No abstract

Water monitors (Varanus salvator) in Dusit Zoo range, Bangkok, Thailand, were observed from July to October 2015. A total of 90 individuals were captured, measured for SVL, sexed, and marked on the right axilla. More females (n = 70) were captured than males (n = 20), a sex ratio of 3.5:1. There was no significant difference in size between genders. Daily activities included foraging twice a day (mostly for fishes) in the morning (0600-0800 h) and afternoon (1500-1700 h), basking 5-7 hours after a morning meal, floating in the lake after noon, and randomly performing some sexual behaviors were displayed routinely among the study. In addition, this population frequently displayed a predating natural prey, especially fishes, in the morning, rather than opportunistic scavenging on human food and fish-leaving leftover which performed among daytime.

From July to October 2015, a study was conducted on the water monitors (Varanus salvator macromaculatus) at Dusit Zoo in Bangkok, Thailand. A total of 90 monitors were captured, measured for SVL, sexed, and marked on the right axilla. The captured monitors included 70 females and 20 males, resulting in a sex ratio of 3.5:1. Body size did not differ significantly between genders. The monitors exhibited bimodal diurnal activity, with a focus on fish hunting in the morning (06:00–08:00 h) and scavenging for fish leftovers in the afternoon (15:00–17:00 h). After the monitor lizards hunted for prey in the morning, they spent 5–7 hours basking and floating in the lake during the afternoon. Sexual behaviors were also occasionally observed. The monitors displayed frequent predatory behavior towards natural prey, especially fish, in the morning, as opposed to opportunistically scavenging on tourist food and fish leftovers observed throughout the day.