Blackbirds, such as red-winged blackbirds (Agelaius phoeniceus), are notorious agricultural pests and damage crops at multiple stages of growth. Our aim was to test a novel deterrent, the use of sound designed to mask communication among birds (termed a “Sonic Net”), to deter blackbirds (Icteridae) from target areas of maturing sunflower crops. The Sonic Net masks communication of a target species by delivering “pink noise” that overlaps with the frequencies that the species uses for acoustic communication. If birds cannot hear predators or conspecific warning calls their perceived predation risk increases, and they relocate to an area with lower predation risk. Working with local sunflower producers in North Dakota, USA we set up experimental sites in three sunflower fields that were actively used by mixed-species blackbird flocks. In each field, we established two 0.2 ha plots and measured the initial area of damage for 63 individually-marked sunflowers. We applied the Sonic Net treatment to one of the paired plots in each field. At the end of the 20-day treatment period, we measured the total area damaged on the individually-marked sunflowers from each plot to calculate the change in damage for each sunflower. In all three fields, Sonic Net treatments substantially reduced percent damage to sunflowers, by 28.6% (95% CI: 12.5–41.7%), 63.6% (57.2–69.0%) and 22.6% (16.6–28.1%) for fields in Burleigh, McIntosh, and Emmons, respectively. In addition, sunflowers with a higher initial area of available seed experienced higher damage. We predict that the effect of the Sonic Net treatment may be greater in other crop phases and types, such as in the establishment phase or ground cover crops. During crop establishment there is a relative lack of tall, three-dimensional vegetational structure, which would allow for more effective spread of the Sonic Net sound and offer fewer physical refugia for birds to lower their perceived predation risk. We suggest both larger scale agricultural tests of the Sonic Net and efficacy tests for protecting crops at early growth stages to further explore the usefulness of this technology for crop protection.

黑鸟，如红翅黑鸟（Agelaius phoeniceus），是臭名昭著的农业害虫，会在多个生长阶段损害农作物。我们的目标是测试一种新颖的威慑力，即使用旨在掩盖鸟类之间的交流的声音（称为“声波网”）来阻止成熟向日葵作物目标区域中的黑鸟（crop科）。Sonic Net通过传递“粉红色噪声”来掩盖目标物种的通信，该“粉红色噪声”与该物种用于声音通信的频率重叠。如果鸟类听不到掠食者或特定警告发出的声音，它们的感知掠食风险就会增加，并且他们会迁移到捕食风险较低的区域。我们与美国北达科他州的当地向日葵生产商合作，在三个向日葵田中建立了试验场所，这些田间被混合物种黑bird群积极利用。在每个字段中，我们建立两个0。在2公顷的土地上，测量了63个带有单独标记的向日葵的初始破坏面积。我们将Sonic Net处理应用于每个字段中的一对配对图。在20天的处理期结束时，我们测量了每个田地上带有单独标记的向日葵的总损坏面积，以计算每个向日葵的损坏变化。在所有三个领域中，Sonic Net处理大大降低了对向日葵的损害百分比，伯利地区的向日葵分别减少了28.6％（95％CI：12.5–41.7％），63.6％（57.2–69.0％）和22.6％（16.6–28.1％） ，McIntosh和Emmons。另外，可用种子的初始面积较高的向日葵遭受的损害也更大。我们预测，在其他作物阶段和类型中，例如在定植阶段或地被植物中，Sonic Net处理的效果可能会更大。在农作物种植期间，相对缺乏高大的三维植被结构，这将使Sonic Net声音更有效地传播，并减少鸟类对身体的抵触感，从而降低其感知的捕食风险。我们建议对Sonic Net进行大规模的农业测试，以及在早期生育阶段保护作物的功效测试，以进一步探索该技术对作物保护的有用性。