Throughout Borneo, Sambar Deer Cervus unicolor are regarded as serous pests of agricultural crops.
These crops include rice (padi), maize (jagung), tapioca (ubi kayu) and rubber plantations (getah). Sambar Deer are serious pests of many trees grown in reforestation projects. Sambar deer have iron clad stomachs and powerful livers that can detoxify plant latex and plant poisons.
Sambar are also a serious pests of young fig saplings and they are probably an important driver of strangling fig evolution. It is well known that some fig species such as Ficus callosa are common around towns but rare in forested areas. The reason is probably that deer have been hunted out near towns.
Photos and information provided by Shavez Cheema and Chun Xing WONG of 1Stop Borneo Wildlife.
Soon after the Maliau Studies Center first opened, Sambar deer began gazing on the grassy padang surrounding the buildings. The reason was probably two fold. Firstly deer were attracted by the young grass growing on the padang and secondly they felt safe from Clouded Leopards which stayed away from the new buildings.
ABOVE. Twin Ficus dubia figs growing on a stump at the Maliau Basin Study Center in central Sabah. At dusk Sambar Deer arrive to graze on the grass and browse the delicious fig leaves. Note the browse line which defines the level of the lower branches of the fig. The browse line is the highest level the deer can easily reach. If the fig is fruiting then the deer will also eat the fallen figs.
Until a couple of years ago Clouded Leopards were rarely seen at Maliau. Camera trapping showed that they were present but very shy. In recent years Clouded Leopards at Maliau have become much bolder and are increasingly seen along the roads at Maliau at night. Clouded Leopards are the main predator of Sambar Deer in Borneo. Due to the recent collapse of the wild pig population in Borneo (following the introduction of African Swine Fever) it is likely that male Clouded Leopards are now concentrating on Sambar Deer as prey. Note that only male Clouded Leopards are big enough to kill Sambar deer. Female Clouded Leopards are only half the weight of a male and would find it difficult to kill an adult Sambar.
This has very interesting implications for the enrichment planting of figs around the Maliau Basin Study Center. Normally these young fig saplings would be quickly predated by Sambar Deer. However bold and hungry Clouded Leopards are likely to target the Sambar deer that gather on the padang at the Study Center. This could have great benefits for young figs planted along the forest edge where deer feel unsafe.