Passilongo, D., Reby, D., Carranza, J., Apollonio, M. (2013) Roaring High and Low: Composition and Possible Functions of the Iberian Stag’s Vocal Repertoire. PLoS ONE 8(5): e63841.

We provide a detailed description of the rutting vocalisations of free-ranging male Iberian deer (Cervus elaphus hispanicus, Hilzheimer 1909), a geographically isolated and morphologically differentiated subspecies of red deer Cervus elaphus. We combine spectrographic examinations, spectral analyses and automated classifications to identify different call types, and compare the composition of the vocal repertoire with that of other red deer subspecies.

Iberian stags give bouts of roars (and more rarely, short series of barks) that are typically composed of two different types of calls. Long Common Roars are mostly given at the beginning or at the end of the bout, and are characterised by a high fundamental frequency (F0) resulting in poorly defined formant frequencies but a relatively high amplitude. In contrast, Short Common Roars are typically given in the middle or at the end of the bout, and are characterised by a lower F0 resulting in relatively well defined vocal tract resonances, but low amplitude. While we did not identify entirely Harsh Roars (as described in the Scottish red deer subspecies (Cervus elaphus scoticus)), a small percentage of Long Common Roars contained segments of deterministic chaos.

We suggest that the evolution of two clearly distinct types of Common Roars may reflect divergent selection pressures favouring either vocal efficiency in high pitched roars or the communication of body size in low-pitched, high spectral density roars highlighting vocal tract resonances. The clear divergence of the Iberian red deer vocal repertoire from those of other documented European red deer populations reinforces the status of this geographical variant as a distinct subspecies.

https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0063841&type=printable

Volodin, I., Volodina, E., Frey, R., Carranza, J. & Torres-Porras, J. (2013). Spectrographic analysis points to source-filter coupling in rutting roars of Iberian red deer. Acta Ethol. 16, 57-63. DOI 10.1007/s10211-012-0133-1.

Source filter coupling is the rarest acoustic phenomenon not only in Iberian red deer, but in any mammal. In most mammals, sound production can be well described in the framework of source filter theory. The vocal output is the result of combined work of the larynx (the source) and of the supralaryngeal vocal tract (the filter). The source filter theory suggests the independence of sour ce and filter. Thus, vocal tractfiltering should not affect the fundamental frequency (f0) of the sound created in the larynx. Spectrographically, the source is mostly characterized by the f0 an ditsharmonics,whilethefilter

by the vocal tract resonances, i.e., formant frequencies. Nevertheless, a non-independent (coupled) source and filter can be proposed when the vocal folds start oscillating at one of the formant frequencies. Couplin gbetweensourceandfilterhas been found in human singers and predicted for red deer Cervus elaphus by a computer modeling approach. This study describes different modes of phonation in a natural bout of rutting calls of Iberian red deer Cervus elaphus hispanicus and the transition from a chaotic mode to a probable source

filter coupling mode. This ph enomenon might be involved in the production of extremely high-frequency bugles of North American and Asian subspecies of C. elaphus

https://link.springer.com/content/pdf/10.1007%2Fs10211-012-0133-1.pdf

Torres-Porras, J., Carranza, J., Pérez-González, J., Mateos, C., Alarcos, S. (2013) The tragedy of the commons: unsustainable population structure of Iberian red deer in hunting estates. European Journal of Wildlife Research 60 (2),351–357

Hunting can influence population structure with consequences in ecological and evolutionary processes. Populations of Iberian red deer (Cervus elaphus hispanicus) in Spain occur under two different management regimes: fenced and unfenced (open) estates. We compared census data, hunting bags and data from hunted individuals between both types of estates. Harvest on stags was moderate in fenced estates but strong in open ones, probably due to the competition between neighbouring landowners over the same deer populations. On the contrary, female culling was low in open estates compared to fenced ones. As a result, populations in open estates have mostly young males and strongly femalebiased sex ratios. Female-biased population structure in open estates did not result in higher number of males being harvested per year compared with fenced estates, probably due to negative effects on development, survival and reproduction, and harvested males were younger, and hence, with smaller antlers. There is published evidence for undesirable effects of biased population sex ratio and age structure in these red deer populations. Our results indicate that this type of management may be unsustainable and recommend that harvest on males in open estates should be reduced and that on females increased, in order to maintain a more balanced population structure that may allow sustainable population dynamics and the operation of natural evolutionary processes.

https://link.springer.com/content/pdf/10.1007%2Fs10344-013-0793-9.pdf

Costa, V., Pérez-González, J., Santos, P., Fernández-Llario, P., Carranza, J., Zsolnai, A., Anton, I., Buzgó, J., Varga, G., Monteiro, N., Beja-Pereira, A. (2012) Microsatellite markers for identification and parentage analysis in the European wild boar (Sus scrofa). BMC Res Notes 5, 479

Background

The wild boar (Sus scrofa) is among the most widespread mammal species throughout the old world. Presently, studies concerning microsatellites in domestic pigs and wild boars have been carried out in order to investigate domestication, social behavior and general diversity patterns among either populations or breeds. The purpose of the current study is to develop a robust set of microsatellites markers for parentage analyses and individual identification.

Findings

A set of 14 previously reported microsatellites markers have been optimized and tested in three populations from Hungary, Portugal and Spain, in a total of 167 samples. The results indicate high probabilities of exclusion (0.99999), low probability of identity (2.0E^-13 – 2.5E^-9) and a parentage assignment of 100%.

Conclusions

Our results demonstrate that this set of markers is a useful and efficient tool for the individual identification and parentage assignment in wild boars.

https://bmcresnotes.biomedcentral.com/track/pdf/10.1186/1756-0500-5-479

Pérez-González, J., Frantz, A., Torres-Porras, J., Castillo, l. & Carranza, J. (2012). Population structure, habitat features and genetic structure of managed red deer populations. Eur. J. Wildl. Res. 58, 933–943. DOI 10.1007/s10344-012-0636-0.

Management of game ungulates alters population structure and habitat features, with potential effects on genetic structure. Here, we study 26 red deer (Cervus elaphus) populations in Spain. We used census data and habitat features as well as genetic information at 11 microsatellite markers from 717 individuals. We found that metapopulations presented a distribution associated with forest interruptions. Within metapopulations, fences did not have asignificant effect on red deer genetic structure. The metapopulations we studied presented similar population structure, but they differed in habitat features and genetic structure. The metapopulation with higher resource availability showed a genetic structure pattern in which genetic relatedness between geographically close individuals was high while relatedness between geographically distant individuals was low. Contrarily, the metapopulation with lower resource availability presented a genetic structure pattern in which the genetic relatedness between individuals of different populations was independent of the geographic distance.

We discuss the possible connection between resource availability and genetic structure. Finally, we did not find any population or environmental variable related to genetic dif-ferentiation within metapopulations.

https://link.springer.com/content/pdf/10.1007%2Fs10344-012-0636-0.pdf

Frey, R., Volodin, I., Volodina, E., Carranza, J. & Torres-Porras, J. (2012). Vocal anatomy, tongue protrusion behaviour and the acoustics of rutting roars in free-ranging Iberian red deer stags (Cervus elaphus hispanicus). Journal of Anatomy 220, 271-292.

Roaring in rutting Iberian red deer stags Cervus elaphus hispanicus is unusual compared to other subspecies of red deer, which radiated from the Iberian refugium after the last glacial maximum. In all red deer stags, the larynx occupies a permanent low mid-neck resting position and is momentarily retracted almost down to the rostral end of the sternum during the production of rutting calls. Simultaneous with the retraction of the larynx, male Iberian red deer pronouncedly protrude the tongue during most of their rutting roars. This poses a mechanical challenge for the vocal tract (vt) and for the hyoid apparatus, as tongue and larynx are strongly pulled in opposite directions. This study (i) examines the vocal anatomy and the acoustics of the rutting roars in free-ranging male C. e. hispanicus; (ii) establishes a potential mechanism of simultaneous tongue protrusion and larynx retraction by applying a two-dimensional model based on graphic reconstructions in single video frames of unrestrained animals; and (iii) advances a hypothesis of evaporative cooling by tongue protrusion in the males of a subspecies of red deer constrained to perform all of the exhausting rutting activities, including acoustic display, in a hot and arid season.

https://onlinelibrary.wiley.com/doi/epdf/10.1111/j.1469-7580.2011.01467.x

Carranza, J. & Polo, V. (2012). Is there an expected relationship between parental expenditure and sex ratio of litters or broods?. Animal Behaviour 84, 67-76.

Parents may be selected to adjust the sex ratio of their offspring when parental expenditure yields Different fitness returns from sons and daughters. This prediction is clear when parents produce only one offspring per reproductive attempt, but more complicated when parental resources are shared by several offspring, and parents may potentially influence the resource allocation among offspring as well as their number and sex. Here we present an optimization model to make predictions on how total parental expenditure may relate to the number and sex of offspring at every rank position within the litter or brood as well as the sex ratio of the litter/brood for the case of a large population with stable Fisherian sex ratio. We show that selection for sex ratio adjustment should be stronger for offspring at higher- ranking positions, for which the amount of resources received can be more predictable. Also, the relationship between parental resources devoted to a litter/brood of a given size and the primary sex ratio (proportion of males) is not expected to be a monotonically increasing function but rather a J-shaped relationship, steeper for small litters/broods and more extreme sexual dimorphism. Parental expenditure relates to increased sex ratio only for small variations in parental expenditure and for a given brood/litter size. For variable litter/brood sizes, a general relationship between parental resources and litter/brood sex ratio is not expected, although in practice pooling litters or broods of different sizes may produce negative relationships between parental expenditure and sex ratio of the litter/brood.

https://reader.elsevier.com/reader/sd/pii/S0003347212001650?token=A3CE4809913F0532983B1AC1AD27F546D562911C757499FA01B40367FC3759C4343EC28C3F979A74145C3D0E51AEAEE5

Castillo, L., Fernández-Llario, P., Mateos, C., Carranza, J., Benítez-Medina, J.M., García-Jiménez, W., Bermejo-Martín, F., Hermoso de Mendoza, J. (2011). Management practices and their association with Mycobacterium tuberculosis complex prevalence in red deer populations in Southwestern Spain. Preventive Veterinary Medicine 98, 58-63.

Intensification of game management may increase the prevalence of tuberculosis (TB) in wildlife despite eradication programs implemented in cattle herds in the same areas. In this cross-sectional study, we investigated the association between wild game management practices and the presence of tuberculosis in red deer populations in Southwestern Spain. Five hundred and fifty-one animals were examined by necropsy to detect tuberculosis-like lesions in the main lymph nodes. Prevalence, as determined by TB-like lesions, was estimated to be 5.1% of animals, with 77% of TB-like lesions confirmed by PCR. Our results suggest that population density, in addition to factors which promote the local aggregation of animals, is factors associated with increased prevalence of TB in red deer populations. We suggest that management practices including supplementary feeding, fencing, water ponds and interaction with domestic livestock should be revised in order to prevent TB in wild deer both.

https://reader.elsevier.com/reader/sd/pii/S0167587710003314?token=7EDF61C4B7DA043557A585B2FA347DA6F26C468647B7461AFEB9E3992093A538F652D89B4B962327436DFDD6AFE3E2F8

Pérez-González, J., Carranza, J.,  Mateos, C. (2011) Mothers that produce sons and daughters are genetically different in red deer. Mammalian Biology.  77, 147-150 

Sex ratio theory, and in particular Fisher principle, assumes parental control over the sex of offspring through the action of autosomal genes with Mendelian segregation. In spite of the importance of Fisher’s principle in evolutionary biology, the number of studies looking for possible loci involved in sex ratio bias is, at best, very low. Newly developed genetic tools frequently allow evolutionary biologists to manage genetic data. Here we encourage the application of association tools to databases that include genetic information for autosomal loci and offspring sex to improve our knowledge on sex ratio evolution. As an example we use microsatellite markers to scan autosomal chromosomes and look for linked genetic regions associated with offspring sex in red deer (Cervus elaphus). We found a microsatellite marker (CelJP38) mapped in chromosome 27 for which females producing sons and daughters were genetically different. To the best of our knowledge, this is the first study that shows a genetic signal that points out an association between mother genotype and offspring sex in natural populations of a mammal.

https://link.springer.com/article/10.1016/j.mambio.2011.07.006

Pérez-González, J. & Carranza, J. (2011). Female aggregation interacts with population structure to influence the degree of polygyny in red deer. Animal Behaviour 82, 957-970.

In polygynous systems, female aggregation may affect the degree of polygyny by increasing the variance in male mating success. However, other population features such as the sex ratio and the age structure of males may also affect the distribution of male mating success. We combined behavioural observations and genetic data to investigate the relationship between spatial distribution, population structure and degree of polygyny in 30 red deer, Cervus elaphus, populations in Spain. We found that although female aggregation was positively related to mean harem size, under conditions of high female aggregation males were unable to monopolize whole female groups. The relationships between female aggregation and behavioural estimates of the variance in male mating success were strongly influenced by the sex ratio and the proportion of competitive males in the population. Potential skew of male mating success and potential opportunity for sexual selection were higher in adults than in young or subadult males. Finally, the behaviourally estimated distribution of male mating success matched the genetically estimated degree of polygyny, especially under conditions of relatively high synchrony in female receptivity. Our results show how population structure can interact with female aggregation in space and time to influence the opportunity for sexual selection in red deer.

https://reader.elsevier.com/reader/sd/pii/S0003347211003034?token=7E36E243B0CF2710A92294323F02D33F39AB23D4E9BAB1BF48CED463B1A5D5130C02EE1F02CF31A1AFC870DA5F28AEC9