A total of 1,039 fish individuals was collected from organic rice fields in Nakhon Phanom Province, northeast Thailand. The samples comprised 35 species, 28 genera, and 15 families. The community was dominated by cyprinids, which contributed 13 species and formed the largest share of total species richness. Of the recorded taxa, 15 species were considered dominant, with Esomus metallicus being the most abundant (13.28%). Only one non-native fish species recorded in the sampled area, namely Oreochromis niloticus. Most species (94.29%) were classified as Least Concern in terms of conservation status. However, Boraras urophthalmoides is listed as Near Threatened, while Betta smaragdina remains data deficient. The diversity indices suggested a relatively balanced community structure, with a Shannon-Wiener diversity index (H’) of 2.93, species richness (R) of 4.20, and evenness (E) of 0.91. In the feeding ecology, the dominant species were grouped into different trophic levels. Clupeichthys aesarnensis was mainly found to feed on zooplankton, while Parambassis siamensis showed a carnivorous feeding habit. Most of the remaining dominant species were classified as omnivores with mixed diets. The results indicated that organic rice fields are found to be capable of supporting fish communities with a range of feeding strategies. It suggested that these habitats may help to maintain local fish diversity and have some role in supporting biodiversity within agricultural landscapes.

View online