24 June 2011 1 of 3


MAININA, LAUTÉM DISTRICT, TIMOR-LESTE

 

 

TIMOR-LESTE REPTILE & AMPHIBIAN SURVEY
PHASE V: WHERE THE RIVER VANISHES
(page 1)

Today's outing would take us south to Lospalos and then eastwards, south of Lake Ira Lalaro, to Malahara village where we had arranged to pick up a local guide and a forest guard. From here we would drive as far as possible into the forest at the foot of the Paitxau Mountains and then walk the remainder of the way to the Mainina sinkhole.

A lurking Saltwater crocodile,
Crocodylus porosus, one of 300 in Lake Ira Lalaro
click on image to enlarge

We arrived in Malahara and our attention was drawn to a large adult Saltwater crocodile (Crocodylus porosus) that was lurking off-shore near a group of water buffalos and their calves, surely waiting for one of the youngsters to stray too close to the water's edge. We could not wait to see the result of the stalking as our guide was ready to go with us to the sinkhole.

Several rivers feed into Lake Ira Lalaro, Timor's largest lake, but only one river exits the lake. The Irasequiro River flows east from the lake and vanishes down the Mainina sinkhole beneath the Paitxau Mountains.

Curiously, from here some of the river water runs south into the Timor Sea while the majority turns north underground to empty into the Sunda Sea near Com.

Our plan was to visit the sinkhole and herp in the limestone karst enroute.

The sign for Nino Konis Santana National Park, which includes the Mainina sinkhole.
We parked a little beyond the sign.

The drive from Malahara to the sinkhole proved to be relatively short, and although we negotiated mud-wallows in Low4 we were prevented from going much further by several large treefalls. One of the Troopies also suffered a flat tyre which had to be replaced before we set off to walk.

The climb up and over the karst was short and steep, but it was worthwhile to visit the sinkhole which consisted of a green lake surrounded by forest and rocks. Although the surface was still, deep below in the depths there were open plugholes down which the river was steadily pouring like water emptying out of a bathtub. At a certain time of the year, when water levels are much lower in Lake Ira Lalaro (as we had observed in 2009), this green lake would turn back into a sinkhole with a waterfall in the centre.

Mainina sinkhole, a large green bath with the plug removed.

Trekking back to the vehicles we stopped for an improptu lecture on how rainforest trees require buttresses to support themselves on the thin soil of the jungle floor and to consider likely locations for a night hunt. Top of the list was a limestone cliff which we thought would be good for geckos.