Saifullah A. Jaaman

University of Malaysia, Terengganu | umt · Institute of Oceanography and Environment - INOS

Long-term monitoring of sea turtle aggregations is critical for understanding the impacts of environmental changes on their population health and habitat suitability. Brunei Bay is a significant foraging ground for green turtles in the South China Sea. We analyzed the body size, hematology and body condition of green turtles for their health status...

The study of the food and feeding habits of fishes is crucial in understanding their ecology. Food and feeding habits of the 30 fish species belonging to 22 families from Bukit Sari and Awat-awat of Lawas in the Bay of Brunei were studied on 11th February 2020 and 12th February 2020 respectively. Samples were collected using “Kabat” nets, casting n...

Sobri MF, Jaaman SA, Mohamed Z, Muda AM, Rashid MASA, Zhang X. 2022. Identifying the hotspot area of Indo-Pacific humpback (Sousa chinensis) and Irrawaddy (Orcaella brevirostris) dolphins in Matang waters, Perak, Malaysia. Biodiversitas 23: 6106- 6113. The Indo-Pacific humpback (Sousa chinensis) and Irrawaddy (Orcaella brevirostris) dolphins are co...

There is limited information on Irrawaddy dolphins (Orcaella brevirostris) in the Bay of Brunei, Brunei Darussalam. This research was carried out from 2016 to 2018 to determine the water surface behaviour of Irrawaddy dolphins in the bay, the relationship between behaviour and abiotic factors and the number of individuals displaying the behaviour....

Behavioural observation and acoustic recordings of Irrawaddy dolphins (Orcaella brevirostris) were performed simultaneously in Brunei Bay, Malaysia. Surface behavioural observations were classified into four categories: travelling, foraging, socialising, and milling. A total of 8.43 hours of acoustic recordings were used to retrieve four different...

The uniqueness of the Bay of Brunei makes it an ideal place to be inhabited by Irrawaddy dolphins. However, the increasing potential impacts of anthropogenic factors and environmental changes on the dolphins are alarming. The objectives of this study were to determine the seasonal occurrence and distribution, and to estimate the group size of Irraw...

Seasonal variations in total mercury concentrations [Hg] and trophic transfer through the food web were assessed using stable isotopic tracers for the Setiu Wetlands, Terengganu. The [Hg] measured in surface sediments and biota varied inversely between wet and dry seasons. Increased rainfall and water disturbance during the wet season are suggested...

The source parameters of Irrawaddy dolphins’ echolocation click in the Bay of Brunei were estimated. Analysis of eight parameters shows that the Irrawaddy dolphins produce broadband echolocation clicks with mean click duration of 21.1 ± 7.2 μs. The clicks had a mean peak-to-peak apparent source level (ASLpp) of 201.2 ± 7.3 dB re 1 μPa (N = 350), a...

Studies of the whistles of Irrawaddy dolphins (Orcaella brevirostris) have traditionally been restricted to analyses of the human audio range (below 20 kHz). In this study, broadband acoustic recordings of Irrawaddy dolphins in Brunei Bay were obtained using a sampling frequency of 512 kHz. Among the 984 whistles collected, eight (0.81%) high‐frequ...

Animal telemetry is a powerful tool for observing marine animals and the physical environments that they inhabit, from coastal and continental shelf ecosystems to polar seas and open oceans. Satellite-linked biologgers and networks of acoustic receivers allow animals to be reliably monitored over scales of tens of meters to thousands of kilometers,...

In this study, echolocation signals were recorded from a wild Irrawaddy dolphin (Orcaella brevirostris) in shallow water in the Bay of Brunei. During sound recording, a small fishing boat engine startled a nearby Irrawaddy dolphin and began chasing it on two occasions. Variations in the acoustic parameters were detected. When the Irrawaddy dolphin...

Background and Objectives: Barnacles are sessile organisms that attach themselves permanently to the surface of hard or living substrates. Turtle barnacles are also commonly found as epibionts on others marine organisms. Marine turtles are one example of living substrates colonised by barnacles. A sampling activity were conducted on April, 2016 obj...

The population of Irrawaddy dolphins in Brunei Bay, Malaysia is currently under threat by anthropogenic activities. This study is aimed at contributing information on population size, group composition, spatial occurrence and habitat preferences of this dolphin species in the bay area. A total of 36 inDviduals (adults) of Irrawaddy dolphins were id...

Studies of Irrawaddy dolphins' acoustics assist in understanding the behaviour of the species and thereby conservation of this species. Whistle signals emitted by Irrawaddy dolphin within the Bay of Brunei in Malaysian waters were characterized. A total of 199 whistles were analysed from seven sightings between January and April 2016. Six types of...

The population of Irrawaddy dolphins in Brunei Bay, Malaysia is little studied. This study aimed at contributing information on how abiotic and other factors influence different aspects of their behaviour displayed at the water surface. Several behaviours, i.e. foraging, travelling, foraging behind trawler, milling and socializing were observed dur...

Integration of the rookery connectivity, which includes historical connections among rookeries, and migratory connectivity assessing dispersal or migratory routes of marine animals are important for understanding dispersal and/or migration and its effect on the formation of genetic population structure. The migratory nature and long-distance moveme...

Barnacles are sessile organisms that attach themselves permanently to the surface of hard or living substrates. Turtle barnacles are also commonly found as epibionts on others marine organisms. Marine turtles are one example of living substrates colonised by barnacles. A sampling activity were conducted on April 2016 objectively to observe the barn...

Background and Objectives: Barnacles are sessile organisms that attach themselves permanently to the surface of hard or living substrates. Turtle barnacles are also commonly found as epibionts on others marine organisms. Marine turtles are one example of living substrates colonised by barnacles. A sampling activity were conducted on April, 2016 obj...

An overview on by-catch of dugongs (Dugong dugon) among fishermen in the Malaysian waters of Brunei Bay

Malaysia provides nesting rookeries and foraging grounds for the critically endangered hawksbill turtle (Eretmochelys imbricata), and a number of important foraging grounds have been identified for hawksbill turtles in Malaysia to date. This study reports the first record of juvenile hawksbill turtle at Brunei Bay (a distance of 60 km from the near...

The Irrawaddy dolphin (Orcaella brevirostris) locally known as “empesut” or “pesut” is the most common marine mammal and considered as the flagship species in Sarawak. Their habitats overlap with areas of intensive human activities. A study was conducted in Rajang River from April 2009 to October 2010 using a modified strip-transect boat survey whe...

Knowledge of genetics composition and growth stages of endangered green turtles, as well as the connectivity between nesting and foraging grounds is important for effective conservation. A total of 42 green turtles were captured at Brunei Bay with curved carapace length ranging from 43.8 to 102.0 cm, and most sampled individuals were adults and lar...

Two species of cetaceans reside in Cowie Bay, Sabah; the Indo-Pacific humpback dolphin (Sousa chinensis) and the Irrawaddy dolphin (Orcaella brevirostris). Between April 2008 and March 2009, 41 days were spent onboard a survey boat to observe dolphin behaviour in the bay. Mixed groups of humpback and Irrawaddy dolphins were observed in the area whe...

Seagrass is a valuable marine ecosystem engineer. However, seagrass population is declining worldwide. The lack of seagrass research in Malaysia raises questions about the status of seagrasses in the country. The seagrasses in Lawas, which is part of the coral-mangrove-seagrass complex, have never been studied in detail. In this study, we examine w...

Marine mammal searches were opportunistically conducted during the East Coast Johor Scientific Expedition (ECJSE) on 21-30 May 2012, on a live-on-board (LOB) diving vessel, MV BLACK PEARL. The expedition was designed mainly to survey coral reef ecosystems and water quality. Daylight visual observations of the sea were undertaken during sailing and...

A population of Irrawaddy dolphins (Orcaella brevirostris) occurs in Cowie Bay, southwest of Sabah. Boat-based photo-identification surveys were conducted over a period of 12 months, from October 2009 to September 2010. Photographs were first sorted according to quality and according to physical appearance of Irrawaddy dolphins’ dorsal fin. They we...

A series of boat surveys were conducted from April to September 2008. This work evaluated the effects of boats on Indo-Pacific Humpback and Irrawaddy dolphins. The types of boats, dolphins' interactions towards various types of boat and vessel-dolphin distance under different intensities were measured. The absence of boats sailing in the bay was co...

The magnitude and sustainability of incidental catches of marine mammals in fisheries was investigated in Sabah and Sarawak, East Malaysia, using a combination of interview surveys and observer trips on fishing boats. These fisheries involve around 15,000 registered fishing boats and generate annual landings of around 350,000 tonnes. Between March...

Marine mammals are endangered species. Marine mammals have 4 orders, which are Cetacean, Sirenian, Piniped and Marine Fisiped. Doplhins are one of suborder in Cetacean. The development of dolphin’s watcher expert system will help the expert or their research assistant to identify the species of the dolphins in Malaysia. This expert system (ES) is d...

The principal water bodies of Peninsular Malaysia are the Straits of Malacca and the South China Sea. Although the seas are known to be nutrient rich and able to support a remarkable diversity of species, the distribution and abundance of marine mammals is poorly known. Studies on marine mammals at Universiti Malaysia Sabah and the creation of Mala...