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Fulltext Feeding ecology and reproductive biology of small coastal sharks in Malaysian waters

Lim KC, Then AY, Loh KH

PeerJ, 2023;11:e15849.
PMID: 37637173 DOI: 10.7717/peerj.15849

Small coastal demersal sharks form a major proportion of the sharks landed in Malaysia. However, little is known about their feeding ecology and reproduction. This study sought to elucidate the dietary patterns, role of ontogeny in prey consumption, and reproductive biology of four dominant small demersal shark species in Malaysian waters: the Hasselt's bamboo shark, Chiloscyllium hasseltii; brownbanded bamboo shark, C. punctatum; spadenose shark, Scoliodon laticaudus; and Pacific spadenose shark, S. macrorhynchos. Dietary analyses revealed a high overlap in prey taxa consumed; clear resource partitioning among co-occurring species based on the percentage Prey-specific Index of Relative Importance (%PSIRI), with higher fish %PSIRI for Chiloscyllium hasseltii, higher cephalopod %PSIRI for C. punctatum, and higher crustacean %PSIRI for both Scoliodon species; and an ontogenetic diet shift, seen through changes in prey size. Based on the examination of reproductive organs, the results showed larger sizes at maturity for males compared to females for all four species; no obvious reproductive cycles, based on hepatosomatic and gonadosomatic indices for all species; female bias in the sex ratio of the embryos of Scoliodon species; and increased reproductive output (number of eggs or embryos and size of eggs) with larger female size for C. hasseltii and Scoliodon species. The partitioning of food resources minimizes direct competition for food and supports coexistence within shared coastal habitats. The reproductive strategies of these small coastal sharks appear to be favorable for supporting short-term population productivity; although a reduction in fishing pressure, especially from bottom trawlers, is essential for the long-term sustainable use of these sharks.

Matched MeSH terms: Ecology*
Fulltext Anopheline mosquitos of northwest coastal Malaysia

Jaal Z, MacDonald WW

Southeast Asian J. Trop. Med. Public Health, 1992 Sep;23(3):479-85.
PMID: 1488703

Collections of adult anopheline mosquitos were made from a cow-baited trap in nine coastal villages located along nearly 160km of northwest peninsular Malaysia. Two collections, separated by 1.5 to 6 months, were made at each site. Nearly 6,000 anophelines of 19 species were collected. The dominant species were Anopheles peditaeniatus. An. sinensis, An. subpictus and An. lesteri paraliae. Small numbers of the malaria vectors An. maculatus (at one site) and An. campestris (at four sites) were collected, but no An. sundaicus were recorded.

Matched MeSH terms: Ecology
Fulltext Lurking in the dark: Cryptic Strongyloides in a Bornean slow loris

Frias L, Stark DJ, Lynn MS, Nathan SK, Goossens B, Okamoto M, et al.

Int J Parasitol Parasites Wildl, 2018 Aug;7(2):141-146.
PMID: 29988792 DOI: 10.1016/j.ijppaw.2018.03.003

Within host communities, related species are more likely to share common parasitic agents, and as a result, morphological similarities have led researchers to conclude that parasites infecting closely related hosts within a community represent a single species. However, genetic diversity within parasite genera and host range remain poorly investigated in most systems. Strongyloides is a genus of soil-transmitted nematode that has been reported from several primate species in Africa and Asia, and has been estimated to infect hundreds of millions of people worldwide, although no precise estimates are available. Here we describe a case of infection with a cryptic species of Strongyloides in a Bornean (Philippine) slow loris (Nycticebus menagensis) living within a diverse community of several primate species in the Lower Kinabatangan Wildlife Sanctuary, Malaysian Borneo. Fresh fecal samples were collected from five primate species and nematode larvae cultured from these samples were selected for phylogenetic analyses. Sequences obtained for most larvae were identified as S. fuelleborni, grouping into three different clusters and showing no aggregation within specific hosts or geographic location. In contrast, a set of parasite sequences obtained from a slow loris clustered closely with S. stercoralis into a different group, being genetically distinct to sequences reported from other primate hosts, humans included. Our results suggest that although S. fuelleborni infects all haplorrhines sampled in this primate community, a different species might be infecting the slow loris, the only strepsirrhine in Borneo and one of the least studied primates in the region. Although more data are needed to support this conclusion, we propose that Strongyloides species in primates might be more diverse than previously thought, with potential implications for ecological and evolutionary host-parasite associations, as well as epidemiological dynamics.

Matched MeSH terms: Ecology
The phlebotomine sandflies of Malaysia (Diptera: Psychodidae)

Rudnick A, Garcia R, Jeffery J, Marchette NJ, MacVean DW

Southeast Asian J. Trop. Med. Public Health, 1971 Mar;2(1):86.
PMID: 5112346
Matched MeSH terms: Ecology
Fulltext Spatio-temporal ecology of sympatric felids on Borneo. Evidence for resource partitioning?

Hearn AJ, Cushman SA, Ross J, Goossens B, Hunter LTB, Macdonald DW

PLoS One, 2018;13(7):e0200828.
PMID: 30028844 DOI: 10.1371/journal.pone.0200828

Niche differentiation, the partitioning of resources along one or more axes of a species' niche hyper-volume, is widely recognised as an important mechanism for sympatric species to reduce interspecific competition and predation risk, and thus facilitate co-existence. Resource partitioning may be facilitated by behavioural differentiation along three main niche dimensions: habitat, food and time. In this study, we investigate the extent to which these mechanisms can explain the coexistence of an assemblage of five sympatric felids in Borneo. Using multi-scale logistic regression, we show that Bornean felids exhibit differences in both their broad and fine-scale habitat use. We calculate temporal activity patterns and overlap between these species, and present evidence for temporal separation within this felid guild. Lastly, we conducted an all-subsets logistic regression to predict the occurrence of each felid species as a function of the co-occurrence of a large number of other species and showed that Bornean felids co-occurred with a range of other species, some of which could be candidate prey. Our study reveals apparent resource partitioning within the Bornean felid assemblage, operating along all three niche dimension axes. These results provide new insights into the ecology of these species and the broader community in which they live and also provide important information for conservation planning for this guild of predators.

Matched MeSH terms: Ecology
Fulltext The ecology of anopheline mosquitos in northwest coastal Malaysia: host preferences and biting-cycles

Jaal Z, Macdonald WW

Southeast Asian J. Trop. Med. Public Health, 1993 Sep;24(3):530-5.
PMID: 8160064

The host preferences of eight species of anophelines were studied in two coastal Malaysian villages, Kampung Permatang Rawa and Sungai Udang Kecil, by seven 12-hour catches in each village. Collections were made concurrently from a human-baited net trap, a cow-baited net trap and by human-bait landing catches. Anopheles campestris was attracted almost equally to man and cow, but An. lesteri paraliae, An. nigerrimus, An. peditaeniatus, An. sinensis, An. indefinitus, An. subpictus and An. vagus showed a strong preference for the cow bait. The human-bait landing catches were more productive than the human-baited net trap, which attracted very few mosquitos. Seven more all-night catches were made at each village employing only the cow-baited trap, and the combined data were used to plot the biting-cycles of each species at each site. Although the biting-cycles at the two localities were in general agreement, there were notable differences. At Sungai Udang Kecil, where the collection site was relatively sheltered, several species showed a steady decline in numbers from sunset to sunrise. At Kampung Permatang Rawa, on the other hand, where the site was more exposed and close to the sea, the same species showed a bimodal pattern of activity with an early evening peak followed by a decline then a period of increased activity before sunrise rising to a second, lesser peak at 0500-0600 hours.

Matched MeSH terms: Ecology*
Fulltext The ecology of anopheline mosquitos in northwest coastal Malaysia: larval habitats and adult seasonal abundance

Jaal Z, Macdonald WW

Southeast Asian J. Trop. Med. Public Health, 1993 Sep;24(3):522-9.
PMID: 8160063

Collections of anopheline mosquitos were made twice monthly for 13 months from a cow-baited trap in two villages, Kampung Permatang Rawa and Sungai Udang Kecil, on mainland coastal Penang, Malaysia. Each collection period was six hours from sunset. Unquantified larval collections were made regularly in each area. Although the villages were only about 50km apart, and each had extensive, irrigated rice-fields in its vicinity, the species abundance and the seasonal fluctuations differed significantly. In Kampung Permatang Rawa Anopheles sinensis and An. peditaeniatus were dominant in prevalence, whereas in Sungai Udang Kecil An. indefinitus and An. lesteri paraliae were most common and An. peditaeniatus was relatively rare. The rice growing schedules in the two areas differed, but there was a moderate correlation between the abundance of several species and the rice-growing pattern. There was no correlation at either site with rainfall.

Matched MeSH terms: Ecology*
Arbovirus infections in Sarawak: further observations on mosquitoes

Macdonald WW, Smith CE, Dawson PS, Ganapathipillai A, Mahadevan S

J Med Entomol, 1967 May;4(2):146-57.
PMID: 4383192
Matched MeSH terms: Ecology*
Modeling the significance of green orientation and culture on green innovation performance: moderating effect of firm size and green implementation

Bhatti SM, Al Mamun A, Wu M, Naznen F, Kanwal S, Makhbul ZKM

Environ Sci Pollut Res Int, 2023 Sep;30(44):99855-99874.
PMID: 37615918 DOI: 10.1007/s11356-023-29353-4

The current global trend in sustainable business practices is to optimize green innovation performance. To protect the environment and maintain their own survival, organizations must strengthen their green innovation capabilities. Drawing on the recourse-based view and ecology modernization theory (EMT), this study examines the direct effect of green strategic orientations, green entrepreneurial orientation, green market orientation, green innovation orientation, and green organizational culture on the firm's green innovation capability, as well as the mediating effect of green innovation capability on the relationship of these four factors and green innovation performance. Besides, this study also explored the moderating effects of green management system implementation and firm size on the association between green innovation capability and green innovation performance. To test the hypothesized model, a questionnaire survey was administered to gather responses from 293 medium-sized and large manufacturing firms operating in Pakistan. The partial least squares method was used for data analysis. The results revealed that green entrepreneurial orientation, green market orientation, green innovation orientation, and green organizational culture positively impacted green innovation capability, which subsequently positively influenced green innovation performance. Moreover, effective implementation of green management systems can bolster the effect of green innovation capability on green innovation performance, and the mediating effect of green innovation capability has also been confirmed. These indicated that the management of medium and large manufacturing firms operating in Pakistan should focus on encouraging green innovation and training employees regarding the latest eco-friendly technologies to attain performance and sustainable development goals. Policymakers should implement green business development programs and offer rewards or penalties for promoting compliance. The present study contributes greatly to the literature by applying EMT as an alternative to address the mediating role of green innovation capability and the moderating effect of green management system implementation in enhancing firms' green innovation performance.

Matched MeSH terms: Ecology
The effects of rainfall on trombiculid (Acarina:trombiculidae) larval populations in peninsular Malaysia

Gentry JW, Phang OW, Manikumaran C

Southeast Asian J. Trop. Med. Public Health, 1977 Jun;8(2):217-20.
PMID: 918713

Studies of larval mite populations along transects, as measured with black plates, were conducted in forest and grassland habitats for a period of 67 weeks. Larvae of both Leptotrombidium (Leptotrombidium) deliense and L. (L.) fletcheri were influenced greatly by rainfall, with the larvae being abundant and easily collected during periods of heavy rainfall and difficult or impossible to collect during dry periods. Simulated rainfall maintained larval populations for longer periods during dry weather.

Matched MeSH terms: Ecology
Rickettsioses (tick typhus, Q-fever, urban typhus) in Malaya

Marchette NJ

J Med Entomol, 1966 Jan;2(4):339-71.
PMID: 5951938
Matched MeSH terms: Ecology
On the radioactivity in the marine environment of the Straits of Malacca

Martin PH

Health Phys, 1978 Oct;35(4):574-5.
PMID: 748266
Matched MeSH terms: Ecology
Zonorchis robdollfusi sp. n. (Trematoda: Dicrocoeliidae)-a new trematode of squirrels in Sabah

Peters W, McDermott S

Southeast Asian J. Trop. Med. Public Health, 1973 Dec;4(4):579-81.
PMID: 4787658
Matched MeSH terms: Ecology
Fulltext Orangutans venture out of the rainforest and into the Anthropocene

Spehar SN, Sheil D, Harrison T, Louys J, Ancrenaz M, Marshall AJ, et al.

Sci Adv, 2018 06;4(6):e1701422.
PMID: 29963619 DOI: 10.1126/sciadv.1701422

Conservation benefits from understanding how adaptability and threat interact to determine a taxon's vulnerability. Recognizing how interactions with humans have shaped taxa such as the critically endangered orangutan (Pongo spp.) offers insights into this relationship. Orangutans are viewed as icons of wild nature, and most efforts to prevent their extinction have focused on protecting minimally disturbed habitat, with limited success. We synthesize fossil, archeological, genetic, and behavioral evidence to demonstrate that at least 70,000 years of human influence have shaped orangutan distribution, abundance, and ecology and will likely continue to do so in the future. Our findings indicate that orangutans are vulnerable to hunting but appear flexible in response to some other human activities. This highlights the need for a multifaceted, landscape-level approach to orangutan conservation that leverages sound policy and cooperation among government, private sector, and community stakeholders to prevent hunting, mitigate human-orangutan conflict, and preserve and reconnect remaining natural forests. Broad cooperation can be encouraged through incentives and strategies that focus on the common interests and concerns of different stakeholders. Orangutans provide an illustrative example of how acknowledging the long and pervasive influence of humans can improve strategies to preserve biodiversity in the Anthropocene.

Matched MeSH terms: Ecology
Fulltext Food taboos: their origins and purposes

Meyer-Rochow VB

J Ethnobiol Ethnomed, 2009;5:18.
PMID: 19563636 DOI: 10.1186/1746-4269-5-18

Food taboos are known from virtually all human societies. Most religions declare certain food items fit and others unfit for human consumption. Dietary rules and regulations may govern particular phases of the human life cycle and may be associated with special events such as menstrual period, pregnancy, childbirth, lactation, and -- in traditional societies -- preparation for the hunt, battle, wedding, funeral, etc. On a comparative basis many food taboos seem to make no sense at all, as to what may be declared unfit by one group may be perfectly acceptable to another. On the other hand, food taboos have a long history and one ought to expect a sound explanation for the existence (and persistence) of certain dietary customs in a given culture. Yet, this is a highly debated view and no single theory may explain why people employ special food taboos. This paper wants to revive interest in food taboo research and attempts a functionalist's explanation. However, to illustrate some of the complexity of possible reasons for food taboo five examples have been chosen, namely traditional food taboos in orthodox Jewish and Hindu societies as well as reports on aspects of dietary restrictions in communities with traditional lifestyles of Malaysia, Papua New Guinea, and Nigeria. An ecological or medical background is apparent for many, including some that are seen as religious or spiritual in origin. On the one hand food taboos can help utilizing a resource more efficiently; on the other food taboos can lead to the protection of a resource. Food taboos, whether scientifically correct or not, are often meant to protect the human individual and the observation, for example, that certain allergies and depression are associated with each other could have led to declaring food items taboo that were identified as causal agents for the allergies. Moreover, any food taboo, acknowledged by a particular group of people as part of its ways, aids in the cohesion of this group, helps that particular group maintain its identity in the face of others, and therefore creates a feeling of "belonging".

Matched MeSH terms: Ecology
Fulltext Socio-epidemiological and land cover risk factors for melioidosis in Kedah, Northern Malaysia

Abu Hassan MR, Aziz N, Ismail N, Shafie Z, Mayala B, Donohue RE, et al.

PLoS Negl Trop Dis, 2019 03;13(3):e0007243.
PMID: 30883550 DOI: 10.1371/journal.pntd.0007243

BACKGROUND: Melioidosis, a fatal infectious disease caused by Burkholderia pseudomallei, is increasingly diagnosed in tropical regions. However, data on risk factors and the geographic epidemiology of the disease are still limited. Previous studies have also largely been based on the analysis of case series data. Here, we undertook a more definitive hospital-based matched case-control study coupled with spatial analysis to identify demographic, socioeconomic and landscape risk factors for bacteremic melioidosis in the Kedah region of northern Malaysia.
METHODOLOGY/PRINCIPAL FINDINGS: We obtained patient demographic and residential information and clinical presentation and medical history data from 254 confirmed melioidosis cases and 384 matched controls attending Hospital Sultanah Bahiyah (HSB), the main tertiary hospital of Alor Setar, the capital city of Kedah, during the period between 2005 and 2011. Crude and adjusted odds ratios employing conditional logistic regression analysis were used to assess if melioidosis in this region is related to risk factors connected with socio-demographics, various behavioural characteristics, and co-occurring diseases. Spatial clusters of cases were determined using a continuous Poisson model as deployed in SaTScan. A land cover map in conjunction with mapped case data was used to determine disease-land type associations using the Fisher's exact test deploying simulated p-values. Crude and adjusted odds ratios indicate that melioidosis in this region is related to gender (males), race, occupation (farming) and co-occurring chronic diseases, particularly diabetes. Spatial analyses of disease incidence, however, showed that disease risk and geographic clustering of cases are related strongly to land cover types, with risk of disease increasing non-linearly with the degree of human modification of the natural ecosystem.
CONCLUSIONS/SIGNIFICANCE: These findings indicate that melioidosis represents a complex socio-ecological public health problem in Kedah, and that its control requires an understanding and modification of the coupled human and natural variables that govern disease transmission in endemic communities.

Matched MeSH terms: Ecology
Specimens as primary data: museums and 'open science'

Schilthuizen M, Vairappan CS, Slade EM, Mann DJ, Miller JA

Trends Ecol Evol, 2015 May;30(5):237-8.
PMID: 25813120 DOI: 10.1016/j.tree.2015.03.002
Matched MeSH terms: Ecology/methods*
Fulltext Marine mammals in the waters of East Coast Johor, Malaysia

Jaaman, S.A., Mohamed, C.A.R.

ASM Science Journal, 2014;8(2):143-149.
MyJurnal

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 stopping/anchored from the most upper open-deck of the vessel. The survey resulted in two sightings of long-beaked common dolphins (Delphinus capensis), each at Pulau Aur and Pulau Tinggi. Both observations were brief (< 5 minutes) and were made when the vessel was anchored. Based on anecdotal evidences, skeletal remains and previous surveys, the vulnerable dugong, Indo-Pacific bottlenose, Indo-Pacific humpback, Irrawaddy and long-beaked common dolphins, the false killer and pygmy killer whales, and the baleen whales are known to occur in the East Coast Johor waters, at least occasionally. The low sighting rate with marine mammals during this survey is highly likely caused by the survey design and also may be due to the environmental conditions and ecological factors. Dedicated and periodical boat and aerial surveys for marine mammals need to be conducted to determine species diversity and to understand the seasonality, habitat use, and social interactions of the marine mammal populations in the area. The findings will be most useful for marine park and fisheries authorities to plan conservation management strategies for marine mammals and promote their conservation through eco-tourism activities.

Matched MeSH terms: Ecology
The Effects of Amplification and Dilution Agent in Transmitting Sin Nombre Virus (SNV) in Deer Mouse Population

Lloyd Wen Feng Lee, Mohd Hafiz Mohd

MATEMATIKA, 2020;36(2):85-98.
MyJurnal

1Malaysia
2 (UKM)43600 Bangi, Selangor, Malaysia
∗Corresponding author:

Numerous studies have linked biodiversity with zoonotic disease control. However, researchers have warned against simply believing that the increase in biodiversity can reduce the infection disease in the community. They proposed that amplification effect (increase in biodiversity accompanied by an increase in disease prevalence) might sometimes occur. Thus, we formulated a deterministic model to consider the impact of an amplification or dilution agent on the SNV transmission in the deer mouse population. Bifurcation analysis was carried out to examine the combined influences of the environmental carrying capacity, the interspecific competition strength and the impact of amplification or dilution agent on the deer mouse population. Our results showed that the system with amplification agent required a higher carrying capacity or stronger interspecific strength to compensate for its amplification effect in suppressing the SNV prevalence; this situation explains the lack of reduction in SNV prevalence despite the presence of high biodiversity in some empirical studies. In this study, we highlight the importance of investigating the roles of the additional species in an assemblage to better understand their relationship with the SNV prevalence in deer mouse population.

Matched MeSH terms: Ecology
Fulltext Impacts of asymmetric biotic interactions and environmental factors on the presence-absence of multispecies

Ojonubah, James Omaiye, Mohd Hafiz Mohd

Pertanika Journal of Science & Technology, 2020;28(1):245-261.
MyJurnal

Interactions between multispecies are usual incidence in their habitats. Such interactions among the species are thought to be asymmetric in nature, which combine with environmental factors can determine the distributions and abundances of the species. Most often, each species responds differentially to biotic interactions and environmental factors. Therefore, predicting the presence-absence of species is a major challenge in ecology. In this paper, we used mathematical modelling to study the combined effects of biotic interactions (i.e. asymmetric competition) and environmental factors on the presence-absence of the species across a geographical region. To gain better insight on this problem, we performed invasion and numerical simulation analyses of the model of multispecies competitive dynamics. Different threshold values of competition coefficients were observed, which result in different phenomena; such as coexistence of species and priority effects. Consequently, we propose that asymmetric biotic interactions, combined with environmental factors can allow coexistence of relatively weak and strong species at the same location x.

Matched MeSH terms: Ecology

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