Lemurs are the most threatened mammals in the world: IUCN Red-List Workshop 2012

July 18, 2012 — Last week, 60 of Madagascar’s leading lemur conservationists and researchers gathered in Antananarivo (the capital) to reevaluate the IUCN Red-List conservation statuses of each lemur species.  It had been seven years since the last assessment.  New discoveries and increasing conservation threats since the coup d’etat in 2009 and ongoing political crisis warranted this reassessment.  The conclusion was that twenty-three lemurs qualify as Critically Endangered (up from 8), fifty-two are Endangered (up from 18), and nineteen Vulnerable (up from 14) to extinction.  “That means that 91% of all lemurs are assessed as being in one of the Red List threatened categories, which is far and away the largest proportion of any group of mammals,” said Dr. Russ Mittermeier, Chairman of the Madagascar Primate Specialist Group and President of Conservation International.  Unprecedented high levels of lemur hunting as well as escalating habitat disturbance are the main contributing factors.

I think many of us who participated as members of the Madagascar Primate Specialist Group in the week-long workshop felt a mixture of urgency, anger, and sadness, although there were a few glimmers of hope.  Among the topics of discussion, consensus was reached that the northern sportive lemur (Lepilemur septentrionalis), with only 17 remaining individuals, is the rarest lemur.  Numerous “data deficient” species were assigned Red-List categories in light of new data.  For example, enough had been learned in recent years about the extremely restricted ranges of Sahamalaza sportive lemur (Lepilemur sahamalazensis) and Sibree’s dwarf lemur (Cheirogaleus sibreei) to consider them “critically endangered” species.  Several AZE (Alliance for Zero Extinction) sites were identified, which are regions that are the last remaining refuge of critically endangered or endangered species.  For example, Lac Alaotra, Madagascar’s largest lake, is the only home for the Alaotran Bamboo Lemur (Hapalemur alaotrensis) whose population numbers are reportedly down to possibly a few hundred total remaining individuals!

It’s not all bad news though, several new populations of Greater Bamboo Lemurs (Prolemur simus) have been found in the past few years.  Its population numbers were believed to be less than 100 total individuals just a few years ago, but now more than 500 individuals are known to exist in the wild.  For many other species, such as the silky sifaka (Propithecus candidus) which I study, further surveys are needed to improve our estimates of global population size and geographic range.  As much as 30% of the silky sifaka population could be in Anjanaharibe-Sud Special Reserve, but there has not been a lemur survey there since 1994.  This past June, that reserve was actually closed to tourism for several weeks because of an outbreak of illegal mining…..another form of disturbance which has been on the rise in recent years.  It’s certainly not too late for lemurs in the wild, but new action and new strategies are needed.

-Dr. Erik Patel

Duke Lemur Center

SAVA Conservation Project Director