Data for sound comparisons of auditory frightening devices and antipredator responses of nuisance blackbirds

In August 2022, at a recently harvested agricultural field in Foster County, North Dakota, we collected sound attenuation data within the hearing range of blackbirds (Icteridae) for a propane cannon, rifle and shotgun within 500 meters of the detonation point. We also examined the responses (i.e., relaxed, vigilant, startled) of 32 red-winged blackbirds (Agelaius phoeniceus) and 32 brown-headed cowbirds (Molothrus ater) to blasts when placed 15–495 meters from a cannon. The August 2020 study took place on flat terrain in a harvested agricultural field with no vegetative barriers at the North Dakota State University Agronomy Seed Farm in Casselton, North Dakota. Birds were placed in small, individual cages (covered to minimize visual stimuli) and we evaluated startle responses to the impulsive sound of the cannon with two experiments: 1) incremental, where we exposed birds to a series of blasts at decreasing distances and 2) random assignment, where we randomly assigned birds a distance and exposed them to four cannon blasts in quick succession. This data publication contains the data from both studies and the R code used to analyze these data.The study was designed to measure sound attenuation of three tools used as frightening devices (i.e., propane cannon, rifle, and shotgun) at frequencies within bird hearing capabilities and to assess responses of birds to a propane cannon blast as a function of distance, and how responses change with repeated blasts.For more information about this study and these data, see Duttenhefner and Klug (in press).

2022年8月，我们在北达科他州福斯特县一处刚完成收割的农田中，采集了丙烷炮（propane cannon）、步枪与霰弹枪在距爆点500米范围内、符合黑鹂科（Icteridae）动物听觉频率范围的声音衰减数据。同时我们还测试了32只红翅黑鹂（Agelaius phoeniceus）与32只棕头牛鹂（Molothrus ater）在距炮位15至495米处时，对爆炸声的三种反应状态：放松、警觉与受惊。

2020年8月的研究则在北达科他州卡塞尔顿市北达科他州立大学农学种子农场开展，实验场地为无植被遮挡的平坦收割农田。实验中将鸟类安置于小型个体笼舍（笼舍被遮蔽以减少视觉刺激），通过两组实验评估鸟类对丙烷炮脉冲声响的惊跳反应：其一为渐进式实验，即让鸟类依次暴露于距离逐渐缩短的多组爆炸声中；其二为随机分配实验，即预先为鸟类随机分配爆响距离，随后让它们连续快速接受4次丙烷炮爆响。

本数据集包含上述两项研究的全部数据，以及用于数据分析的R代码。本研究旨在测量三类驱吓装置（丙烷炮、步枪与霰弹枪）在鸟类听觉频率范围内的声音衰减情况，评估鸟类对丙烷炮爆响的反应如何随距离变化，以及重复爆响对鸟类反应的影响。

如需了解本研究与本数据集的更多细节，请参阅Duttenhefner与Klug（即将出版）。