Cyclocheilichthys enoplos was reported throughout the survey area, from Bokeo in the Lao PDR in the north to the Mekong delta.

The migration pattern was found to be similar to Cirrhinus microlepis, with an upstream migration from Phnom Penh to the Khone Falls from November to February, and a downstream migration from May to August. The latter migration continues down into the Mekong delta area in Viet Nam until peak flooding in October-November. The two migrations mainly comprise juveniles and sub-adults, although the three stations closest to the Khone Falls have reported adults of 90 cm.

Above the Khone Falls, Cyclocheilichthys enoplos migrate upstream from April to September. It is probably a spawning migration as the fish are dominated by adults; also, mature Cyclocheilichthys enoplos bearing eggs were reported during that period by three stations in Xayaboury province. Juveniles and sub-adults are also caught in that section of the river.

Several reports from Cambodia stated that the juveniles and sub-adults migrated out of flooded areas and back upstream into the Mekong River during the period of receding water. At two stations, reports indicated that Cyclocheilichthys enoplos migrated down from the Tonle Sap River into the Mekong River. That information corresponds with the results of previous studies on the Tonle Sap River, where the species constitutes an important part of the catch between December and February (Lieng et al., 1995).

Above the Khone Falls, the first rainfall at the end of the dry season, as well as rising water levels and higher turbidity, were all reported to contribute to triggering the onset of the upstream migration.

The larger fish were reported to live in big pools at certain places along the Mekong (e.g., Boulikhamxay and Xayaboury provinces), whereas smaller fish occur near the riverbank, in particular around flooded/submerged shrubs.

Information was not received on spawning habits of this species, apart from egg-bearing upstream migrating fish reported by Xayaboury. Previous work under the aegis of the Department of Fisheries in Thailand concluded that the spawning season is July/August, that Cyclocheilichthys enoplos is a total spawner, and that both eggs and larvae are pelagic.

Hypothesis:
Cyclocheilichthys enoplos spawns during the early flood season in the main river, and eggs and larvae drift downstream and out into flooded areas or stagnant, shallow segments of the mainstream. Juveniles and adults also move out into the flood plains during the flood season. When the water begins to recede at the end of the flood season, the fish migrate back into rivers where they start a non-reproductive upstream dispersal migration.

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