Nature's wealth

PUBLISHED : Thursday, 19 May, 2011, 12:00am
UPDATED : Thursday, 19 May, 2011, 12:00am


By this time of the year, Mai Po's black-faced spoonbills are off to the north. Yet the wetland is anything but deserted and silent.

As the sun sinks behind the horizon, the landscape comes alive with sound as choruses of frogs, crickets and bugs burst into song. Summer is a busy time at Mai Po Nature Reserve in Deep Bay. It's breeding season for insects, bats, frogs, crabs and the mysterious leopard cats.

The 380-hectare park is registered as a 'Wetland of International Importance' under the Ramsar Convention.

With torches at the ready, guide Jerry Wong Tak-yan led Young Post into the night for a visit to Mai Po's nocturnal residents.

Encounter 1: Bats

One way to spot these creepy creatures is to keep your eyes on the sky. There they are - black shadows erratically flitting through the air, unlike birds, which tend to fly in straight lines.

You can also switch on a bat detector. Every species relies on unique high-frequency echoes to navigate their way as they search for insects. The human ear cannot pick up bat calls, but the device can turn them into audible beeps.

Mai Po's most commonly found species is the Japanese house bat. For a closer look, try one of the three wooden bat boxes just outside the education centre.

Encounter 2: Fireflies

To the left of the education centre, dozens of fireflies glow on and off over a freshwater pond, twinkling like little stars. They shine in many colours from white to pale-red to green.

'Mai Po is the largest firefly reproduction ground in the Pearl Delta,' Wong says.

For an insect that lives for just a week, fireflies may look fragile. They aren't. They can even feed on snails and slugs by injecting strong digestive juices into their prey. Then they suck up the dissolved flesh, leaving an empty shell.

Encounter 3: Snakes

There are 12 native snakes at Mai Po. Non-poisonous checkered keelbacks are the most common, while mangrove water snake are found only in the reserve and Tai O.

These slithery residents are most active in summer when they are out and about looking for a mate. Young Post came upon two keelbacks - one slithering on a tree and the other swimming in a pond.

Encounter 4: Frogs

In no way was that second snake going for a dip by chance. The pond and its environs teem with myriad frogs in a mini-ecosystem. Gunther's frog, black frog, brown tree frog, Asiatic painted frog - they all gather there in the food-rich waters.

Wong says he once saw eight lovesick male frogs circling a single female - all singing to win her over.

Encounter 5: Damselflies and dragonflies

Rain showers bring slender dragonflies and damselflies out in droves. Dragonflies are typically larger than damsels. Their wings lie flat like those of airplanes, while damsels fold theirs over their backs. Both insects spend their childhood underwater. It is not until they are two-months-old that they will climb out into the air. Young Post witnessed four moulting, breaking free from their skeletons and standing on a leaf where they wait for their wings to expand for a whole new life of flight.

The WWF offers guided tours on weekends until the end of August