Birds, bats and a tembusu sprig

posted in: Feeding-plants, Interspecific | 1

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Early one morning I found a fresh sprig of tembusu (Fagraea fragrans) with ripe berries still attached, on the top of my car’s boot (left). The car was parked under the porch with the rear end jutting out near to where one of my ceram palms (Rhopaloblaste ceramica) grow.

The palms are a favourite perch for many species of birds and any one of the fruit eating birds could have dropped the tembusu sprig. But do birds normally pick a fruiting sprig, rather than picking the fruits individually?

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On the other hand the porch is a favourite roost of the Lesser Short-nosed Fruit Bat (Cynopterus brachyotis) (right).

The question posed is, was it a bird or a bat that deposited the tembusu sprig on my car? The consensus among the few who are familiar with bats is that it was a bat that was responsible.

Here are the reasons for suggesting bat:

Bats normally bring fruits back to their feeding roost to eat, especially large fruits. With small fruits, the bat usually eat them on the spot. In the case of tembusu whose fruits are small, it is possible that they may be eaten around the tree. However, to collect a sprig with more than a few fruits back to eat saves time and energy.

And are there instances of birds breaking off a sprig of tembusu bearing a few berries to be eaten somewhere else? Have there been any observations of such behaviour?

Is there any evidence of bats breaking off small branches for whatever reasons? Here, I can confidently say that it does happen.

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My porch is a regular roosting site of these bats (above). At first a few came, leaving droppings on the ground below. Then one day a horde of them made themselves comfortable under the porch. And the mess thay left behind every morning could one day be mined for guano. So our helper chased them away. But a few still continue to come. And one or two roosted in the small Dracaena “Song of India” (Dracaena reflexa) tree, taking shelter under my porch whenever it rains (left top).

When these bats first started using the tree as a roost, I found a sprig of the dracaena on the ground below together with a number of fresh leaves (left bottom). Apparently the bats ripped them off the branch to clear a space to roost.

So bats do rip small branches off trees. And the tembusu sprig on my car most probably was left there by a bat.

We would love to hear from birders who have observed birds plucking sprigs bearing fruits to be eaten elsewhere. But then, do birders bother about bats?

YC Wee, Vilma D’Rozario, Yap Kim Fatt & Angie Ng
Singapore
October 2007
(Images by YC Wee)

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One Response

  1. […] A colony of Common Fruit Bats (Cynopterus brachyotis) had been roosting in my porch since 2006 LINK. […]

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