MUSCAT: The Office for Conservation of the Environment, at the Diwan of Royal Court, in association with experts from the Harrison Institute of the UK, supported by the Anglo-Omani Society, recently completed a month-long field trip surveying the small mammals of Dhofar.
Amongst the small mammals are the bats, a group of animals that are often overlooked but are vital to the maintenance of healthy ecosystems throughout the world.
In September the survey team travelled throughout Dhofar in search for bats; from the monsoon woodlands of Jabal Al Qara and Jabal Al Qamar, through the farms of Salalah to the dry wadis of Jabal Samhan and the Nejd.
In the daytime, when the bats sleep, the team searched caves, sinkholes and old buildings while after sunset they set their bat nets close to water, in woodlands and in narrow wadis in the hope of catching these elusive creatures of the night.
The first bat, the team encountered were the fruit bat (Rousettus aegyptiacus), the largest and most common of Oman’s bats. They emerge from their daytime roost, such as caves, just after sunset and with a very sophisticated sense of smell go in search of fruit. These may be wild fruits such as figs or the abundant fruits of the farms around Salalah and elsewhere in Dhofar including mangoes, papaya and coconuts.
The bats may benefit from an abundance of fruit but the fruit trees themselves are dependent on bats for pollination and the spreading of seeds. Thus these bats are beneficial to both wild plants and agricultural crops. The fruit bats may be the largest of the bats but they are extremely gentle when handled correctly.
However, the majority of Dhofar’s bats and 70 per cent of the world’s bats are insectivores and the end of the monsoon (khareef) is a time of plenty for insect eating bats as thousands of insects emerge around sunset. The team caught at least 14 different types (species) of insect eating bat including the spectacular Ghost bat (Otonycteris hemprichii) of which there was just a single record from 1977 when it was found in Wadi Ayun.
With its huge ears and light body colour it is a very distinctive bat that lives only in the drier areas of Dhofar, particularly the Nejd, where it was found in the northward flowing wadis such as Wadi Arah. It feeds on many different insects including scorpions, providing a vital service to the desert ecosystem.
At first sight many small bats may seem to be the same but there are many different families of bats that to the experienced eye can easily be distinguished. One family of bats has a distinctive horseshoe-shaped nose and are thus known as horseshoe bats. One example is Geoffroy’s horseshoe bat (Rhinolophus clivosus) that is found in Dhofar but not in northern Oman.
The smallest of the bats encountered in Dhofar were the Pipistrelle bats that weigh about 5 grams and are the size of a human thumb. The recently discovered Pipistrellus dhofarensis was the most commonly encountered; a species that is only found in Dhofar and across the border in eastern Yemen. Like most bats this species has very poor eyesight and uses echolocation, similar to sonar, to fly and to hunt for insects in the dark. As they fly they make calls and they can tell how far away something is by how long it takes for the echo of the call to return to them. Just as radio stations broadcast at different frequencies bat species call at different frequencies and these frequencies can be listened to with a bat detector to determine which species is calling.
Bats are wonderfully beneficial creatures but are among the most misunderstood of animals, often feared as sinister and unclean creatures of the night. Far from being our enemy, bats are our friends. Many plants rely on them to pollinate their flowers, others to spread their seeds. They are also pest controllers and eat insects that are harmful to agricultural crops and to man. Ultimately bats are a good indicator of the health of natural habitats.
Although there are more than 25 species of bat in Oman they have remained largely under the radar of the conservation community. It is hoped that this survey, that included the training of local rangers, will mark the beginning of the conservation of this group of mammals that is found throughout the Sultanate and performs essential services to man and nature.