Yellow-headed water monitor (Varanus cumingi)
The yellow-headed water monitor (Varanus cumingi), or Cuming's water monitor, is one of the smallest members of the Varanus salvator group, and one of the most bright-colored and attractive. It inhabits the mangroves and tropical rainforests of the Philippines (endemic species to the Philippines islands), but can also be found in modified habitats of low-to-mid elevations. The population density is quite low.
Adult lizards usually attain a length of about 150 cm. The basic coloration of adults is dark with yellow bands, mostly a yellow head.
Like other monitors, the yellow-headed water monitor (Varanus cumingi) is a diurnal predaceous species. It prefers to prey on fish, but small-scale rodents, lizards, amphibians, arthropods, etc., could be eaten as well. Generally, we have fragmentary information about the biology of these interesting monitors.
The captive breeding of the yellow-headed water monitor (Varanus cumingi) was successful several times but still remains a significant event.
In 2013, we received a pair of yellow-headed water monitors as juveniles. The first breeding in BION took place in 2015.
The enclosure size is 150x100x100cm.
Substrate: bark pieces, leaf litter, and wood scrap (from deciduous trees). The layer thickness is about 8 cm, providing a possibility of scrabbling.
Decoration: a large water container of about 25-30 cm deep with filter is necessarily provided for drinking and swimming. The water temperature is 23 to 26 º C.
Illumination: a full spectrum lamp. The daytime length from April till July is usually 14 hours, and from August till March it is 7 hours.
Temperature and heating: a full spectrum lamp OSRAM 300 W provides 50º C at the basking spot. UV lighting is important for young animals, so we use a UV lamp along with a full spectrum lamp. The temperature at the enclosure is 27-28º C at night and 28-32º C during the daytime.
Diet: adult animals receive rats, mice, fish, pieces of chicken hearts and quail eggs . We feed them twice a week.
Mineral supplements: not required.
Hibernation: a gradual temperature and the day length decrease starts in October. Two weeks of wintering pass with the 24º C temperature and 7 hour day lighting. After the cold period, we gradually return heating and lighting to its summer level. The warm period begins in April.
According to our experience, in captivity, the yellow-headed water monitor (Varanus cumingi) becomes mature at the age of 2.5 years.
The breeding season begins in April, when we start observing mating, and lasts up to July. The male is then quite aggressive, and can even injure the female quite seriously (personal observation)! So, the female needs more shelters during this period.
The first clutch we had in July 2015 with 5 eggs and 4 hatchlings.
Temperature of incubation: 29 – 30º C
Duration of incubation: 200 – 204 days.
Humidity during incubation: 70-90% (a drop of water should appear on the substrate surface (vermiculate) after pressing it).
Hatching of each egg takes over 3 days. Youngs are aggressive, and we keep them separately, in conditions, common to adults’ ones.
Their SV length is about 120 mm, with a total length of 33 cm, their weight is 30-36 g.
We keep young animals in plastic boxes.
Substrate: paper towels.
Humidity: babies need spraying on a daily basis and a water bowl.
Feeding: crickets and rat meat pieces every second day.
Calcium supplement is offered with every feeding.
Till this moment, the only problem with traumatized female took place in our lab during the mating season. The surgery helped to cure the animal.
1.. Koch, André, Gaulke, Maren & Böhme, Wolfgang, 2010, Unravelling the underestimated diversity of Philippine water monitor lizards (Squamata: Varanus salvator complex), with the description of two new species and a new subspecies, Zootaxa 2446, pp. 1-54: 14-16