Using reef balls to protect critical turtle habitat in Sarawak, Malaysia
Source/Photos: James Bali
Four species of sea turtles namely the leatherback (Demochelys coriacea), green
turtle (Chelonia mydas), hawksbill (Eretmochelys imbricata) and olive ridley
(Lepidochelys olivacea), nest along the sand beaches and islands of Sarawak. Green
turtles account for 99% of nesting sea turtle recorded yearly. The main sea turtle
nesting sites are located on the Sarawak Turtle Islands (Talang-Satang National
Park), consisting of Talang-Talang Besar, Talang-Talang Kechil and Satang Besar.
All species of Chelonidae and Dermochelyidae are listed as Totally Protected Animal,
under the Wild Life Protection Ordinance, 1998 (Amended 2003). Any person who
hunts, kills, captures, sells, offers for sell or claim to be offering for sale, imports,
exports, or is in possession of, any totally protected animal or any recognizable part
or derivative thereof, or any nest thereof, except in accordance with the permission writing of the Controller of Wildlife for scientific or educational purposes or for protection and conservation of such protected
animal, shall be guilty of an offence: Penalty – imprisonment for two years and a fine of twenty five thousand Ringgit (Sarawak
Government Gazzette, 2003).
In the old days the numbers of eggs harvested on the Sarawak Turtle Islands were astronomical: more than 3,000,000 were
collected in 1936 (Pritchard, 1979). At the present time, the Sarawak turtle population is in serious trouble, suffering from over
90% exploitation of the eggs laid since 1951. Besides over -exploitation of green turtles eggs in the past, accidental catches of
adult turtles in fishing gears are also a major contributor to declining of turtle population in Sarawak (Tisen and Bali, 2000).
Every year, significant numbers of adult turtles have been found dead and believed to be caught in trawler nets. Around 70 to adult turtles were found stranded in Sarawak’s beaches every year before 1998 (Bali et. al. 2004). The patrols against these illegal
trawlers are not effective because the trawlers can always spot the patrol boat first and flee immediately.
In view of this, the Sarawak Reef Balls Project was initiated. Reef balls were deployed randomly at areas that were identified as
inter -nesting swimming grounds for turtles during nesting season. With a sharp and rough surface, and weighing almost 2 tonnes,
reef balls are suitable for ripping the trawler nets that become entangled on them. The aim is to keep trawlers away from the sea
turtle internesting habitats.
Since 1998, 2584 units of reef balls were deployed by the Sarawak Reef Balls Working
Group (SRBWG) along the Sarawak coast (100 reef balls were sponsored by PETRONAS).
1572 reef balls were used for protection of sea turtles internesting areas around Talang-
Satang National Parks. Another 1012 units were deployed at Lawas, Bintulu and
Kampung Buntal (Kuching) in order to protect the fishing grounds of traditional
fishermen from the illegal trawlers.
Deployment of reef balls in areas identified as internesting swimming grounds for sea
turtles around Talang-Satang National Park resulted in a marked reduction in number of
dead turtles reported (around 20-30 dead turtles annually compared to 70 to 100 before.....
