Range and conservation updates for the Critically Endangered blue-eyed black lemurEulemur flavifronsand the Vulnerable black lemurEulemur macaco

Abstract

The Critically Endangered blue-eyed black lemurEulemur flavifronsof north-western Madagascar is one of the most threatened primates. The majority of research and conservation efforts for the species have been restricted to the Sahamalaza Peninsula but there are unstudied and unprotected populations farther inland. The dearth of information regarding the transition betweenE. flavifronsand its parapatric sister species, the Vulnerable black lemurEulemur macaco, and the possibility of a hybrid population complicates conservation planning for both species. We surveyed 29 forest fragments across both species’ ranges to investigate the boundary between the taxa, whether hybrids persist, and the threats to lemurs in the region. We foundE. flavifronsin six fragments andE. macacoin 17. We never observedE. flavifronsandE. macacoin the same location and we found no conclusive evidence of hybrids. Three fragments in whichE. flavifronswas present were north of the Andranomalaza River, which had previously been considered the barrier between the two species. Based on these observations and a literature review, we provide updated ranges, increasing the extent of occurrence (EOO) ofE. flavifronsby 28.7% and reducing the EOO ofE. macacoby 44.5%. We also evaluate the capacity of protected areas to conserve these lemurs. We recommend additional surveys and the implementation of an education programme in this region to help conserve both species.

Do functional traits offset the effects of fragmentation? The case of large‐bodied diurnal lemur species

“…We obtained occurrence points for all diurnal and cathemeral lemur species, totaling 32 taxa, from the data set collated by Tinsman (2019). These include the genera Eulemur (12 species), L. catta , Hapalemur (four species), Prolemur simus , and Varecia (two species/three subspecies) from the family Lemuridae, and Propithecus (nine species) and Indri indri from the family Indriidae.…”

A Pervasive History of Gene Flow in Madagascar’s True Lemurs (Genus Eulemur)

“…For several reasons, the true lemurs of Madagascar (genus Eulemur , 12 species) form an excellent primate system that can be used to study the interplay between species limits and gene flow: (a) Eulemur experienced recent, rapid radiation, with a known history of hybridization [ 37 , 38 ]; (b) excellent resources are available for their genetics, geographic range, diet, and social behavior [ 39 , 40 , 41 , 42 ]; (c) the study of their biodiversity is important in light of urgent conservation concerns [ 43 , 44 ]. For many years, Eulemur was assumed to be a species-limited clade and was dismissed by many as Madagascar’s “little brown lemurs” (a nod to “little brown birds” à la ornithology) [ 45 , 46 ].…”

Habitat use by the island lemurs of Nosy Be, Madagascar

“…They are some of Nosy Be's most important pollinators and seed dispersers (C. R. Birkinshaw, 1999; C. R. Birkinshaw & Colquhoun, 1998). Black lemurs are threatened by habitat loss and degradation throughout their range (Tinsman et al, 2020). They may be able to compensate for lower quality forest by expanding their home ranges like the blue‐eyed black lemur ( Eulemur flavifrons ) does (N. Schwitzer et al, 2007), but we do not currently know how long black lemurs can persist in degraded forest.…”

“…Lokobe NP likely houses the largest remaining populations of both Claire's mouse lemur and the Nosy Be sportive lemur-the Nosy Be sportive lemur is endemic to Nosy Be, and Claire's mouse lemur is a near endemic, with limited reports of individuals on the mainland (Randriatahina & Volampeno, 2013;Sgarlata et al, 2019). The black lemur occurs on Nosy Be and the nearby mainland (Tinsman et al, 2020). However, the Nosy Be population may be genetically distinct from the mainland population (Rabarivola et al, 1996(Rabarivola et al, , 1998.…”