Leaf nest use and construction in the golden‐brown mouse lemur (Microcebus ravelobensis) in the Ankarafantsika National Park

Abstract

The use of leaf nests has been documented in several mouse lemur species over the last few decades, including the golden-brown mouse lemur. Nest construction, however, has only rarely been observed and detailed descriptions of this process are lacking so far. We aim to determine the relative importance of leaf nests as shelters for the golden-brown mouse lemur, and to test predictions concerning the role of thermoregulation, safety (i.e., protection of infants), and of interspecific competition with the sympatric gray mouse lemurs in regulating nest use. Finally, we intend to clarify whether and how Microcebus ravelobensis constructs the nests, and we provide physical descriptions of seven leaf nests. Nocturnal focal observations were carried out from May 2007 to January 2008 on 18 females, and sleeping sites were regularly monitored during a six-month period. Data were collected from two study sites, one with exclusive presence of M. ravelobensis, and one with co-existence of the two mouse lemur species. Sixty-five out of 379 identified daily sleeping sites were leaf nests. These represented a total of 35 different leaf nests, used by 15 out of 18 females. The relative leaf nest use differed between sites during five out of six months, but without a consistent pattern. Interspecific competition can therefore not explain leaf nest use. Leaf nest use differed seasonally and may be partly explained by thermoregulatory advantages in the site with lower minimum temperatures. Nest use was furthermore higher than expected in both sites during the rearing season that indicates the role of nests in infant protection. For the first time, we could confirm that golden-brown mouse lemurs build leaf nests themselves. Nest building lasted between 46 and 68 min, which shows that this task is time consuming and therefore probably costly.

Sleeping and Ranging Behavior of the Sambirano Mouse Lemur, Microcebus sambiranensis

“…The use of foliage nests may be due to restricted availability of suitable tree hole sleeping sites, as suggested for Microcebus ravelobensis (Radespiel et al 2003; Thoren et al 2010). The high usage frequency of foliage nests may also be due to competition for tree hole sleeping sites from larger sympatric nocturnal lemur species such as Lepilemur sahamalazensis and Mirza zaza , both of which are known to use tree holes as sleeping sites (Seiler et al 2013a).…”

The lack of female dominance in golden‐brown mouse lemurs suggests alternative routes in lemur social evolution

“…Those sleeping sites often possess lower quality (e.g., in dense vegetation, tangles of lianas, leaf nests or single leaves) than those of M. murinus and are changed on a regular basis . Moreover, female golden-brown mouse lemurs do not rear their infants in high quality tree holes, but continue to use self-constructed leaf nests or other structures and change them quite frequently (Thorén et al, 2010). The necessity to regularly and jointly squeeze into a small shelter may require females to exhibit more social tolerance toward males.…”

Resting and nesting in a small mammal: sleeping sites as a limiting resource for female grey mouse lemurs

“…We classified sleeping sites into the following three categories: (1) tree holes: this comprised cavities in tree trunks and branches; (2) (leaf) nests: spheres built from leaves incorporating supporting structures such as branches, abandoned birds' nests and plant creepers; and (3) open sites: usually located in branches and occasionally on the ground without any visual cover. Although we did not observe nest building, it has been described for golden-brown mouse lemurs, Microcebus ravelobensis (Thorén et al 2010). Thus, it is highly likely that females built leaf nests themselves, as nests were usually built from fresh leaves originating from tree species other than the one they were found in.…”