title: High proportion of male faeces in jaguar populations.
abstract: Faeces provide relevant biological information which includes, with the application of genetic techniques, the sex and identity of individuals that defecated, thus providing potentially useful data on the behaviour and ecology of individuals, as well as the dynamics and structure of populations. This paper presents estimates of the sex ratio of different felid species (jaguar, Panthera onca; puma, Puma concolor; and ocelot/margay, Leopardus pardalis/Leopardus wiedi) as observed in field collected faeces, and proposes several hypotheses that could explain the strikingly high proportion of faeces from male jaguars. The proportion of male and female faeces was estimated using a non-invasive faecal sampling method in 14 study areas in Mexico and Brazil. Faecal samples were genetically analysed to identify the species, the sex and the individual (the latter only for samples identified as belonging to jaguars). Considering the three species, 72.6% of faeces (n = 493) were from males; however, there were significant differences among them, with the proportion from males being higher for jaguars than for pumas and ocelots/margays. A male-bias was consistently observed in all study areas for jaguar faeces, but not for the other species. For jaguars the trend was the same when considering the number of individuals identified (n = 68), with an average of 4.2±0.56 faeces per male and 2.0±0.36 per female. The observed faecal marking patterns might be related to the behaviour of female jaguars directed toward protecting litters from males, and in both male and female pumas, to prevent interspecific aggressions from male jaguars. The hypothesis that there are effectively more males than females in jaguar populations cannot be discarded, which could be due to the fact that females are territorial and males are not, or a tendency for males to disperse into suboptimal areas for the species.
authors.affiliation: Department of Conservation Biology, Estación Biologica de Doñana, CSIC, Sevilla, Spain. ffpaloma@ebd.csic.es
authors.forename: Francisco
authors.initials: F
authors.lastname: Palomares
authors.forename: Séverine
authors.initials: S
authors.lastname: Roques
authors.forename: Cuauhtémoc
authors.initials: C
authors.lastname: Chávez
authors.forename: Leandro
authors.initials: L
authors.lastname: Silveira
authors.forename: Claudia
authors.initials: C
authors.lastname: Keller
authors.forename: Rahel
authors.initials: R
authors.lastname: Sollmann
authors.forename: Denise Mello
authors.initials: DM
authors.lastname: do Prado
authors.forename: Patricia Carignano
authors.initials: PC
authors.lastname: Torres
authors.forename: Begoña
authors.initials: B
authors.lastname: Adrados
authors.forename: José Antonio
authors.initials: JA
authors.lastname: Godoy
authors.forename: Anah Tereza
authors.initials: AT
authors.lastname: de Almeida Jácomo
authors.forename: Natália Mundim
authors.initials: NM
authors.lastname: Tôrres
authors.forename: Mariana Malzoni
authors.initials: MM
authors.lastname: Furtado
authors.forename: José Vicente
authors.initials: JV
authors.lastname: López-Bao
mesh_terms: D000818:Animals; D001938:Brazil; D003672:Defecation / Q000502:physiology; D005243:Feces; D045989:Felidae / Q000378:metabolism / Q000502:physiology; D005260:Female; D008297:Male; D008800:Mexico; D046009:Panthera / Q000378:metabolism / Q000502:physiology; D011153:Population; D011156:Population Density; D046011:Puma / Q000378:metabolism / Q000502:physiology; D012744:Sex Ratio; D013045:Species Specificity