”

Anthraquinone-based repellent for horned larks, great-tailed grackles, American crows and the protection of California's specialty crops

“…preplant seed treatments, including repellent-treated clay coatings; Cummings et al, 1998) and lettuce seedlings (foliar applications to emergent seedlings) treated with !3000 ppm anthraquinone, (2) great-tailed grackles exposed to ripening melons treated with !2000 ppm anthraquinone and (3) American crows exposed to ripening almonds treated with !3000 ppm anthraquinone. Field efficacy studies for the protection of specialty crops should include independent field replicates with predicted bird damage or bird enclosures within experimental fields (York et al, 2000;Cummings et al, 2006;Werner et al, 2011Werner et al, , 2014b, pre-and at-harvest repellent residues, and bird damage and crop yield measurements. Such field studies are necessary to reconcile efficacy observed under captive and field conditions, and to enable the commercial development of chemical repellents for the protection of agricultural production, including California's specialty crops.…”

“…The purpose of this experiment was to develop an anthraquinone concentration-response relationship for horned larks in captivity. Rather than a foliar repellent application to emergent lettuce seedlings under field conditions (York et al, 2000;Cummings et al, 2006), wheat seeds were selected as the test diet based upon our previous observations of seasonal food selection and energetic requirements of horned larks under captive and field conditions. Thus, this experiment involved concentrationresponse testing among individually-caged horned larks (N ¼ 54) offered whole wheat seeds treated with the Avipel ® Shield repellent.…”

Review of anthraquinone applications for pest management and agricultural crop protection

“…An AQ‐based formulation (50% AQ) sprayed on lettuce seedlings at 10 L ha −1 effectively repelled horned larks within experimental enclosures (i.e. 8.5% damage within treated and 68% damage within untreated enclosures) . However, in a field test of three 1.2 ha test sites sprayed with 10 L ha −1 of an AQ‐based formulation (50% AQ), differences between treated and untreated plots were inconclusive owing to low bird abundance …”