@phdthesis{,

title = {The conservation biology of the dugong (Dugong dugon) and its seagrass habitat in Sabah, Malaysia, a basis for conservation planning},

author = {Rajamani, L.},

year  = {2010},

date = {2010-01-01},

journal = {Borneo Marine Research Institute},

number = {441},

pages = {315},

publisher = {Universiti Malaysia Sabah},

abstract = {Prior to 1999, dugongs were rarely observed in Malaysia. This first comprehensive

study of dugongs and their related seagrass habitats in Sabah, investigated the local

stakeholder environment, the abundance and distribution of dugongs, identified and

monitored threats to dugongs, and mapped seagrass habitats relevant to dugongs.

The study was conducted in two spatial scales namely, 1) Regional (to determine

dugong distribution in Sabah) (excluding Tawau) 2) Local - to determine local dugong

abundance, conduct seagrass mapping and community surveys at two study sites

Banggi island and Mantanani island. Community surveys consisted of a census,

interview surveys, a dugong monitoring programme and participant observation. This

information was used to determine stakeholder characters, and their perceptions of

the researcher, research project, dugongs and seagrasses. Local ecological knowledge

(LEK) of dugongs and seagrasses was also sought. The abundance, composition and

habitat area of seagrass was assessed using a method of visually estimating aboveground

seagrass biomass at sites along one kilometre transects perpendicular to the

coast. Biomass was estimated every 50 metres in shallow areas (up to 5 metres

depth) and every 100 metres in deep areas (greater than 5 metres depth). These sites

later form the basis of seagrass meadows using GIS applications. Standardised aerial

surveys were conducted regionally for the coastal waters of Sabah to determine

dugong distribution patterns. The communities of Banggi and Mantanani are

economically disadvantaged, practise destructive fishing and have little understanding

of ecological processes and concepts of conservation. However, the reasons for

dugong decline are known. Appreciation of the aesthetic value of dugongs within the

communities is varied. However, the community appears to have adequate local

knowledge of the dugong having cultural linkages through a dugong myth.

Approximately, 70% of the total population is young below the age of 30, who could

be receptive to new ideas. Outside influences from the media is widely available to the

community. The community is able to develop a relationship with the researcher and

participate cordially in research activities. Dugong numbers are very low in Sabah.

Fifty two dugongs were sighted in Sabah excluding Tawau. Based on these results,

crude estimates of minimal count are between 688 and 1376 dugongs residing in

coastal Sabah. Key dugong areas were identified to be Brunei Bay, Labuan Island, and

Sandakan Bay. Banggi Island and Mantanani Island supports a small population of

dugongs respectively. Based on this study, dugongs were subject to threats, which

were mostly anthropogenic. They were 1) blast fishing, 2) incidental entangling in nets

and 3) unsupervised tourism and vessel strikes. The number of mortalities in Sabah

(especially in Banggi Island), are high compared to dugong abundance results

obtained in this study. When Potential Biological Removal (PBR) estimates were

compared to crude estimates of yearly mortality, it is confirmed that dugong

populations are declining. Ten species of seagrass from two families were found in

Banggi Island and Mantanani Island. These include Halophila ovalis, Halodule uninervis

(broad and thin variety), Thalassia hemprichii, Cymodocea rotundata, Halophila

decipiens, Halophila spinulosa, Cymodocea serrulata, Syringodium isoetifolium, and

Enhalus acoroides. A new unidentified species of Halophila was collected in

Molleangan Island, west of Banggi Island. Approximately, 415 ha and 112 ha of

seagrass meadows were mapped in Banggi island and Mantanani island respectively

giving a total of 527 ha of seagrass available for dugong consumption. The



information obtained on the local communities, seagrass and dugong provided the

basis to inform a comprehensive conservation plan in Sabah. Key conservation

strategies include a dialogue and community education programme, provision of

alternative livelihoods, improving enforcement to prevent illegal fishing methods, comanagement

of dugong and seagrass resources, stringent controls on ecotourism and

vessel strikes, zoning of seagrass in marine protected areas and further research. As

the dugong is a migratory species, conservation management at an international level

with the neighbouring state of Sarawak, and countries of Brunei, the Philippines and

Indonesia is necessary.},

keywords = {conservation, dugong, GIS, habitat, Malaysia, Sabah, Seagrass},

pubstate = {published},

tppubtype = {phdthesis}

}