Class: Mammalia
Sub-class: Eutheria
Order: Sirenia
Family: dugongidae
Species: Dugong dugong (MÜller)
Local name: Galed, Arowsa al Baher
Adult dugong grow to more than three meter in length and up to 4420
kg, and have a rotund body with horizontal tail and forward pectoral
fins. Dugong eyes are set laterally and cover a broad filed of. The
auditory opening is small and set laterally behind the eyes; however
hearing is reported to be acute.
2- Overview
Dugong( Dugong dugong ) is a large herbivorous marine mammal and is
the only living member of the family Dugongidae .The distribution
and abundance of dugong in Egyptian waters of the Red Sea had not
been assessed in detail.(Gohar 1957 ) obtained specimens from near
Hurghada and Ras Banas , Rigl &Luke (1997) noted that Dugong were
regularly sighted in water south of Ras banas , and that small
numbers persisted further north at Safaga Bay ,Umm Redj ( near
Sheikh Malek ) and Marsa Embark. Marsh et al. (2002) reported
sightings of dugong off the Sinai Peninsula, Tiran Island and Quseir
Port .The Egyptian Environmental affairs Agency (EEAA) commenced a
study in 2001 to identify the spatial distribution of dugongs in
Egypt's red Sea, particularly in relation to marine protected area
(MPA), quantify the relative abundance of dugong through time,
identify important habitat for this species and rank sources of
dugong mortality in order to target management.
3- Conservation Status
Dugong is listed as vulnerable to extinction in the International
union for the Conservation of Nature and Natural Resources Red Data
Book of Threatened Species (IUCN 2000), The dugong is listed on
Appendix 1 of the Convention on International Trade in Endangered
Species of wild Fauna and Flora (CITES) .In Egypt, The dugong is
protected under the Wildlife Conservation Act 1950.
4- Life history and reproductive ecology
Dugong is long lived animals with a low reproductive rate, long
generation time and high investment in each offspring. Age has been
estimated by counting seasonally deposited growth layers in the
tusks by Marsh et al 1984 , Longevity is approximately seventy years
and dugong over 2.5 meters are mature while male and female less
than 2.2 meters are probably immature . The pre –reproductive
interval is at least nine years and some times as long as seventeen
years. The female usually bear a single calf every 3 to 5 years, the
gestation period is about 13 months and the calf suckles for at
least 18 months.
5- Diet &Habitat
Dugong feed on sea grasses found in the shallow tidal and sub tidal
coastal water, Dugong feeding trails were observed in many sites as
Wadi El Gemal Hamata protected Area, Marsa Abu Dabab and Maras Egla.
Feeding trails ranged from 10 to 20 cm in width and up to 5 m in
length. Dugong preferred Halophila and Halodual species of sea
grasses.
6- Distribution and abundance
Few number of adult and juvenile Dugong reported from 2001 to 2003
at 13 sites situated between Hurghada and El shalatin. These sites
are : Wadi El Gemal , Sharm El Bahari , Safaga Island , gamoual
Keiper , El Shalatin , Sheikh malek , Wadi Gasos , Sheikh Saleim ,
El Quewah , Quseir port,Marsa Abu Dabab , Marsa Egla and Milia
Phroan in Hurghada . The minimum and maximum numbers reported were
12 each in 2001 and 2003, and 17 in 2002. We do not know if some
individuals were observed at different sites in the same years or
not.
Questionnaire Program for collecting data for Dugong in the Egyptian
Red Sea Coast was operating be RSMP is still working, any
information available will be great in assist the Dugong status.
For more information, please contact Biology , Mohamed A. Ghany
Tel and Fax +20-65-3447719/24/25/26
emailmabdelghany@hotmail.com
Editor : By Ayman Afifi
MSc, Oceanography, CM, F1, USA:
National parks Of The Red Sea
