Acoustic location of conspecifics in a nocturnal bird: the corncrake Crex crex

Abstract

Although the use of sounds in spatial orientation is widespread among animals, only a few groups advanced such specific adaptations as echolocation. In contrast, practically all animals and night-active species in particular, must occasionally orient themselves relative to invisible but audible objects such as a hidden rival or predator. In this study, I would like to determine the impact of locating which involves the use of acoustic parameters of sender’s vocalisations by receivers and changes of positions and triangulation of sender’s vocalisations by receivers in estimating the distance to the sender during night-time territorial interactions of the corncrake (Crex crex). Males were subjected to two kinds of stimuli: approaching one, imitating the change of the distance of the calling intruder toward the focal male while keeping the direction constant, or stationary stimuli, involving acoustic stimulation with no motion. Although males subjected to approaching stimulation moved longer distances, in both stimuli groups, males moved predominantly toward or out of the playback speaker, and only occasionally made sideway movements. However, the results gave no evidence of corncrakes moving specifically in order to locate the source of the sound; they suggest that males moved toward or away from the already located sound. The fact that males moved longer distances in response to approaching than stationary stimuli indicates that they were able to perceive the change of the distance to the playback speaker based only on structural parameters or amplitude of the calls played.

Continental‐scale patterns of pathogen prevalence: a case study on the corncrake

“… 2001 ), so the overall pool of host species may exhibit the same pattern, thus influencing parasite transmission. Moreover, corncrake males tend to aggregate on specific calling sites during the breeding season (Budka and Osiejuk 2013 ; Ręk 2014 ) and such behaviour certainly favours density-dependent pathogen transmission. Furthermore, although we do not have direct measures of local density, the large populations of corncrakes in Eastern Europe should result in much higher within-patch local densities or higher densities of such breeding areas, than in Western Europe, both of which would facilitate transmission of haemosporidian parasites.…”

Acoustic localization of terrestrial wildlife: Current practices and future opportunities

“…Software should be open‐source such that it is able to be peer‐reviewed and freely modified by expert users. Notably, only 17 studies reported using open‐source or published localization software (Campbell & Francis, 2012; Hedley et al, 2017; Hedwig et al, 2018; Kershenbaum et al, 2019; Kojima et al, 2016, 2017; Matsubayashi et al, 2017; Papin et al 2018; Park & Kotun, 2018; Rek, 2014; Spillmann et al, 2017; Suzuki et al, 2017, 2016, 2018; Wijers et al, 2019; Wilson et al, 2014; Wilson & Bayne, 2018).…”