DUGONG (DUGONG DUGON) ABUNDANCE ALONG THE ANDAMAN COAST OF THAILAND

In 2000 and 2001, dugong abundance was estimated using aerial surveys in three provinces along the Andaman coast of Thailand. A microlite aircraft was used to fly aerial transects over seagrass areas. All surveys were done during rising tides as the dugongs came to the seagrass beds to feed. The largest population was found in Trang province. In Trang, the total number of sightings during 22 surveys was 264, out of which 31.5% were single dugongs. The largest group seen in 2000 was 30, and in 2001, 53. The maximum number of calves seen in one day was 13. The best minimum estimate of population abundance is 123 animals (CV = 60.8%) in Trang province. Higher numbers of dugong sightings and group sizes corresponded with higher tides until water turbidity impeded sightings after the highest spring tide. In other areas the number of animals seen was too small for population estimates.     

Amaurornis phoenicurus and Ardeola bacchus as experimental definitive hosts for Capillaria philippinensis in Thailand.

Two species of fish-eating bird namely, Amaurornis phoenicurus and Ardeola bacchus were fed with infective larvae of Capillaria philippinensis in Gambusia holbrookii. Intestinal capillariasis was able to establish in all three A. phoenicurus and one of three A. bacchus. Prepatent period in A. phoenicurus ranged from 22 to 30 days, whereas in A. bacchus it was 16 days after infection. Auto-infection was observed in all susceptible birds and the protective immunity had developed in one of A. phoenicurus used.     

Eine neueThomsonia-Art (Araceae) aus Thailand

A new species,Thomsonia sumawongii Bogner, is described from Thailand. Relationships toTh. napalensis and betweenThomsonia, Pseudodracontium andAmorphophallus are discussed.Allopythion hookeri Schott has to be eliminated as dubious.

     

Microdemographic variation and family composition in four thai villages

Examination of Thai ethnographic materials highlights several problems in comparative analysis of social processes that are population linked. Marked differences in family composition among four Central Thai villages are shown to arise primarily from a common family system operating on different underlying sociocultural and demographic processes. Satisfactory analysis requires detailed demographic data, information on other sociocultural processes, and a formal model of family dynamics relating the demographic to the other kinds of data. Lack of even one of these three components may make comparison meaningless. Demographic anthropology and historical demography provide complementary data well suited to anthropological studies of social organization.     

Rotifera from Peat-Swamps in Phuket Province,Thailand, with the Description of a New Colurella Bory de St. Vincent

The rotifer fauna of three peat-swamps in Phuket province, southern Thailand was investigated. A total of 77 species is identified, 12 of which are new to Thailand. A new species, Colurella sanoamuangae n. sp., is described. The zoogeography of the registered species is discussed.     

Biology of Clupeichthys aesarnensis (Clupeidae) in Ubolratana Reservoir,Thailand, with Special Reference to Food and Feeding Habits

The freshwater sardine Clupeichthys aesarnensis is a zooplanktivore like many clupeids. In Ubolratana reservoir, Thailand, it feeds selectively on larger zooplankters, especially Cladocera and to a lesser extent on Copepoda. Other zooplankters are also consumed together with both living and dead insects and occasionally its own young. It feeds during the day. Our results indicate that the slight seasonal differences in food consumed probably reflects differences in availability at different seasons and sites. The fish grows in weight, as expected, at a higher rate than the cube of its length. The condition factor is the same for males and females and shows some seasonal variation. Data on fecundity and gonadosomatic index mark this fish as highly fecund and a year-round spawner. Its short life span, favourable growth and high fecundity make it a valuable source of cheap protein. In 1990, 17% (about 300 tons) of the fish catch from Ubolratana came from this fish.     

Species richness of the Cladocera (Branchiopoda: Anomopoda and Ctenopoda) in southern Thailand, and its complementarity with neighboring regions

Seventy-two cladoceran species from southern Thailand include eleven first records. Species accumulation curves were used to estimate the total number of species present, and Chaos estimator was used to extrapolate the species number observed in 212 samples to the total number present. This S*max amounted to 76.06 species, with a low ratio of variance/estimator. Cladoceran faunas were compared by a complementarity index at three levels: between habitat types, between different zones of Thailand, and between Thailand and other countries. The geographical gradient was quite strong, but because not all areas have been studied to the same degree and with the same taxonomic accuracy, some comparisons are robust while others are not.     

Severity-related molecular differences among nineteen strains of dengue type 2 viruses

Comparative nucleotide sequencing was carried out on dengue type 2 virus (DEN-2) strains isolated from patients in Northeast Thailand during the epidemic season in 1993. The patients exhibited different clinical manifestations ranging from dengue fever (DF) to dengue haemorrhagic fever (DHF)/dengue shock syndrome (DSS). The results classified 19 DEN-2 strains into 3 subtypes according to nonsynonymous amino acid replacements. The strain isolated from a DSS patient eliciting secondary serological response belonged to subtype I, whereas 13 strains isolated from DHF patients with secondary response and 2 strains from DF patients with primary response belonged to subtype II. On the other hand, 3 strains isolated from DF cases evoking either primary or secondary response belonged to subtype III. These results suggest that subtype III virus infection could result in clinically milder manifestation irrespective of the serological response compared with subtype I or II viruses. The RNA secondary structure predicted for the 3' noncoding region showed 4 different structures (A, B, C, and D). The result also indicates that different subtypes of DEN-2 serotypes are circulating in a single epidemic in Thailand.     

Non-Carcinogenic Hazard Maps of Heavy Metal Contamination in Shallow Groundwater for Adult and Aging Populations at an Agricultural Area in Northeastern Thailand

The Hua-ruea sub-district has long been a major agricultural area of Thailand. Shallow groundwater from farm wells is a main source of drinking water for most locals. This study assessed the human health hazards associated with consuming groundwater contaminated with heavy metals among adults age 15–60 years and the aging, greater than 60 years. Twelve groundwater wells were sampled in the Hua-ruea agricultural area. The results showed adults’ average groundwater consumption was high at 3.6 ± 2.1 L/day/person and for the aging group was 2.6 ± 1.0 L/day/person. The hazard quotients for As, Cu, Pb, and Zn exceeded 1 among both the adult and aging populations. Residents of the Hua-ruea subdistrict may be at risk of developing diseases from consumption of water contaminated with these four metals at seven of the 12 wells. These wells are located in intensely cultivated chili fields. All non-carcinogenic hazards of all heavy metals were higher in adults than for the aging population due to a higher intake rate of water by the former. One well had the highest hazard index, 91.8 and 66.2 for adults and the aging, respectively. This study suggested that local people living in intensively agricultural areas should take precautions before drinking contaminated groundwater.