Comparison of vocalisations of introduced European red deer stags (Cervus elaphus) in north-western Patagonia (Argentina) with native European populations

Abstract

Polygynous deer are very vocal species, producing calls in various contexts. Male rutting calls in red deer (Cervus elaphus) have been most studied in captive and/or free-ranging European populations. The recent application of ‘source-filter theory’ has identified the independent roles of fundamental frequency (F0) and formants in the production of deer calls and demonstrated the relation between formant spacing and anatomical characteristics such as body size. The present paper describes and characterises the acoustical properties of male rutting vocalisations for a free-ranging red deer population located in the ecotone of the eastern Andean cordillera within the Nahuel Huapi National Reserve (Neuquén, Argentina), and is the first acoustic study of free-ranging red deer stags outside their historic distribution. Recordings were made of seven identified and several unidentified stags at the peak of the rut in 2007. Calculated F0 was found to be higher for these identified stags than for Scottish red deer on the island of Rhum. The analysis of formant spacing was used to calculate the length of the vocal tract (VTL) for the seven males studied; values were comparable to those found in stags from Rhum. The longest calculated VTLs within these males corresponded to those of the four stags with the largest antler racks and the only stags holding harems. Previous studies have shown that VTL correlates with body size, age and reproductive success and that these deer have the ability to lower their larynx and extend their vocal tracts to a maximum, which is probably under sexual selection. Our data fit with this explanation. The higher F0s recorded in this population may result from the influence of wapiti genes, known to be present in these deer, because wapiti have a much higher-frequency rutting call, namely, the bugle. Alternatively, they may be related to the mating strategy, which differs substantially from the northern European populations.

Vocal anatomy, tongue protrusion behaviour and the acoustics of rutting roars in free‐ranging Iberian red deer stags (Cervus elaphus hispanicus)

“…Similarly high f 0 values (ranging from 170 to 300 Hz according to the presented spectrograms) were found in the roars of rutting red deer stags of the Cansiglio Forest (NE Italy; Favaretto et al 2006). The f 0 values in the roars of Austrian ⁄ Hungarian red deer, which were introduced to Argentina at the beginning of the 20th century, ranged from 116 to 140 Hz (Hurtado et al 2011), i.e. they were lower than in C. e. hispanicus (this study) but higher than in C. e. scoticus (Reby & McComb, 2003a).…”

“…2006). The f 0 values in the roars of Austrian/Hungarian red deer, which were introduced to Argentina at the beginning of the 20th century, ranged from 116 to 140 Hz (Hurtado et al. 2011), i.e.…”

Blood proteins of red deer introduced to Patagonia: genetic origins and variability

“…23 Finally, a recent analysis of vocalisations found higher fundamental frequencies in our population as compared with Scottish deer which was suggested to relate to wapiti genes in this populations. 24 Body and antler size are a 'proxy' for general performance; in the present case, the adaption of red deer to the Patagonian environment but constrained by their genetics. Liveweights of free-ranging females living in national parks were up to 145 kg, whereas males were 300 kg and more, corroborated by antlered heads frequently weighing 11-12 kg, and up to 13.6 kg (Fig.…”