NUMBER 6 OCTOBER 1986
NUMBER 6 OCTOBER 1986
During a visit to Sabah, Malaysia, from 28 June through 10 July 1986 I spoke to several
people familiar with wildlife conservation in Kota Kinabalu and Sandakan. Fishermen report
few, if any, sightings of dugongs, which are considered very rare, or possibly extirpated, along
the coast in Sabah. The last animal reported from the Sandakan area was butchered and eaten in
1984. I also spoke to a biologist studying proboscis monkeys in the mangrove forests of
Sarawak, Malaysia. Dugongs also are thought to be rare or extirpated in this region of
Borneo. Intense fishing and the introduction of nylon fishing nets probably are related to the
decline in dugong numbers in northern Borneo.
- Galen B. Rathbun (U.S. Fish & Wildlife Service)
Manatee Research at INPA. While Robin Best is working on his doctoral degree at
Cambridge, England, manatee research at the Instituto Nacional de Pesquisas da Amazo^nia
in Manaus continues under the interim supervision of Elton Pinto Colares. He reports on recent
activities as follows:
The objective of the aquatic mammal project at INPA is to study the distribution,
exploitation, and ecology of aquatic mammals in order to better understand their role in the
ecosystem and their importance to the human population along the rivers of Amazonia. The
project also seeks to study the basic biology, feeding habits, growth, behavior, etc., of aquatic
mammals, and on this basis to develop plans for their conservation and rational utilization
and techniques for raising them in captivity. To these ends we are carrying out the
following investigations on the Amazonian manatee: food preferences; feeding habits; annual
variation in aquatic macrophytes and their nutritional constituents; daily food consumption;
digestibility of food and passage time through the digestive tract; anatomy of the digestive tract
and sites of nutrient absorption; optimum composition of milk formula for development of
manatee calves; endocrinology; cytogenetics; and age determination.
New Manatee Legislation. Robin Best reports that, as a result of new legislation (Portaria
No. 011 of Feb. 21, 1986), the Brazilian federal fisheries agency SUDEPE now has authority
to protect manatees, small cetaceans, and seals. This should mean that wardens of either IBDF
NUMBER 6 OCTOBER 1986
(the federal forestry agency, which has traditionally had jurisdiction over manatees and most
other wildlife) or SUDEPE can now protect these animals. Robin had suggested and supported
this action, and Sirenews is glad to hear that it has been taken.
New West Indian Manatee Project. The Environmental Department of IBDF has
recently begun a project on the biology of Trichechus manatus in Brazil. This will center around
a radio-tracking study, and is based at a field station at Barra de Mamanguape in Paraiba.
The project is headed by Mo^nica Borobia, a former student of the manatee project in Manaus.
Because of the station's remoteness from libraries, she would like very much to receive reprints
on marine mammals. Her mailing address is: Mo^nica Borobia, a/c Dr. Henry Matthews,
ESAM, C.P. 137, Mossoro', RN 59.600, Brasil.
Can a Saw-fish (Pristis sp.) Kill a Dugong? On 15.4.86 a male dugong 2.73 m in length
was found floating near Manoli Island in the Gulf of Mannar. The animal was towed to the
shore and examined. There were many deep gashing wounds on the ventral side of the dugong.
Some of the wounds were as long as 50 cm and 2 cm deep. The flippers were perforated by the
injury. The animal had just died, as indicated by the fresh blood in the viscera. The local
fishermen say that saw-fish (Pristis sp.), which are common in the area, attack dugongs, and
similar cases have been seen by them. According to them the saw-fish, which lies buried in the
sand, gets provoked when the dugong goes near them browsing the sea-grass. The shadow of
the dugong provokes them to attack. The fishermen also seem to be cut by the Pristis sp. in
these areas. Dr. Francis Day (1878), the well-known author on Indian fishes, also has reported
such attacks on fishermen by the saw-fish. Further, two Echenies naucrates (sucker-fish) were
found attached near the armpit of the dugong.
I would appreciate knowing if any dugongs attacked by saw-fish have been reported by
earlier workers. Comments from sirenian workers on these observations are welcome. R. S.
Lal Mohan (Research Centre of CMFRI, West Hill, Calicut 673005, India)
DEVELOPMENT OF DUGONG TELEMETRY GEAR A PROGRESS REPORT
Several years ago Helene Marsh of James Cook University inquired if personnel of the U.
S. Fish and Wildlife Service's Sirenia Research Project could apply the radio-tracking
techniques used on manatees in Florida to dugongs in Australia. James Reid and I agreed to
develop the belt, tether and transmitter housing for dugongs, based on our experience with
manatees (Rathbun, G.B., J.P. Reid, and J.B. Bourassa. 1986. Design and construction of a
tethered, floating radio-tag assembly for manatees. Unpubl. MS., U.S. Fish & Wildlife Service,
Gainesville, Fla.). Using morphometrics and a cast of the peduncle and fluke region of a
NUMBER 6 OCTOBER 1986
dugong, a prototype peduncle belt was designed and built at the Service's Gainesville
Research Station in Florida. The VHF transmitter housing used on the manatees was used as a
model for an improved version for dugongs. The tether developed for manatees has remained
essentially unchanged. In order to test and further develop the new assembly Helene Marsh and
I applied for a Marine Technology and Science Grant from the Australian Government, which
was approved in late 1985.
The first step in developing the prototype harness was to test it on captive dugongs, which
are found only in Japan and Indonesia. The Japanese did not want their animals disturbed, but
the manager of the Javya Ancol Oceanarium in Jakarta, Mr. Tas'an, agreed to let us work with the
two dugongs under his care. With the help of Tas'an, a research proposal to test the attachment
on the dugongs in Jakarta was approved by the Indonesian Government in January 1986. Helene
Marsh, Anthony Preen from the Meteorology and Environmental Protection Administration of
Saudi Arabia, Andrew Smith, a postgraduate student of Marsh's, and I met at the Oceanarium in
Jakarta on 11 June 1986. The two captive dugongs were fitted with peduncle belts, tethers,
and dummy floating transmitter housings and these were monitored for 16 days, when they
were removed. During this time several modifications to the belts were made in order to reduce
the possibility of abrading the dugongs' skin.
Additional funding from UNEP has been promised, which will allow us to test the new
attachment on free-ranging dugongs. These tests are due to be completed in late 1986 in
northern Queensland. Galen B. Rathbun
HAVE YOU ANY EDUCATIONAL MATERIAL ON SIRENIANS?
It has been suggested that the IUCN Sirenia Action Plan, currently under review [?], be
expanded to include conservation [?] and education as well as research options. For this purpose
it would be useful to have a list of educational and public awareness material on sirenians
that is currently available in different languages and parts of the world. This would include
audiovisual materials (films, slides, records, etc.), posters, buttons, stickers, leaflets,
pamphlets, and teachers' guides, as well as popular and review articles. Please send to
Sirenews examples, copies, or a description (with prices, ordering information, and
conditions for reproduction or use where possible) of any such materials that are available in
your area. (Hopefully you are already making Sirenews aware of any published articles, popular
or technical, that come to your attention!) If the materials cannot be purchased, please let us
know of their existence all the same, they may provide examples for others to emulate. UNEP
is already preparing a catalogue of such items for marine mammals in general, but it would be
worthwhile to develop a more specialized one that could be appended to our Action Plan in
order to provide a basis for the development of more specifically appropriate materials for
NUMBER 6 OCTOBER 1986
SIRENIAN CROSSWORD PUZZLE
No newspaper is complete without one! Test your knowledge of sirenian trivia. Solution in the
next issue. (Sirenews thanks the Aquatic Weed Program, University of Florida, Gainesville, and
its computer for assembling these words into a puzzle for us.)
Judith Delaney, Wendy Hale, and Renee Stone, Manatees: An Educator's Guide to the
Natural History, Habitat, Problems, and Conservation of the Order Sirenia. 28-page booklet, 2
leaflets, and 17" x 22" poster. Florida Department of Natural Resources, Tallahassee.
(Available on request from the Florida Audubon Society, 1101 Audubon Way, Maitland, Fla.
The schoolteacher in search of material for a biology lesson, the student needing
information for a class project, the researcher besieged by schoolchildren's requests for
"everything you have on manatees" all can now relax; salvation has come. Florida's Save the
Manatee Committee, sponsored by the Florida Audubon Society, has produced an envelope
stuffed full of attractively presented, up-to-date information on manatees and their relatives,
designed for primary and secondary schools in Florida but marvellously useful wherever
teachers, students, and the general public want to know something about seacows. The heart
of the package is a booklet filled with information on manatee biology, manatee conservation
and regulatory laws in Florida, aquatic ecology, marine mammals in general, and sources of
further information. All this is interspersed with puzzles, suggested activities, and ideas for
helping manatee conservation efforts. Four pages are designed to be duplicated for individual
students; copy and distribution of all the material are encouraged. As the authors state, the
"activities can be adapted to suit the special needs, ages, and abilities of your students and are
designed for multidisciplinary study areas."
"While this guide focuses on the West Indian manatee, the importance of interdependencies
within the whole ecosystem and the role the manatee plays" are stressed throughout. However,
a lot more stress could have been placed on human population growth in Florida as the root cause
of the manatee's problems. This is touched on in the suggested activities on pages 19 and 20,
which are good as far as they go; but please let's take off the kid gloves and put the finger on
the real issue, even if it is unpopular in certain circles. Why not a graph of Florida's human
population growth, for comparison with the graph of manatee mortality? Why not some
discussion questions explicitly challenging the belief that increase in our population is a good
thing? Come on, teachers, the kids aren't going to get the message if you don't have the
courage to tell them!
NUMBER 6 OCTOBER 1986
The booklet is supplemented by a pair of leaflets comprising a concise "manatee fact sheet"
of basic natural history data; a list of resource agencies and organizations in Florida concerned
with manatees; and two solid pages of references to recent popular and semipopular articles
on sirenians, reference books, "books especially for young readers", and available audiovisual
aids. Also included is an attractive four-color wall poster by Mary Ruth Sprankel portraying the
"Sirenians of the World", with a map of their distribution. The manatee and dugong pictures are
quite true-to-life (something never to be taken for granted), and even the one of Steller's sea cow
is better than most you will see in the literature.
Throughout, editorial and typographical errors are few, and the facts are accurate. And there's
more: "Also available as part of the overall package is a 23 minute video tape program, 'Silent
Sirens: Manatees in Peril,' available in either 1/2" or 3/4" format from your district media
centers. Written permission must be obtained from the Florida Audubon Society before
duplicating this video cassette in part or in its entirety."
I am impressed. Together with the authors, I hope "that the use of this guide will result in
informed decisions, responsible behavior, and constructive actions towards the protection of the
manatee and its habitat in Florida." It should also serve as a model to be emulated by public
awareness programs in other countries. If it doesn't, it won't be the fault of those who created
this excellent and unique resource. DPD
Mary Unterbrink, Manatees: Gentle Giants in Peril. St. Petersburg (Fla.), Great Outdoors Publ.
Co., 1984: 1-47. Illus. (Softbound; ISBN 0-8200-9914-7. Order from Great Outdoors
Publishing Co., 4747 28th St. North, St. Petersburg, Fla. 33714 USA. Price US$2.95 +
$1.00 postage & handling [$2.00 for orders over $10.00]; Florida residents add 5% sales tax.)
This little book gives a thorough and readable introduction to the problems faced by the
manatee in Florida. Suitable for students in grade school or above, or anyone interested in
manatees, it covers the last two decades of research and conservation efforts in an
anecdotal style, well seasoned with up-to-date facts on the manatee's life history. Several
active manatee researchers contributed information and helped ensure the book's accuracy. The
illustrative sketches of manatees by Robert G. Cannon are reasonably true to life, though the
drawing of a dugong reflects the fact that most wildlife artists still have little grasp of sirenian
anatomy, especially facial anatomy.
Emphasis is properly placed on the various threats posed by man's activities, and the book
gives the Manatee Hotline telephone number and the locations of the various manatee
sanctuaries in Florida. But it could usefully have included more explicit instructions on what
boaters, divers, and would-be manatee watchers should and should not do, in accordance
with present knowledge and applicable laws. For example, the various degrees of limitation
on boat speeds in and near manatee sanctuaries should have been described, and the
restrictions on contact of manatees by divers should have been more clearly explained.
NUMBER 6 OCTOBER 1986
Readers would also have welcomed advice on when and where to see wild manatees without
disturbing them. It is important for the public to have some background knowledge of what
manatees are and how they live, but it is equally important to give them detailed guidance on
minimizing the problems we humans create.
The ultimate and most insidious source of these problems is human population growth, yet
nowhere does the author hint that Florida's explosive growth in people, boats, marinas, and
general busyness is the real issue. The lesson to be driven home is that most wildlife
management is really people management. Despite the book's stress on the manatee's present
peril, that lesson could have been made still clearer, and this book accurately reflects how far
public comprehension of it has yet to go.
Although this booklet does not completely meet the need for a reliable popular work on
manatees, it makes a worthwhile contribution, and I hope it will be used by schools and
conservation groups as the convenient resource that it is. An improved and expanded edition
would go even further toward filling the need, and growing market, for nontechnical sirenian
_Lung Structure and Mechanics of the West Indian Manatee (Trichechus manatus) (Michael
R. Bergey). Marine mammals are capable of exchanging lung air very rapidly compared
with similarly sized terrestrial mammals. This capability has been attributed to the great
stiffness of marine mammal airway walls, which reduces flow-induced restriction of the lumen
during rapid exhalations. In this study, manatee lung morphology and flow mechanics were
investigated using specimens harvested from dead, stranded animals. Airway dimensions were
measured from vinyl acetate lung casts, direct dissection, and histological sections. Static
volume-pressure relationships were recorded by measuring lung volume changes while pressure
on the lung surface was varied to simulate chest wall movements. Maximum expiratory flow-
volume data were obtained by venting inflated lungs rapidly into an evacuated chamber
while recording instantaneous lung volume changes.
Manatee lung airways differed greatly from the terrestrial pattern by possessing cartilage
plaques at the level of the respiratory bronchioles, and unbroken rings within the walls of all
larger airways. The excised lungs changed volume greatly with small changes in inflation
pressure, and demonstrated very small residual volumes when inflation pressure was reduced
to zero. Maximum expiratory flow rates for manatees followed the pattern of other marine
mammals, in which flow rates at all lung volumes exceeded predictions based on terrestrial
mammals. This is consistent with the observed high degree of airway reinforcement in
manatee lung airways, which may stabilize airway wall dimensions, preventing flow-
induced restriction. [Abstract of a master's thesis in Biological Oceanography submitted to
the University of Miami, Florida, in June 1986 and supervised by D.K. Odell.]
NUMBER 6 OCTOBER 1986
Anderson, P.K. 1986. Dugongs of Shark Bay, Australia -- seasonal migration, water
temperature, and forage. Natl. Geographic Research .... [Autumn 1986]
Bayliss, P. 1986. Factors affecting aerial surveys of marine fauna, and their relationship to
a census of dugongs in the coastal waters of the Northern Territory [Australia]. Aust.
Wildl. Res. 13(1): 27-38.
Caldwell, D.K., and M.C. Caldwell. 1985. Manatees Trichechus manatus, Trichechus
senegalensis, and Trichechus inunguis. In: S.H. Ridgway and R.J. Harrison, eds., Handbook
of Marine Mammals. Vol. 3: The Sirenians and Baleen Whales. Academic Press, London:
Domning, D.P., and L.C. Hayek. 1986. Interspecific and intraspecific morphological
variation in manatees (Sirenia: Trichechus). Marine Mammal Science 2(2): 87-144.
Domning, D.P., C.E. Ray, and M.C. McKenna. 1986. Two new Oligocene
desmostylians and a discussion of tethytherian systematics. Smithsonian Contrib.
Paleobiol. 59: iii + 56.
Frailey, C.D. 1986. Late Miocene and Holocene mammals, exclusive of the Notoungulata,
of the Rio Acre region, western Amazonia [Brazil]. Nat. Hist. Mus. Los Angeles
County Contrib. Sci. No. 374: 1-46. [Fossil Trichechidae]
Gallivan, G.J., J.W. Kanwisher, and R.C. Best. 1986. Heart rates and gas exchange in the
Amazonian manatee (Trichechus inunguis) in relation to diving. J. Comp. Physiol. B.
Biochem. Syst. Environ. Physiol. 156(3): 415-424.
Halstead, L.B. 1985. On the posture of desmostylians: a discussion oflnuzuka's
"herpetiform mammals". Mem. Fac. Sci. Kyoto Univ., Ser. Biol. 10(2): 137-144.
Hanitsch, R. 1908. Guide to the Zoological Collections of the Raffles Museum, Singapore.
Singapore, Straits Times Press, Ltd.: 112 pp. [P. 13 mentions a captive dugong exhibited
at the Museum for a few weeks in 1895. Bob Brownell thinks this was the earliest
instance of a dugong being kept in captivity. Can anybody beat that record?]
Hudson, B.E.T. 1986. Dugongs and People. Oceanus 29(2): 100-106.
NUMBER 6 OCTOBER 1986
Inuzuka, N. 1985. Are "herpetiform mammals" really impossible? A reply to Halstead's
discussion. Mem. Fac. Sci. Kyoto Univ., Ser. Biol. 10(2): 145-150.
Kamiya, T., P. Pirlot, and Y. Hasegawa. 1985. Comparative brain morphology of miocene
and recent sirenians. Fortschritte der Zool. 30: 541-544. [Comparison of a brain of Dugong
with endocasts of the desmostylian Paleoparadoxia.l
Marsh, H. 1986. 'Dugong is Number One Tucker.' Oceanus 29(2): 102.
Nishiwaki, M., and H. Marsh. 1985. Dugong, Dugong dugon (Mu"ller, 1776). In: S.H.
Ridgway and R.J. Harrison, eds., Handbook of Marine Mammals. Vol. 3: The Sirenians and
Baleen Whales. Academic Press, London: 1-31.
Ono, K., and T. Uyeno. 1985. Tertiary vertebrates from Sado Island, Niigata Prefecture,
central Japan. Mem. Natl. Sci. Mus. (Tokyo) No. 18: 65-72. [In Japanese; English
Pervaiz, S., and K. Brew. 1986. Purification and characterization of the major whey proteins
from the milks of the bottlenose dolphin (Tursiops truncatus), and Florida manatee
(Trichechus manatus latirostris) and the beagle (Canis familiaris). Arch. Biochem.
Biophys. 246(2): 846-854.
Pervesler, P., and F. Steininger. 1986. Die Seekuh Metaxytherium krahuletzi: Skelett
eines 22 Millionen Jahre alten Meeressa"ugetieres aus Ku"hnring. Katalogreihe des
Krahuletz- Museums [Eggenburg, Austria] Nr. 7: 12 pp. [Museum pamphlet on the
excavation and exhibition of an Early Miocene sirenian skeleton.]
Rathbun, G.B., and P.B. Best. 1986. [Review of] S.H. Ridgway and R.J. Harrison, eds.,
Handbook of Marine Mammals. Vol. 3: The Sirenians and Baleen Whales. Mar. Mamm. Sci.
2(3): 236-239. [Rathbun reviews Nishiwaki & Marsh, 1985, and Caldwell & Caldwell,
1985, cited above.]
Rowlatt, U., and H. Marsh. 1985. The heart of the dugong (Dugong dugon) and the West
Indian manatee (Trichechus manatus) (Sirenia). J. Morphol. 186(1): 95-106.
Shoshani, J. 1986. Mammalian phylogeny: comparison of morphological and
molecular results. Molec. Biol. & Evol. 3(3): 222-242. [Relationships of Sirenia and
Desmostylia within "Paenungulata".]
NUMBER 6 OCTOBER 1986
Takahashi, S., D. Domning, and T. Saito. 1986. Dusisiren dewana, n. sp. (Mammalia:
Sirenia), a new ancestor of Steller's sea cow from the Upper Miocene of Yamagata
Prefecture, northeastern Japan. Trans. Proc. Palaeont. Soc. Japan, N.S., No. 141: 296-321.
CHANGES OF ADDRESS
Dr. K. Radway Allen, 20/8 Waratah Street, Cronulla, N.S.W. 2230, Australia
Barbara J. Bernier, Miami Seaquarium, 4400 Rickenbacker Cswy., Key Biscayne, Fla. 33149
Dr. R. S. Lal Mohan, Research Centre of CMFRI, West Hill, Calicut 673005, India
Dr. Thomas E. Lovejoy, World Wildlife Fund, 1255 23rd St. NW, Washington, D.C. 20037
A NOTE TO OUR READERS
Please notify us if your address changes or if the address we are using is incorrect. If you
no longer wish to receive Sirenews, please send us a postcard to let us know so that we can save
on costs of printing and mailing. On the other hand, if you find Sirenews useful in your work,
we'd also like to hear from you in the form of reports of your sirenian-related activities, and
copies of any publications on sirenians (popular or technical) that you produce. Several of
you are listed in our file as heads of sirenian research projects in your respective countries,
but in many cases we have received no news of your projects, whether they are enjoying
success or otherwise. The purpose of Sirenews is to foster communication among sirenian
workers everywhere, and just as you have benefitted from hearing news of other projects in
these pages, others will benefit from hearing about what you are doing. So please write!
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