Marking by elytral clip changes stridulatory characteristics and reduces reproduction in the American burying beetle, Nicrophorus americanus

Abstract

Some insects produce and use sound during multiple behaviors including many aspects of reproduction. Variation in call structure depends on the evolved morphological structures used to produce the sound and encode function. Beetles in the genus Nicrophorus produce stridulation by rubbing plectra, located on the ventral side of the elytra, against a pars stridens, located on the caudal end on the fourth and fifth abdominal segment in females and males, respectively. During field surveys for the endangered N. americanus, survey crews have historically used a small V-shaped notch cut in the caudal end of the right elytron to serves as a permanent marking method. No study, however, has examined the effect of this marking technique on the characters of stridulation or consequences for reproductive behavior and fitness. Here we show that one temporal and one spectral character of sound change significantly following elytron clipping, and that reproductive success is significantly decreased in all breedings in which a parent beetle is elytron-clipped. We recommend replacement of this marking technique with non-invasive methods to ensure conservation of this endangered species.