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Sumatran Rhino Sumatran Rhino
Scientific paper (copy and paste in browser)
http://scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=ARLOFJ000004000003000083000001&idtype=cvips
The "Singing" Sumatran Rhino
Within the last ten years the Sumatran rhino (Didermoceros sumatrensis)
population has dropped 50%, and only 200 to 300 individuals exist. Due to
habitat loss and poaching, the Sumatran is critically endangered. There are only
four Sumatran rhinos in captivity, three at the Cincinnati Zoo, named Andalas,
Emi and Ipuh and one at the Bronx Zoo named Rapunzel. Sumatran rhinos are
solitary, although males and females are seen together during courtship. Their
native habitat is dense tropical forest and mountain moss forest, and they are
extremely dexterous, being able to climb "almost sheer cliffs." Sumatrans are
reclusive and tracking them in dense forest has proven difficult, so little is
known about their behavior. They are the smallest living rhino, standing 3-5
feet (0.9 - 1.5 meters) tall. The Sumatran rhino is the oldest living species of
rhino, and is a descendant of the wooly rhinoceros. It is thought that they have
remained unchanged for the last 2 million years. Sumatrans are covered in long
course, reddish-brown hair, with tufts on their ears.
The Sumatran's communication is very unlike that of other rhino species. White
rhinos communicate rarely, and blacks and Indians have interesting "moos" and
"trills." However, none of these species produce vocalizations constantly, nor
are they songlike as the Sumatran's are. There has never before been a
scientific study performed on Sumatran vocalizations, in fact, few persons have
ever even heard these creatures. Because the outside enclosures at both the
Cincinnati zoo and the Bronx zoo are set back from the public walkways, and
Sumatrans are basically "shy", few individuals except the keepers and those that
work closely with them, have ever heard the Sumatran's beautiful "songs."
In novel research performed by Fauna Communications, three adult Sumatran
rhinos, housed at the Cincinnati Zoo, were recorded from 1 - 3 meters. Two
Statham Radio microphones and two TCD-D8 Sony DAT recorders recorded from 9 Hz
to 20 kHz. Analysis, including power spectrum, spectrographs and filtering were
performed using National Instrument's Polynesia. The rhinos proved to be
extremely vocal and produced signals almost continually. The rhinos would even
produce vocalizations when they were eating. Distinct calls, including several
types of "eeps," 70 Hz - 4000 Hz (57-92 dB); "whales," 100 Hz - 3200 Hz (87 dB);
and "whistleblows", 17 Hz - 8000 Hz (100 dB) were discovered. The "whistleblow"
has high dB infrasound that would be advantageous for use in the rhino's forest
habitat.
After recording and analysis, since some of the vocalizations sounded so similar
to whales, a scientific recording of Humpback whale song was procured and
analyzed. It became clear immediately that some Sumatran rhino vocalizations
sound similar to, and resemble (under analysis) some humpback whale signals.
Fauna Communications contacted several paleontologists, one whom stated that the
similar songs (rhino and whale) could be convergent evolution, or be what is
known as an ancestral song. Sumatrans are perissodactyls, odd-toed ungulates.
There is some research that indicates that rhinos may be a sister group to
whales.
After the conclusion of this study Emi from the Cincinnati zoo gave birth to a
male, named Andalas. This is the first Sumatran rhino to be born in captivity
for 100 years. Because of the critically endangered status of the Sumatran, it
may be that protected environments will the only places that can keep this
remarkable animal from becoming extinct.
"Can you speak rhinoceros? Of courseros, can't you?"
Dr. Dolittle
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