Thursday, February 23, 2012

Canoeing Rawa Bento Swamp

Photo by Luke Mackin
Wetlands (swamps, marshes, estuaries, etc) are an important part of the landscape of Southeast Asia.  In the past wetlands have been regarded as wastelands, and many of them have been converted into more "productive" uses, like agriculture and aquaculture.  Although ecologists, biologists, and geographers have long understood and studied the unique characteristics of wetlands, it is only in the past couple of decades that the ecological importance of wetlands have been recognized by a wider audience.  This past Sunday I had the opportunity to visit Rawa Bento swamp ("rawa" means "swamp" in Indonesian; "bento" refers to an endemic species of grass found in the area) here in Kerinci district with a couple of friends.  Rawa Bento is about 2000 hectares, with 1100 hectares in Kerinci Seblat National Park.  I was really interested in visiting the swamp because it has become an issue between the regency government and the managers of the park.  The regency wants to drain the swamp and convert it into rice fields.  They even received 35 billion rupiah (about $3.88 million) from the central government for the project.  The project had to be put on hold, though, because the swamp lies within the territory of the park, which is off limits to any kind of development (1).

The Importance of Wetlands

Map of Sumatra's Welands from here.  
Swamps, marshes, and estuaries are generally found in lower reaches of rivers where the topography (shape of the landscape) in gently sloping and where the water moves relatively slowly.  Freshwater swamps, like Rawa Bento, are defined as areas where the land is permanently or temporarily inundated by mineral-rich freshwater.  Freshwater swamps are different from peat swamps (another important type of swamp) because peat swamps are primarily watered by rain, whereas freshwater swamps get rain and river water, and so the soil is very rich.  Freshwater swamps have a lot of important functions; they prevent flooding because they hold water like a sponge.  When it rains a lot the wetland stores water, and when it is dry wetlands slowly release water into streams.  At the same time they provide nutrients from decaying biomass into the streams, which serves as food for fish and other organisms living in the stream.  Many animals that live in habitats outside the wetlands use the wetlands for migration or reproduction as well.

White Throated Kingfisher/Cekaka Beluka
(Halcyon smyrnensis) photo by Luke Mackin
Rawa Bento, though, is unique.  It's not a lowland swamp or an estuary like most of the wetlands in Indonesia.  Rather one of the highest wetland in Indonesia.  In addition, recent research by the Kerinci Birdwatching Club and graduate students from  the State University of Yogyakarta (UNY) has revealed that Rawa Bento is an important stopover for wetland migratory birds, some coming as far as Russia, such as the Wood Sandpiper and the Pacific Black Duck.  There are also a number of endemic species (found only in Rawa Bento).  Rawa Bento acts as a sink for runoff, where the sediment settles out of the water flowing in.  The wetland serves as a filter that the water flowing out of the swamp is cleaner.  The water flowing out can then be used for irrigation and and drinking.  In addition the swamp is a spawning area for fish and is a sanctuary for crabs and freshwater shrimp.  Rawa Bento is also thought to have some regulatory function on the local climate, but research still needs to be done to fully understand the relationship between the swamp and the local atmosphere.

Wetlands in Indonesia (and Southeast Asia in general) face a number of threats.  As I mentioned earlier, wetlands have historically been viewed as areas for conversion and expansion, and large-scale draining of wetlands in Malaysia and Singapore began in the 1930s.  Inland swamps are drained to become agricultural fields or residential areas, whereas coastal wetlands are converted to aquaculture, most notably shrimp farms.  In recent years sea-level rise associated with global warming has been recognized as an additional threat.  Many wetland areas in Indonesia are susceptible to rising seas, as you can see from the map below.
Map from CI:GRASP
A Swamp Adventure...

Don't forget to write!
We left Sungai Penuh a little after 7am.  It takes about an hour to get up to the swamp from where we live, and we wanted to put in early because you have a better opportunity to see wildlife if you are in the water before noon.  When we arrived in Pelompek (the village closest to the put-in point) we chatted a bit with the locals and arranged for a dugout canoe.  My good friend Luke, who provided some of the beautiful photos for this post, brought along a couple of rubber rafts that he wanted to try out.  Luke has a pretty good sense of humor, so I doubt he'll object to a bit of good-natured ribbing, but as he inflated one of the rafts about a dozen children from the village gathered to watch the show.  They'd never seen rubber boats before, and they were pretty curious about what these two foreigners and their Indonesian friend were up to.  After inflating the raft, Luke intrepidly entered the current and was promptly swept away by the creek that runs through the swamp.  To the delight of the gathered children, two locals quickly took a dugout downstream to "rescue" Luke.  We tried a couple of other ideas to make use of the rafts, but eventually the local way of doing things prevailed and we set off in dugout canoes.

After we got underway we paddled upstream for about 2 hours towards a lake.  Since the rainy season is petering out here the water in the lake was pretty low and lots of grass was exposed.  But when it rains the lake swells to several times its dry season size.  Along the way we saw a number of birds as well as a troupe of mitred leaf monkeys ("Simpai" in Indonesian; Presbytis melalophos melalophos).  After a short break we headed back; the trip downstream takes about an hour, so the whole trip is about 3 hours.  The earlier you leave the better, because it tends to rain a bit in the afternoon.  We got thoroughly soaked, and given the elevation (about 1400 meters above sea level) it can get chilly.  But all in all it was a great trip.

If you'd like to visit Rawa Bento, you can arrange a tour including transportation through the Kerinci Birdwatching Club (KBC), which I've mentioned in this blog in the past and will dedicate a full post to next week.  The advantage of going with KBC is that they can tell you all about the wildlife of the swamp as well as its history.  In addition, money earned through activities such as this help KBC fund bird conservation efforts.

Notes

(1)  One interesting aspect of this case is that the regency officials framed the issue to portray the park as an impediment to development, suggesting that the park sabotaged the conversion project.  One wonders why the regency leadership didn't simply make a call to the regency planning office (or even the park) to ask whether the proposed area fell within the park or not.

1 comment:

  1. I thought this article was interesting because it talks of the importance of swamps in general and how unique Rawa Bento swamp was from its location to the distinct birds it receives. Such as the Wood Sand Piper and Pacific Black Duck. I had no idea swamps serves as a buffer from retaining water to prevent flooding and to slowly releasing nutrient rich water into rivers when needed. I think wetlands should be preserved to hold the natural cycle of water flow.

    ReplyDelete