Tree Hole Utilisation by the Hairy-Eared Dwarf Lemur (Allocebus trichotis) in Analamazaotra Special Reserve

Abstract

In this study we describe tree hole characteristics and use by the hairy-eared dwarf lemur (Allocebus trichotis) to determine habitat needs, potential functions of tree holes and sleeping group composition. We radio-tracked 6 adult individuals between April and November 2007 in the Analamazaotra Special Reserve. Tree holes were 1–9 m high (median: 7 m), in living trees measuring 26–54 cm in diameter at breast height (median: 32 cm), and could be a limiting resource. Each individual used 4 or 5 tree holes and had high nest fidelity. Animals most often slept socially in mixed-sex groups of 2–6 individuals and occasionally shared a tree hole with white-tailed tree rats (Brachytarsomys albicauda). We identified two sleeping groups: one composed of 2 adult males, 2 adult females and 2 juveniles; one composed of at least 2 adult females and 2 juveniles. Although tree holes were generally group exclusive, some intergroup sleeping was observed. Tree holes could have antipredator and thermoregulatory functions. Further research into sleeping hole availability, nest use and the degree of niche separation or competition between sympatric Cheirogaleidae and other tree hole users (e.g. endemic rodents) is needed to assess better the conservation needs of these species.

Characterization of the Tree Holes Used by Lepilemur ruficaudatus in the Dry, Deciduous Forest of Kirindy Mitea National Park

“…Similarly, Galago moholi seeks refuge in tree holes when the ambient temperature falls below freezing [Bearder and Martin, 1980]. The choice of sleeping site for nocturnal primates is also influenced by the height of a tree hole entrance [Hankerson et al, 2007;Lahann, 2007;Deppe et al, 2008;Biebouw et al, 2009]. Entrances for sleeping tree holes used by L. ruficaudatus in Ankoatsifaka were frequently found below canopy level.…”

“…Mature forests, which include large and emergent trees, offer more suitable sleeping sites for arboreal primates than young and secondary forests [e.g., Olivieri et al, 2005;Asensio et al, 2012]. These sleeping sites include leaf nests, tangles, dense vegetation, and tree holes [Garcia and Braza, 1993;Bearder et al, 2003;Rasoloharijaona et al, 2003;Hankerson et al, 2007;Rasoloharijaona et al, 2008;Biebouw et al, 2009;Génin, 2010;Ramanankirahina et al, 2012]. Sleeping tree choice and use have been linked to predation avoidance [Hamilton, 1982] and disease risk [Heymann, 1995].…”

Social variables exert selective pressures in the evolution and form of primate mimetic musculature

“…taxa such as the mouse lemurs. Although these primate species do not form large social groups they still typically come together in mixed sex sleeping groups, a behavior that has been linked to both temperature regulation and safety against predators (Radespiel et al 2003;Rasoloharijaona et al 2008;Biebouw et al 2009). Facial displays have been documented in some of these taxa (e.g.…”

Forest Type Influences Population Densities of Nocturnal Lemurs in Manompana, Northeastern Madagascar

“…Omnivorous lemurs, such as mouse lemurs (Microcebus sp.,), dwarf lemurs (Cheirogaleous sp.,) and hairy-eared lemurs (Allocebus trichotis) have diverse diets, comprising insect secretions, arthropods, small vertebrates, gum, fruits, flowers, nectar, and also leaves and buds (Biebouw et al 2009;Ganzhorn 1988;Lahann 2007;Radespiel 2006;Radespiel et al 2006;Wright and Martin 1995). Mouse lemurs have higher encounter rates in more disturbed regions of Ranomafana National Park (Herrera et al 2011), and in Kirindy forest in western Madagascar, higher numbers were recorded following low-intensity logging (Ganzhorn 1995).…”