Short communication: Dugong’s presence

confirmation in Bintan Island based on local

ecological knowledge
1
Fadhliyah Idris, 1Ita Karlina, 2,3
Sekar M. C. Herandarudewi, 1,3
Aditya H.
Nugraha

1
Department of Marine Science, Raja Ali Haji Maritime University, Tanjungpinang,
Indonesia; 2 Research Center of Oceanography, Indonesian Institute of Sciences, Jakarta,
Indonesia; 3 LAMINA, Indonesian Seagrass Foundation, Depok, Indonesia. Corresponding
author: A. H. Nugraha, adityahn@umrah.ac.id

Abstract. Dugong (Dugong dugon) population continues to decline due to the high pressure coming from
the environment and hunting by humans. Bintan Island is one of the D. dugon habitats in Indonesia. This
study aims to confirm the existence of dugongs and identify threats to the survival of dugongs through
interviews with local communities based on local ecological knowledge. The study was conducted at five
locations on Bintan Island which included Berakit, Pengudang, Teluk Bakau, Kelam Pagi and Kelong. The
results obtained indicate that the majority of respondents of Berakit (100%) and Kelong (78%) have
seen the presence of D. dugon in nature with a fairly frequent level of intensity. The threat to the
survival of D. dugon on Bintan Island originates from the existence of fishing gear such as nets and
fishing traps. Besides, at several locations it is still in the habit of the communities to hunt D. dugon and
this is one of the biggest threats to the D. dugon species conservation.
Key Words: conservation, diversity, Dugong dugon, marine mammals.

Introduction. Dugong (Dugong dugon) is one of the mega fauna living in the marine
ecosystem, which belongs to the class of mammals. According to the data released by
IUCN, dugong is a species threatened by extinction, its population being in a continuous
decline, due to several factors including a very low reproductive rate anthropogenic
pollution consequences and excessive hunting (Marsh et al 2015).
The distribution of dugong in the world covers the Indo-Pacific region and some
parts of Africa. Indonesian waters are an important habitat for dugong populations in the
world. The distribution of dugongs in Indonesian waters is very broad, according to the
results of a research that has been carried out, covering the Gulf of Cendrawasih,
Padaido, Biak, Maluku, Aru Islands, Flores, Ujungkulon, Sunda Strait, Bangka-Belitung,
Bintan, Kalimantan (Marsh et al 2002). Due to the breadth of Indonesian waters
information related to dugong population estimates is very scarce. Bintan Island is one of
the islands in the Riau Islands region, located in the western part of Indonesia, which is
geographically bordered by Malaysia and Singapore. Dugong population in the waters of
Bintan Island was reported as being mostly extinct.
Further observation is needed regarding the existence of dugong species in the
waters of Bintan Island to ensure its population distribution and habitat preservation. D.
dugon observations can be done with various methods such as aerial surveys, tracing
food traces in the seagrass ecosystem and hydroacoustics.
Another method that can be used to confirm the presence of D. dugon in the
Bintan Island waters is to use local ecological knowledge principles (Adulyanukosol &
Poovachiranon 2006; Cullen-Unsworth et al 2018). Interviewing the community, based
on the principle of valuing the local ecological knowledge, is considered to be the most
effective method for observing the existence of dugongs in nature (Cullen-Unsworth et al
2018). This method can be used in the context of preliminary studies related to

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monitoring the population of dugongs in their habit, given the appearance of D. dugon
that makes them difficult to identify. The principle of local ecological knowledge has been
widely used, especially in the context of creating ecosystem conservation areas (Frans &
Augé 2016).

Material and Method. The research was carried out on Bintan Island covering five
locations: Pengudang, Berakit, Teluk Bakau, Kelong and Kelam Pagi (Figure 1). The
interview sites were selected based on the frequency of their past apparitions in the
areas the most likely to be their habitats. The interview process was conducted with
people involved in sea related activities. In total, 56 respondents were successfully
interviewed in the current study, the process being based on the rapid rural appraisal
(RRA) method (Juraij 2016). The questions included the dugong sighting frequency and
locations, the type of fishing gear interfering with the dugong’s survival conditions and
the community habit of hunting and eating dugong.

Figure 1. Research map location.

Results and Discussion

D. dugon encounter. Observations related to the encounter of Dugong on Bintan Island

were carried out by interviewing the communities in five different locations. Based on the
interview results, data concerning the frequency of D. dugon presence in Bintan Island
was presented in (Table 1).

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 Table 1
The results of interviews related to the appearance of Dugong dugon on Bintan Island

Knowing D. dugon Occurrence rate Habitat

Region Seagrass Other
Yes No Frequent Infrequent Unknown
ecosystem habitat
Berakit 100% - 100% 0 100% - -
Pengudang 100% - 11.11% 88.89% 78% - 22%
Teluk
100% - 0 100% 0 - 100%
Bakau
Kelam Pagi 100% - 0 100% 81% - 19%
Kelong 100% - 67% 33% 89% - 11%

Based on the results of interview, generally all respondents already knew about D. dugon
and were able to distinguish them from other types of marine animals. D. dugon
occurrences were still frequently found in Berakit and Kelong areas. The majority of
respondents having sea related activities reported frequent apparitions of D. dugon in
these waters (Table 1), but also in Pengudang waters, although with a lower incidence
rate. Communities from the areas of Teluk Bakau and Kelam Pagi reported rare D. dugon
apparitions in the waters. The respondents explained that they generally emerge into the
quiet waters.
In the communities of Bintan Island it is generally known that D. dugon has a
connection with the existence of seagrass ecosystems. The results of interviews showed
that most of the respondents saw the existence of D. dugon in surrounding seagrass
ecosystems (Table 1). The majority of the people already knew that seagrass is a food
resource for D. dugon, which are highly dependent on seagrass ecosystems
(Adulyanukosol et al 2004; Tol et al 2016).
The exact locations of the D. dugon occurence in North Bintan were in Berakit and
also between Berakit and Sumpat Island. The waters of North Bintan (Berakit and
Pengudang) and Kelong Island were assumed to have a fairly good seagrass ecosystem
condition, with no less than 10 species of seagrass identified in Bintan Island (Kawaroe et
al 2016). Generally, seagrass species preferred by D. dugon are Halodule, Halophila and
Syringodium, all of them abounding in Pengudang and Berakit, but also around Teluk
Bakau (Juraij et al 2014; Nugraha et al 2019).

D. dugon threat. Communities from the study area explained that the presence of D.
dugon populations in nature tends to decrease in number. This phenomenon is due to the
many threats to the D. dugon survival (Table 2).

Table 2
The activities that threaten the survival of Dugong dugon in the observation area

Threat Berakit Pengudang Teluk Bakau Kelong Kelam Pagi

D. dugon has D. dugon
No threats D. dugon
been found was once
were found Many fishing was once
Fisheries trapped in a found tied
from fisheries activities found tied to
fish trap and to fishing
activities fishing nets
caught in a net nets
There were
There was respondents There was
Hunt found a D. who claimed of Non-existent found a D. Non-existent
dugon hunt hunted D. dugon hunt
dugon
Medium Low Low
Low intensity
intensity for intensity for intensity for
Stranded for stranded D. Non-existent
stranded D. stranded D. stranded D.
dugon
dugon dugon dugon

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 Figure 2. Spatial intensity threats of Dugong dugon in Bintan Island based on fishing
activity, hunting and stranding history.

Based on the information presented in Table 2, fishery activity is one of the factors that
threaten the survival of dugongs in waters. The presence of fishing nets in the sea can
cause D. dugon to be entangled in a net. Pengudang area is one of the most productive
areas in fishing activities, where many types of fishing gear are deployed by fishermen.
There were some incidents, such involuntary captures of dugongs in a net or a kelong.
Some people in the research area have consumed D. dugon. The community
claimed that D. dugon meat was obtained by hunting or buying it. Based on observations,
dugong hunting was still frequent in the Berakit and Kelong areas. Some people coming
from the coastal tribes and who have settled in the Berakit and Kelong areas, still carry
out dugong hunting activities, both for consumption and for taking fangs and tears. The
persistence of hunting protected animals is an indicator of a lack of understanding of the
species conservation importance (Coll et al 2014). The economic condition of the
community is thought to be one of the factors triggering such fishing activities (Augé et
al 2012).
In addition to the threats that presented in Table 2, other threats can originate
from pollution and tourism activities. Currently, the area of Teluk Bakau has many
resorts and other tourism activities. These factors could determine the dugong’s
migration. The dugong has the ability to migrate over long distances (Sheppard et al
2006). It is supposed that dugongs originating from Bintan Island can migrate as far as
far the Johor Malaysia waters, in accordance with the results of the research of Hashim et
al (2017). Figure 2 is a compilation of all the information in Table 2, resulting in a risk
map of the dugong’s habitat sustainability in Bintan Island. Hunting activities are
considered to represent the most significant risk for the D. dugon survival at Bintan
Island.
A national action plan for D. dugon conservation in Indonesia was elaborated and
it was promoted through a decree of the Ministry of Marine Affairs and Fisheries (MMAF
2018). The results of this study can be used as a way to encourage the government to

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carry out a national action plan well through collaboration between stakeholders, through
various activities, such as public awareness and monitoring of D. dugon populations so
that it is hoped that its sustainability in nature remains protected.

Conclusions. A clear action plan is needed regarding the monitoring of D. dugon

populations at Bintan Island, by scheduling surveys based on several methods. The
threats to the survival of D. dugon in some areas require immediate solutions supported
by coordination between stakeholders (government, universities, research institutes,
NGOs, communities) in implementing the national action plan for D. dugon conservation.

Acknowledgements. The authors would like to thank the Research Grant Faculty of
Marine Science and Fisheries Raja Ali Haji Maritime University for support in this research.

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Received: 30 December 2019. Accepted: 18 March 2020. Published online: 26 March 2020.
Authors:
Fadhliyah Idris, Raja Ali Haji Maritime University, Department of Marine Science, 29111 Tanjungpinang,
Indonesia, e-mail: fadhliyahidris87@gmail.com
Ita Karlina, Raja Ali Haji Maritime University, Department of Marine Science, 29111 Tanjungpinang, Indonesia,
e-mail:itakarlina@umrah.ac.id
Sekar Mira Cahyopeni Herandarudewi, Research Center of Oceanography, Indonesian Institute of Sciences,
14430 Jakarta, Indonesia, email: rrsekarmira2@gmail.com
Aditya Hikmat Nugraha, Raja Ali Haji Maritime University, Department of Marine Science, 29111 Tanjungpinang,
Indonesia, e-mail: adityahn@umrah.ac.id
This is an open-access article distributed under the terms of the Creative Commons Attribution License, which
permits unrestricted use, distribution and reproduction in any medium, provided the original author and
source are credited.
How to cite this article:
Idris F., Karlina I., Herandarudewi S. M. C., Nugraha A. H., 2020 Short communication: Dugong’s presence
confirmation in Bintan Island based on local ecological knowledge. AACL Bioflux 13(2):651-656.

AACL Bioflux, 2020, Volume 13, Issue 2.

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