Keyword: territoriality

Dominance relationships in Yangochiroptera: a review

,

Yangochiroptera is a suborder recognized for having diversified food habits and unique social behavior. Based on a literature review, this study analyzed the inter-specific variation present in their social behavior, with an emphasis on dominance behavior. Harem formation, territoriality, and aggressiveness were shown to be connected to dominance behavior. The polygyny of defense of resources and defense of harem females appeared as mating systems in which the possibility of dominance appears to be greater. However, the small number of references dedicated specifically to this type of behavior makes it difficult to describe the patterns, and more studies focusing on the behavioral ecology of their species are needed.

Relações de dominância em Yangochiropteros: uma revisão. Yangochiroptera é subordem reconhecida por apresentar hábitos diversificados em relação à sua alimentação e também aos seus comportamentos sociais únicos. A partir de uma revisão bibliográfica, este estudo buscou analisar a variação interespecífica no comportamento social desse grupo — com ênfase em comportamentos de dominância. Formação de haréns, territorialidade e agressividade mostraram estar conectados ao comportamento de dominância. Já a poliginia de defesa de recursos e de defesa de fêmeas de harém, apareceram como sistemas de acasalamento nos quais a possibilidade da dominância aparenta ser maior. Contudo, o baixo número de referências voltadas especificamente para este tipo de comportamento dificulta a descrição de padrões, sendo necessários mais estudos focados na ecologia comportamental de suas espécies.

Graphical abstract for the article “Dominance relationships in Yangochiroptera: a review” (Luchesi & Parolin, 2023)

Estado actual del conocimiento del roedor fosorial Ctenomys mendocinus Philippi 1869 (Rodentia: Ctenomyidae)

, ,

El género Ctenomys, ampliamente distribuido en América del Sur, comprende más de 60 especies, en su mayoría solo conocidas por su descripción original. Los estudios sobre Ctenomys mendocinus han contribuido de manera significativa al conocimiento de la biología de los tuco-tucos y al esclarecimiento de las relaciones sistemáticas entre varias especies argentinas del género. El presente trabajo resume la información existente disponible sobre este roedor fosorial abarcando distintos aspectos de su sistemática, distribución geográfica, morfología, comportamiento, reproducción, estructura poblacional, territorialidad, sistemas de galerías, estrategias alimentarias y ectoparásitos. Se ha incorporado además información inédita sobre variables corporales y craneales para cada sexo, de ejemplares procedentes de la localidad típica de la especie. La información sintetizada en este trabajo podrá servir de base para futuras investigaciones tendientes a esclarecer los patrones bioecológicos de esta especie y de otras relacionadas, los cuales constituyen una valiosa herramienta para poner a prueba modelos evolutivos propuestos para los roedores subterráneos.

Current knowledge of the fossorial rodent Ctenomys mendocinus Philippi 1869 (Rodentia: Ctenomyidae). The genus Ctenomys, widely distributed in South America, encompasses over 60 species, most of which are only known from their original descriptions. Studies on C. mendocinus have contributed to the knowledge of the biology of tuco-tucos, and to the understanding of the systematic relationships among various Argentinian species of the genus. The present study sums up the existing available information about this fossorial rodent, comprising different aspects of its systematics, geographical distribution, morphology, behavior, reproduction, population structure, territoriality, burrow systems, feeding strategies, and ectoparasites. Furthermore, new information on body and cranial variables for each sex has been included, obtained from specimens of the species’ type locality. The information synthesized in this review will serve as a basis for further research aiming at clarifying the bioecological patterns of this and other related species. These patterns constitute a valuable tool in testing the evolutionary models proposed for subterranean rodents.

Home range, social structure, and scent marking behavior in brown brocket deer (Mazama gouazoubira) in a large enclosure

Social organization and scent-marking behavior were studied in a population of brown brocket deer (Mazama gouazoubira) maintained in an enclosure of 14 ha. The deer were usually solitary (74% of sightings), and individuals of both sexes maintained stable home ranges for periods ranging from two to four years. Home ranges of adult males (4 years old) can be considered exclusive (1–2% overlap); there was no overlap of core areas. Females maintained core areas that were 80% exclusive but had overlapping home ranges. For scent-marking (urination, defecation, forehead rubbing and thrashing) frequency a significant difference occurred between males, females and juveniles (p = 0.002; Kruskal-Wallis test) for total marking frequency and instances of urination/defecation. The location of scent marks also varied with age-sex class. Males marked relatively more frequently outside their core areas, while females and juveniles marked more frequently within their core areas. These differences were also statistically significant (p = 0.04; Kruskal-Wallis test). A limited number of aggressive defenses of these home ranges were observed. Home ranges and core areas of males and females respectively are scent marked extensively.

Área de actividad, estructura social y comportamiento de marcado en corzuela parda en semicautiverio. Se estudió la organización social y comportamiento de marcado en una población de corzuelas pardas (Mazama gouazoubira) mantenidas en un cercado de 14 ha. Las corzuelas generalmente fueron solitarias (74% de observaciones) e individuos de ambos sexos mantuvieron áreas de actividad estables por períodos de entre dos y cuatro años. Las áreas de actividad de los machos fueron esencialmente exclusivas (1–2 % de superposición). Las hembras mantuvieron áreas de actividad intensiva las cuales fueron frecuentemente exclusivas (80%) pero tenían superpuestas las áreas de actividad total. La frecuencia de marcado (orinación, defecación, frotado de la frente y movimientos de la cabeza contra la vegetación) fue significativamente diferente entre machos, hembras y juveniles (p = 0.002; prueba de Kruskal-Wallis), tanto para orinación-defecación como para marcas totales. El lugar de marcado también varió con la edad y el sexo. Los machos marcaron relativamente más frecuentemente fuera del lugar de actividad intensiva y las hembras y juveniles marcaron más frecuentemente dentro de sus áreas de actividad intensiva. Estas diferencias fueron significativas estadísticamente (p = 0.04; prueba de Kruskal-Wallis). Se observaron algunas defensas agresivas. Las áreas de actividad y de uso intensivo en machos y hembras fueron respectivamente marcadas extensivamente con marcas olorosas.

Home ranges of Philander frenata and Akodon cursor in a Brazilian restinga (coastal shrubland)

, ,

Home ranges of Philander frenata (= P. opossum) (Didelphimorphia, Didelphidae) and Akodon cursor (Rodentia, Sigmodontinae) in Barra de Maricá, Rio de Janeiro, were estimated and analysed in relation to sex, age, both dry and wet, and breeding and nonbreeding seasons, and correlated with population densities and body weight. In P. frenata, home ranges were predominantly affected by the breeding season, while in A. cursor they were mostly affected by sex. There was no correlation between body weight and home range size within species. No effects of population densities on home range size were found in both species, but we detected an increase in the number of overlapping points of capture with the increase of population densities. Females of A. cursor presented territoriality while males did not. This seems to be a general behaviour in akodontines. Males would have contact with many females, and females would defend nesting and food resources. In P. frenata, neither females nor males seemed to be territorial, presenting a mating system without permanent
couples.