Smithsonian interviews Dr. Dittus

JUNE 30, 2016

For nearly 50 years, Smithsonian Conservation Biology Institute primatologist Wolfgang Dittus has studied and lived among the toque macaques in Sri Lanka. In our Q & A, he reveals how family relationships, intelligent behavioral strategies and a healthy environment are key to this species’ survival.

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For more than 48 years, I have been researching toque macaques at our study site in Polonnaruwa, Sri Lanka. Over the years, we’ve studied more than 4,000 macaques. We want to identify key behaviors and measure how they contribute to macaques’ ability to survive and reproduce in a changing environment. One important method we use to keep track of who is who, is making ID cards for individual macaques that include their identifying characteristics.

One of my goals as a scientist is to teach people how wonderful these monkeys are. People will only be willing to help conserve species that they love. They will only love these species if they understand them, and they will only understand these species if scientists (myself included) are telling the animals’ stories.

Juvenile toque macaques are very inquisitive and much more likely to take risks than the adults. I was just standing and observing them when one juvenile approached and touched me! When I first started the study, it took me a long time to habituate these monkeys to me being there. Once they’re used to a person, they don’t run away, but they don’t necessarily approach, either. […]

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The role of primates in conserving Sri Lankan biodiversity

March 2016: Dr. Dittus responds to questions from the Sri Lanka Secretariat of Biodiversity

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The importance of acknowledging the diversity of mammal subspecies

Jan 2014: Ceylon Journal of Science (Bio). Subspecies of mammals are critical to estimates of Sri Lankan biodiversity, set Sri Lanka apart from the Western Ghats as a global biodiversity hotspot and invites revision of current harmful conservation management practices.

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A pinch of skin to estimate body fat in monkeys

April 2015. The precision in growth and allometric development makes it possible to accurately estimate the mass of body fat in different regions of the body given the known relationship between skinfold thickness and mass of dissected adipose tissue.

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Macaque seeks refuge in U. S. embassy

January 2013. Conflicting press reports about macaque breaching  embassy security
A macaque had found its way into the U. S. embassy compound in Colombo on 20 December, 2012, and caught the attention of the leading newspaper in the American capital, the Washington Post, which ran three different articles on the event.  Sri Lankan newspapers, The Sunday Times and The Island, too, picked up the story.  All papers agree that a macaque monkey was found inside the embassy compound without triggering any security alarms.  Embassy staffers secured their offices from the intruder and alerted their own marine guards as well as the Department of Wildlife Conservation (DWC).  According to the Post, the U. S. marines chased the monkey into the adjoining compound – the British High Commission, but the Sri Lankan papers credited the DWC with restraining the panicked marines, capturing the tranquilized monkey and setting it free in the wild.
While newspaper reports appear to be serving different political needs, I herewith offer my own point of view.  Despite the fact that toque macaques are an endemic species, the Sri Lankan government had recently declared the species as a pest and, at the cost of millions of rupees, had distributed guns to the public to shoot macaques (a fact). Toque macaques are being persecuted in a most shoddy manner in this Buddhist country!  I suggest that this intrusive monkey most likely was an escaped or evicted pet from a Colombo residence where it had learned about its intended genocidal fate and sought asylum in the U. S. embassy.  Having been denied refuge by the Americans, it tried its luck with the Brits.
Wolfgang Dittus, PhD

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Nature Education for Teachers

28 August 2012. ACPD staff instruct teachers on nature and conservation
Staff of the Smithsonian Primate Research Station conducted a wildlife conservation and nature education program for 25 school teachers from the Polonnaruwa education zone. Provincial Director for science education,  Mr.SM Saluwadane, Zonal Director for science education,and Master in charge of the nature center at the Royal college Polonnaruwa participated for the program.  This session represented an expansion of ACPD staff teaching of students, to include a new phase involving teacher training in the Polonnaruwa District.

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VIDEO: rescue of rejected pet monkey

4 May 2012. Saving a destitute baby monkey can indirectly help conserve primates
Sunil Gunathilake, Research Co-ordinator on our team, rescues an infant toque macaque that had been raised as a pet and then abandoned on the streets of Polonnaruwa. Local town people alerted us and handed it over to Sunil.  The orphan was taken to our hospital and care facility at our research station. The BBC Planet Earth Live film crew assisted and recorded the event.
Read the full story feature article on BBC Nature and see a video of the rescue mission
Saving an orphaned or injured monkey does little to contribute that individual’s genes to future generations of its species; but it can help people to know monkeys better, maybe even to love them, and to galvinize them to conservation action.  And the other truth illustrated again here is that taking monkeys from the wild as pets is cruel to monkeys. Monkeys are highly intelligent and social primates which do best with their own kind.

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The BBC is here: “Gremlin” a rising star!

See video: cheeky monkey filming cameraman

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The Sunday Times newspaper of Sri Lanka (26 December 2010) published a solicited commentary by Dr. Wolfgang Dittus of how best to prevent macaque monkeys harassing tourists at the Dambulla temple.

He suggested an educational program whereby vendors and visitors are prevented from carrying food to the site.

For details see

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Science Conference

8 Jan 11. At the IFS Annual Review 2010, held in Kandy, Dr. Dittus presented recent research results from the Primate Biology Program.

The talk focused on the genetic, demographic and behavioral relationships involved in the avoidance of inbreeding in primates. The data spanned some 35 years of field observation and involved the genetic typing of about 1500 toque macaques.  Using 1113 genetically profiled pedigrees we noted that only about 1% of this wild population of macaques was truly inbred (at Coefficient of Inbreeding, F > 0.125). Most inbreeding was prevented by the dispersal of males from their natal group at puberty.  In addition, however, where close kin had an opportunity to inbreed, matings were prevented between close maternal relatives (parent-offspring, siblings, aunts, nieces) but not among maternal cousins, or, albeit rare, paternal relations. Although macaques recognize one another as individuals, the avoidance in inbreeding involves as yet little understood mechanism by which monkeys distinguish between close and distant relatives. The results have broad relevance among mammals including man.

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