Visual Responses of Flight-Dispersing Spotted Lanternflies, Lycorma delicatula toward a Tall Vertical Silhouette in a Vineyard

A large accumulation of several hundred actively flight-dispersing spotted lanternflies Lycorma delicatula was found on an isolated single telephone pole in a vineyard in Eastern Pennsylvania, USA. Many of the lanternflies flying across the vineyard very near to the pole turned toward and landed on it in an apparent visually mediated response to the tall vertical silhouette, whereas others flew past it. We video-recorded, digitized, and analyzed 481 tracks, of which there were 188 that were behaviorally classifiable with durations greater than 2 s. We found that lanternflies reacted to the 12.5-m-high pole by turning toward it when they were an average of 2.1 m away from it at an average height of 7.8 m. Those that did not react to the pole by turning toward it were at an average distance of 3.6 m from it at a height of 11.5 m. It appears that the object-vision capabilities of the lanternflies to this vertical structure that were intense enough to elicit a behavioral reaction to it were limited to a mean distance of 2.1 m during in-flight approach.