Thursday, December 29, 2016

Camera traps & forest islands

When I was born in 1985, the area of western Borneo where I now live was mostly covered in oldgrowth rainforest.  But the past three decades have seen rapid changes.  Our town of Sukadana now has a booming frontier atmosphere.  Swaths of mangrove forest disappear to make way for housing developments, canals and piers.  Forested hillsides are replaced by banana gardens.  New roads pop up almost overnight.  And nearly every day brings the sound of chainsaws in the distance.

Uncontrolled development is not unique to Borneo, but is happening across the country’s thousands of islands.  Indonesia suffers from the highest deforestation rate on the planet.  The islands west of Papua—which make up the vast majority of the country’s land area—have already lost over 70% of their vegetation.  At the same time, Indonesia is a competitor for the most biodiverse country on earth—only Brazil is known to harbor more native species.  By ranking at or near the top in both wildlife richness and environmental degradation, Indonesia is deep in the trenches of the global conservation struggle.

To support our conservation activities, we have tentatively mapped landscape changes around Gunung Palung National Park from 1989 to 2016.  The results are sobering.  In just three decades the park has gone from being a small chunk of a much larger forest to a beleaguered island of natural habitat in a sea of farmland.

The landscape around Gunung Palung National Park (outlined in black in top left), has been decimated over the past three decades.  Dark and light green show oldgrowth and secondary rainforests, and blue shows mangrove forests.  All other colors are some type of land clearing for human purposes.  The area of palm oil plantations in particular (magenta) has exploded over the past five years. (Maps courtesy of Ihsan Fawzi)

The chainsaws don’t stop at the park boundaries.  Every year more of the national park is illegally cleared for timber and farmland.  That’s where we come in.  Our organization tries to slow deforestation in the park using a four-pronged approach.  1) We monitor illegal logging activity and provide financial incentives to communities that halt deforestation.  2) We assist illegal loggers to transition to less destructive employment, and train farmers to become more productive on land that’s already cleared.  3) We teach communities and local schools about the importance of conservation.  And 4) we try to restore cleared areas to natural forest.

Our reforestation sites are small (totaling somewhere around 50 hectares, or 125 acres) and still young.  The first trees we planted are now only seven years old.   And while these budding landscapes are a vast improvement over farm fields and freshly burned landscapes, it will be decades before they revert to fully functional forest.  There are, however, some early signs of success.

Camera traps have captured photos of dozens of native species moving through or occupying our reforestation sites.  Among mammals, for example, we’ve photographed Bornean bearded pigs (Sus barbatus), leopard cats (Prionailurus bengalensis), Malay civets (Viverra tangalunga), short-tailed mongooses (Herpestes brachyurus), lesser mouse-deer (Tragulus kanchil), a Malayan sun bear (Helarctos malayanus), a Horsfield’s tarsier (Cephalopachus bancanus), Bornean orangutans (Pongo pygmaeus), and several others.  All of these on land that just a few years ago was scorched open space.

Bearded pigs survive relatively well around humans and are our most commonly photographed wildlife species

Malay civets, also good at tolerating humans, are often photographed at night


The tiny lesser mouse-deer is less common

We’ve also seen a sun bear…

…and a Horsfield’s tarsier…

…and a couple orangutans (camera trap photos courtesy of Fransiskus Xaverius)

Mammals, however, are just a tiny part of the forest.  In the next year or so we’ll try to find out if native ants and other insects are returning to the new forests, as well as birds and trees.  The results will help us determine which restoration methods help the forest recover most quickly, and how to scale up our efforts to larger areas.

At the very least we’ll provide just a little more space for Indonesia’s unique natural heritage.

Saturday, December 10, 2016

Reforestation season

It’s the wet season in Borneo.  When I first moved here in October it was unbearably hot and sunny, with only scattered rains.  Now the skies are gray, mist hovers over nearby hills, winds buffet our house, and it rains nearly every day, sometimes in deafening downpours that drown out conversation.  And it’s still unbearably hot.

For many trees the rainy season signals the onset of fruiting.  Months of stored nutrients are channeled into fruit production, in anticipation of good growing weather for seedlings.  Here in western Borneo one fruit towers above the rest.  Durian, the king of fruits, is so valued that naturally occurring durian trees are often left standing as the forest around them is cleared for farming or timber.  Massive durian trees now stand over farms and homesteads, remnants of the ancient forest canopy that occupied those sites just years ago.

Our city of Sukadana has even erected a monument to the durian in the center of town.  In the countryside people risk their lives climbing homemade ladders to harvest the fruits from the dizzyingly tall treetops.  Or they camp out at the base of the trees, scooping up fruits as soon as they fall and being careful not to get clobbered by the giant spiky missiles.  Last week, as I entered Borneo from Malaysia, the customs official at the border wiped a smear of durian slime from his passport stamp before welcoming me back.

Rambutans (from rambut, Malay for hair) are one of many native plants that fruit at the start of the wet season

For us the rainy season is planting time.  My organization manages a few reforestation sites within Gunung Palung National Park.  We target patches of the landscape that have been cleared by loggers, farmers, or fires, and try to restore them to natural forest.  The onset of wet weather means a lower threat from fires and better conditions for seedlings.

Our pilot reforestation site is a hilly area that had been clearcut by loggers and then burned repeatedly by fires sweeping in from nearby farms and plantations.  The cleared areas were colonized by alang-alang grass (Imperata cylindrica), bracken ferns (Pteridium caudatum), and invasive acacia trees (Acacia mangium).  The long grass encourages further fires and the bracken ferns release toxins into the soil that impede the survival of young trees.  Without positive intervention to undo some of the damage, these fire-prone barrens stand little chance of recovering.

Our reforestation site is covered by burnt logs, relicts from wasteful loggers who cut down every tree, even those that weren’t harvestable, and the forest fires that followed

Some of the cut trees were centuries old and 3-4 meters in diameter, as demonstrated by one of our volunteers

It takes thousands of years to create oldgrowth forest.  There’s no way for humans to mimic the process.  We can jump start it, however, and provide protection for natural processes to go unhindered.  Starting in 2009, our organization has replanted a few hectares with native rainforest seedlings every year.  We collect seeds and seedlings from remaining forests in the park, rear them to a size where they are likely to survive, and then transplant them to the reforestation site.

Relying on an expert staff of local foresters with experience all over Borneo, we plant native seedlings on degraded areas within the national park

For the most exposed and hottest sites, we often plant fast-growing legumes—mostly jengkol (Archidendron pauciflorum) and petai (Parkia speciosa)—as pioneer species.  We also plant native fruits like mangoes (Mangifera sp.), jambu (Syzygium sp.) and breadfruits (Artocarpus sp.), plus any other native species we can get to survive.  Our most prized seedlings, however, are several species of dipterocarps—a family of giant trees that includes the tallest tropical species in the world.

Dipterocarps usually dominate the canopy in oldgrowth Bornean forests.  Collecting seeds is difficult, however, because the trees only fruit during mast events that occur once every few years.  Nevertheless, we’ve managed to rear a few species of meranti (Shorea sp.).  As mature forest specialists, meranti seedlings often need shade to survive.  So we plant them inside groves of the invasive acacias.  Eventually, the natives will tower over and outcompete the acacias, or we’ll remove the acacias ourselves once the natives have formed a canopy of their own.

Unplanted areas (on the left) are still covered in bracken fern, alang-alang grass, and acacias, whereas the newly-planted plot (right) will soon be covered with native rainforest trees

New seedlings are dwarfed by the charred remains of the site’s original trees, but may one day form an oldgrowth forest.  Once the native trees are tall enough to form their own canopy, the acacias in the background will either be outcompeted or removed by hand.

There are occasional setbacks.  In 2013 a fire escaped from nearby farmland and burnt most of the site, undoing years of effort.  We revised our fire control measures and the planting continued.

Despite setbacks from fires, much of our reforestation site is now covered in young secondary forest

We also haven’t had much success cultivating one of our rarest trees—Bornean ironwood (Eusideroxylon zwageri).  Ironwood is one of the world’s most durable woods, making it a prized timber tree and a cultural symbol for the people of Borneo.  But its durability comes from extremely slow growth.  It takes decades for an ironwood tree to grow a single meter.  They can live for over a thousand years, and those centuries or millennia of tiny incremental growth result in extremely high wood density.  Unfortunately, the combination of high timber value and slow growth means that ironwood has been wiped out from most areas.  While I have seen plenty of ironwood stumps, I have yet to see a full grown individual.

Full-grown Bornean ironwood trees are rare today, but young saplings sometimes sprout from cut trunks

The good news is that Bornean ironwood, if left alone, can resprout from the roots of cut trees.  We have two such individuals at our site, spindly saplings growing straight up from the sides of massive stumps.  Centuries from now ironwood forests may once again be a prominent feature of the landscape.

Until then, we’ll keep planting.

Saturday, December 3, 2016

From Java to Borneo

In preparation for our work in Borneo, Sara and I spent the past month studying the Indonesian language.  We’ve been living in Jogjakarta, on the island of Java, about 450 miles south of our home in Borneo.

When I talk about conservation issues in Indonesia, I usually start with Java.  With a population of around 140 million people, Java is the most heavily populated island on the planet.  It has about the same land area as North Carolina but with fourteen times as many people.  Jakarta—Indonesia’s capital and the world’s second largest city—alone contains over 30 million people in its immediate area.  That’s more than the entire population of Texas, or the combined census populations of the fourteen largest cities in the United States.  All in one massive metropolis.  Needless to say, there is not much room for nature here.

Java’s remaining forests are mostly limited to the steep sides of tall volcanoes.  Almost all other parts of the landscape are devoted to human use.  Crops are planted right up to the edges of rivers and over the spines of ridges, leaving few corridors of natural vegetation.  The vast majority of Java’s native species are now divvied up into isolated populations holding on in pockets of rainforest, unable to cross the expanses of farmland to move from one to another.  Many of Java’s largest species, like elephants and tigers, have already been wiped out.  The world’s last population of Javan rhinoceros, the most endangered of the five rhino species, persists in a single national park at the island’s western tip.

Java’s remaining forests—seen here as dark green dots—are limited to a string of volcanoes running west to east along the island’s spine.  The light green areas dominating the rest of the island are farms or plantations, and gray blotches are cities.  The ashy smear near the northwest tip is Jakarta, the second largest city on earth.

These issues—overpopulation, intense human use, and habitat destruction and fragmentation from farming—aren’t unique to Java.  They’re the primary conservation issues in Indonesia’s other islands and throughout the world.  But as an extreme example, Java illustrates what happens when those processes go unchecked.

Today many of Java’s remaining forests are protected as small, but vitally important, national parks.  Those scattered conservation areas are the last stronghold for the island’s natural heritage, and the key to its the future.  Decades or centuries down the road, as the human population declines to healthier levels and the economy becomes less agricultural and extractive, the hope is that forests and their native species will expand out of their volcanic strongholds and reclaim other areas of the island.

In Borneo, meanwhile, our organization works to ensure that national parks serve as similar refuges for this island’s biodiversity.  We also try to prevent the same excesses that characterize Java from occurring here.  By reforesting degraded areas, mitigating conflicts between humans and natural ecosystems, and developing alternative livelihoods for the region’s poorest communities, we hope to reduce human impacts on the landscape.

Yesterday Sara and I, now armed with a solid understanding of the Indonesian language, returned to Borneo to take up this challenge.  In a fitting start to this chapter of our life, we found that our house had been occupied by some wildlife of its own.  During our month away, vines had taken over our deck and outdoor kitchen, alang-alang grass (Imperata cylindrica) had grown tall in our front yard, and a colony of spiny golden ants (Polyrhachis sp.) had made a nest in between our front door and its frame.

In our own conflict with nature, a colony of beautiful spiny golden ants took up residence in our front door…

…and vines had colonized our back deck from the garden behind the house.

As far as I’m concerned the vines can stay, and I may replace the grass by planting more trees, but the ants had to go.  They fled with their eggs and larvae soon after we opened the door and disturbed them.  Then I carried Sara over the threshold of our first home and we set to work.

It’s going to be an interesting year.