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Emily Sluzas: National Geographic Young Explorer and Lead PI
Erik R. Patel (PhD Candidate, Cornell University)
Dr. Abigail Derby (Stony Brook University)
Dr. Steig Johnson (Assistant Professor, University of Calgary)

Project Abstract

Marojejy National Park, a newly inaugurated World Heritage Site, is a high conservation priority since it is known to be one of the most biologically diverse regions in Madagascar due to its large elevational range.  This area also includes some of the few remaining large tracts of intact lowland rainforest. With 11 species of lemurs, including the critically endangered silky sifaka (Propithecus candidus), primate diversity is high as well. 

However, population densities were not yet available for any of Marojejy’s lemurs.  Three prior lemur surveys have been conducted, but only one within the last 10 years. Prior lemur surveys have been somewhat brief in duration and have been restricted to the eastern and western portions of Marojejy.  From June 7 to August 8 2007, we conducted the first lemur survey in the northern region of Marojejy.  Line-transect surveying was used along three transects:  Two low elevation transects, each 1500m, and one 2000m high elevation transect.  Sixty-three diurnal replicates were completed along each of the lower transects and 50 diurnal replicates were conducted along the upper transect.  Eleven nocturnal replicates were also conducted along each of the three transects.  Total survey effort was high:  344 kilometers of transects were walked.  Eight of Marojejy’s 11 lemur species were found during 140 encounters. Conservation priority taxa found included Propithecus candidus and Allocebus trichotis.  Other taxa seen were Avahi laniger, Eulemur albifrons, Eulemur rubiventer, Hapalemur grieus, Lepilemur mustilenus, and Microcebus rufus. Additional lemur surveys are planned to cover the remaining areas of Marojejy.

Erik Patel and Abigail Derby were invited by the mayor of Sambava and Alliance Francaise to give a televised presentation at city hall about silky sifaka conservation, behavioral biology, and this survey.  This presentation was broadcast on television several times in the north of Madagascar.  An article discussing their presentation also appeared in the capital, Antananarivo, in the newspaper Midi Madagascar.