Explorations of an Ecologist

Monday, 29 July 2019

Borneo 2018: Part 10 (Danum Valley)

Part 1: Fly to Borneo, Kota Kinabalu (September 30 - October 2, 2018)
Part 2: Kota Kinabalu to Mount Kinabalu (October 3, 2018)
Part 3: Full day at Mount Kinabalu (October 4, 2018)
Part 4: Mount Kinabalu to Sepilok (October 5, 2018)
Part 5: Sepilok (October 6, 2018)
Part 6: Kinabatangan River (October 6-7, 2018)
Part 7: Kinabatangan River, Gomantong Caves (October 7-8, 2018)
Part 8: Tabin Wildlife Reserve (October 8-9, 2018)
Part 9: Tabin Wildlife Reserve (October 9-10, 2018)
Part 10: Danum Valley (October 11-12, 2018)
Part 11: Danum Valley (October 13-14, 2018)

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October 11, 2018

Our time in the Danum Valley provided some of the best memories of our 2017 tour and I was excited to return. Approximately 438 square kilometres of untouched dipterocarp primary forest is protected here and it is one of the most biologically diverse locations in Borneo. Surrounding the primary forest is managed forest which includes teak plantations interspersed with intact forest.

Danum Valley Conservation Area, Sabah, Malaysia

The Borneo Rainforest Lodge is a world-class ecolodge located just within the boundary of the primary forest on the shores of the Danum River. The lodging is incredible, the food is prepared by expert chefs, the guides are some of the best in Borneo and the setting is perfect. Like with our visit to Tabin, we had three nights scheduled here to allow us to maximize the experience.

October 11 was mostly a day spent in transit as we made our way from Tabin to the Danum Valley. The last hour or so of our drive was on a rough gravel road that took us deep into the Danum Valley, leaving behind the towns, agriculture and plantations. As we passed into the primary forest we came upon the entrance drive to the Borneo Rainforest Lodge, and soon we were sipping on welcome drinks while enjoying hot towels to freshen up. What luxury!

Borneo Rainforest Lodge - Danum Valley Conservation Area, Sabah, Malaysia

Finsch's Bulbul - Danum Valley Conservation Area, Sabah, Malaysia

But while the lodge is incredible we were here for the wildlife. We met our guides who would be accompanying us for all our excursions here, Adzil and Ali, and went over the plan for the next few days.

Adzil (left) and Ali - Danum Valley Conservation Area, Sabah, Malaysia

That afternoon we went for a walk down the main entrance road, flanked on all sides by majestic trees that rose to incredible heights beside the dirt road. The sky was overcast and the air was a little misty so walking along the road was a good call given what limited visibility would be present deep in the forest.

Danum Valley Conservation Area, Sabah, Malaysia

One of the first species we looked at was a female Bornean Orangutan, mostly obscured by branches and high up in a tree not far from the lodge. Not a bad way to start!

While walking up the road, Adzil spotted a suspicious lump high up on a roadside tree that upon closer inspection revealed itself as a White-fronted Falconlet! This species is the world's smallest falcon and a Sabah endemic as well. I was getting worried that we would miss this species on the tour since in 2017 our only sightings were along the Kinabatangan River.

White-fronted Falconlet - Danum Valley Conservation Area, Sabah, Malaysia

But the falconlet was temporarily forgotten when Adzil and I heard some distant vocalizations that could only be one thing - Bornean Bristleheads! We frantically searched for the culprits and spotted them - a roving flock far from the road in the tops of some trees. Luckily we had scopes with us, and soon everyone in our group was able to see them! The Bornean Bristlehead is probably the #1 iconic bird of Borneo. It is the only member of its family (Pityriasidae), endemic to Borneo, and unique looking with a crazy call. Bornean Bristleheads travel in small family groups high in the canopy of lowland forests and can be a tricky species to find at times. My photos are definitely lacking, given the conditions, bu we were thrilled to encounter the group! Traveling with the bristleheads were a few Bornean Black Magpies as well, yet another endemic species.

Bornean Bristlehead - Danum Valley Conservation Area, Sabah, Malaysia

We walked back to the lodge, thrilled with our successful outing. Adzil and Ali were happy as well since some of the pressure had been taken off!

Exploring the entrance road - Danum Valley Conservation Area, Sabah, Malaysia

That evening we ventured out on foot for a couple of hours to see what sorts of nocturnal life we could find.

Bornean Forest Dragon - Danum Valley Conservation Area, Sabah, Malaysia

Nighthikes are probably my second favourite activity in the tropics, after birding mixed-species flocks, of course. In Borneo the nighthiking can be particularly incredible with massive stick insects and centipedes, an abundance of lizards, and the potential for some really unique mammals among other things. Right away we began spotting Bornean Forest Dragons roosting on thin branches in the understorey.

Bornean Forest Dragon - Danum Valley Conservation Area, Sabah, Malaysia

The invertebrates are spectacular here, and you never know what you will come across!

Tanaecia sp. - Danum Valley Conservation Area, Sabah, Malaysia

Haaniella sp. - Danum Valley Conservation Area, Sabah, Malaysia

Giant Centipede (Scolopendra sp.) - Danum Valley Conservation Area, Sabah, Malaysia

Unidentified vinegaroon - Danum Valley Conservation Area, Sabah, Malaysia

Unidentified stick insect - Danum Valley Conservation Area, Sabah, Malaysia

These lanternbugs were a first to me! Unfortunately they were a little too high up for good photos.

Pyrops whiteheadi - Danum Valley Conservation Area, Sabah, Malaysia

Near the end of the night we came across this snake known as a Triangle Keelback hunting treefrogs near a small dug pond along the main road. This snake species reminds me of Nerodia (water snakes) from back home.

Triangle Keelback - Danum Valley Conservation Area, Sabah, Malaysia

October 13, 2018

One of the main features of the Bornean Rainforest Lodge is the presence of a long canopy walkway found on their property. Unfortunately one of the trees holding up part of the canopy had been struck by lightning, rendering about half of the walkway out of order. Fortunately the other half was accessible and after an early breakfast we walked down the road to spend some time in the canopy.

Borneo Rainforest Lodge canopy walkway (photo taken during 2017 tour)

The birding was a little slow at times from the walkway but with patience some new species began appearing: Dark-throated Oriole, Red-throated Barbet, Lesser Cuckooshrike, Whiskered Treeswift. Several Bornean Black Magpies flew in briefly as well. But easily the highlight for us was a Storm's Stork that one of the guides spotted high overhead. I was further back with a few others and heard yelling (Look up!!!); we got on the bird for about ten seconds before it was out of sight. While the views left something to be desired it was much better than nothing. For such a rare bird globally, it seemed extremely unusual to have one in the Danum Valley. I mentioned the sighting to one of the local guides (Azmil) that I knew from 2017 and he was quite excited with the find. He had only seen a couple of individuals previously in the Danum Valley, all high flying individuals like this one.

Storm's Stork - Danum Valley Conservation Area, Sabah, Malaysia

We returned to the lodge by taking one of the forest trails that runs roughly parallel to the road. The morning was becoming quite warm but there were still many things to see. We found another (or the same) small group of Bornean Bristleheads, our first Bronzed Drongo, a Red-bearded Bee-eater (heard only), a Helmeted Hornbill (heard only) and a few other things here and there. I was particularly thrilled to spot a Green Broadbill and I managed to get the rest of the group and the guides on it. Broadbills are probably my favorite Bornean birds and this was the final broadbill for my Borneo list. The photos are terrible; you've been warned...

Green Broadbill - Danum Valley Conservation Area, Sabah, Malaysia

While we enjoyed lunch in the open-air dining area overlooking the Danum River I noticed a small yellow and black bird feeding on a fruiting tree, it was an endemic Yellow-rumped Flowerpecker.

Yellow-rumped Flowerpecker - Danum Valley Conservation Area, Sabah, Malaysia

Flying Dragons (Draco) are some of the best known creatures in Borneo due to their amazing gliding abilities. At least one was perched on a branch beside us while we ate lunch, though we never saw it glide!

Flying Dracon (Draco sp.) - Danum Valley Conservation Area, Sabah, Malaysia

Following a brief siesta we hit the trails in the mid-afternoon. The birding was decent with several species of pittas (Black-crowned Pitta, Blue-headed Pitta) but that is not how the walk will be remembered by most.

It was late in the afternoon and the mist had descended, lowering visibility and causing the incessant calls of the Six O'Clock Cicadas to begin. Suddenly some movement in the understorey caught our attention: it was a huge male Bornean Orangutan, descending from a tree right beside the trail. The next few moments were a bit frantic as myself and the other guides made sure that everyone retreated to a safe distance, but we were given a show as the Orangutan lowered himself to the ground, crossed the path, and went up an adjacent tree. What an experience...

Bornean Orangutan - Danum Valley Conservation Area, Sabah, Malaysia

That evening we completed a night drive up the main entrance road for an hour and a half. While we saw many things, my favorite were the three Thomas's Flying Squirrels that Ali spotlighted high in the trees!

Thomas's Flying Squirrel - Danum Valley Conservation Area, Sabah, Malaysia

A Buffy Fish Owl was also in its usual location at the soccer pitch, a nice way to cap off another great day in Sabah.

Buffy Fish-Owl - Danum Valley Conservation Area, Sabah, Malaysia

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Friday, 26 July 2019

Borneo 2018: Part 9 (Tabin Wildlife Reserve, continued)

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October 9, 2019 (continued)

Before we had even left for our night drive there were cool things to be seen around a pond by the main lodge. This first photo is of a Large Forest Gecko, a species that makes odd vocalizations and is much more frequently heard than seen.

Large Forest Gecko (Gekko smithii) - Tabin Wildlife Reserve, Sabah, Malaysia

Harlequin Tree Frog (Rhacophorus pardalis) - Tabin Wildlife Reserve, Sabah, Malaysia

Large White-lipped Frog (Chalcorana megalonesa) - Tabin Wildlife Reserve, Sabah, Malaysia

The night drive was awesome! While only a couple of Common Palm Civets appeared during the previous evening, we observed several more this evening, both on the roadsides and feeding in oil palms. But the civets were completely forgotten when a small spotted cat appeared at the edge of the oil palm plantation.

Leopard Cat - Tabin Wildlife Reserve, Sabah, Malaysia

It was a Leopard Cat, moving slowly and presumably hunting for rats which feed on the oil palm fruit. Leopard Cats are not much larger than a house cat and like most wild cats they can be secretive and hard to find. However in situations like this, where a forest is adjacent to oil palm, they can apparently be reasonably common.

Another highlight from the drive was the discovery of a Sunda Frogmouth at a known stakeout location. These odd-looking birds look like a cross between a potoo and a nightjar and it was the first one that I had ever seen.

Sunda Frogmouth - Tabin Wildlife Reserve, Sabah, Malaysia

I have no idea how, but Rafael somehow detected this Sunda Colugo hanging from a branch and well off the roadside. The head was tucked in which prevented any eyeshine (the easy way to spot many creatures at night). Colugos are one of the famous "gliders" found in Borneo, a group that includes several squirrels, geckos, frogs, snakes and even ants. While also known as flying lemurs, Colugos are actually much more closely related to primates.

Sunda Colugo - Tabin Wildlife Reserve, Sabah, Malaysia

Upon return to the lodge, one of the travelers noticed this awesome mantid on a railing outside her cabin. Fortunately I was in earshot so I quickly appeared to check it out.

Giant Dead Leaf Mantis (Deroplatys desiccata) - Tabin Wildlife Reserve, Sabah, Malaysia

This species is known as Deroplatys desiccata, the Giant Dead Leaf Mantis.

Giant Dead Leaf Mantis (Deroplatys desiccata) - Tabin Wildlife Reserve, Sabah, Malaysia

October 10, 2018

For our last full morning of exploration Rafael directed the driver of the truck to transport us down a road deep into the reserve. We passed the area of secondary forest that we investigated yesterday and did not stop until the vegetation changed, signalling that we were in more mature forest with a different assortment of species.

Large White-lipped Frog (Chalcorana megalonesa) - Tabin Wildlife Reserve, Sabah, Malaysia

The plan for the morning was to walk the road while the truck would stay a few hundred meters down the road behind us. It would be close enough that it was accessible if someone needed water or anything else, but far enough back that it did not disturb the wildlife. We walked for about three hours until we reached the edge of a partially cleared area, at which point we called it a morning and the truck picked us up.

Rhinoceros Hornbill - Tabin Wildlife Reserve, Sabah, Malaysia

It was an exciting morning to say the least. Mixed flocks were frequent and new birds appeared in our binoculars and through our camera lenses. Asian Fairy-Bluebird. Brush Cuckoo. Olive-backed Woodpecker. Dark-throated Oriole. Plain Sunbird. Charlotte's Bulbul. The hits just kept coming!

Black-and-yellow Broadbill - Tabin Wildlife Reserve, Sabah, Malaysia

Flycatchers were well represented and three of the species were completely new for our group (Bornean Blue, Verditer, and Blue-and-white Flycatchers). Even a few migrant Arctic Warblers were around. At one point a dark shape glided overhead and was quickly identified as a Wrinkled Hornbill before it disappeared.

Chestnut-rumped Babbler - Tabin Wildlife Reserve, Sabah, Malaysia

A Bartlett's Flying Dragon was spotted as it made its way up the side of one of the roadside trees, causing a bit of excitement. Even better, as we watched it suddenly lept from the tree, glided right over our heads, and landed on the other side of the road. Incredible!

Bartlett's Flying Dragon (Draco cornutus) - Tabin Wildlife Reserve, Sabah, Malaysia

We finished our morning walk by listening to the incredible calls of two Helmeted Hornbills, representing our fifth hornbill species of the day already and a nice way to wrap up the morning.

The rains came shortly after lunch and it was late afternoon when we reassembled for another dusk drive.

Chestnut-breasted Malkoha - Tabin Wildlife Reserve, Sabah, Malaysia

Near the start of the drive we stopped on a few occasions to listen for White-crowned Hornbill since they can sometimes be found in the area. We were successful but spotting the bird would be another matter! Fortunately Rafael knew the areas where this species sometimes perches and fifteen minutes later we were looking at one, distantly perched beside a radio tower. We frantically tried to get the group on the bird and were successful, though photos leave a lot to be desired. The White-crowned Hornbill is the most carnivorous of Borneo's hornbills and also likely the rarest. It was the sixth hornbill of the day for us and was the eighth and final hornbill species for us on our trip - a clean sweep!

White-crowned Hornbill - Tabin Wildlife Reserve, Sabah, Malaysia

Crested Serpent-Eagles seem to be the default bird of prey along waterways, roadsides and forest edges in Sabah. We noted this species daily during our tour.

Crested Serpent-Eagle - Tabin Wildlife Reserve, Sabah, Malaysia

Around dusk we lucked out with a few more hornbill sightings. The first was a Wrinkled Hornbill which gave much better views than the individual from the morning, low light levels notwithstanding. We also saw a group of six Bushy-crested Hornbills flying to their roost, our seventh hornbill species in nine hours.

Wrinkled Hornbill - Tabin Wildlife Reserve, Sabah, Malaysia

We stayed out well past dusk as it was our last night at Tabin and we wanted to make the most of it. This proved to be a good decision, as the next photos show...

Banded Civet - Tabin Wildlife Reserve, Sabah, Malaysia

The animal pictured is a Banded Civet which is a poorly known species that is infrequently encountered. It was walking alongside the edge of the road and immediately I knew what it was when our flightlights lit up the distinctive striped pattern on its dorsum. The Banded Civet seems to be a species of primary rainforests where it can apparently be reasonably common. However the population crashes in logged forest and the species can not survive in secondary forest. Banded Civets are usually very shy which adds to their allure. I had longingly looked at this species pages in my mammal field guides on several occasions and so to see one in the flesh was surreal.

Banded Civet - Tabin Wildlife Reserve, Sabah, Malaysia

Amazingly, the Banded Civet stuck around long enough for everyone to have excellent looks and I even managed a few acceptable photos, which was not an easy proposition given the situation.

Banded Civet - Tabin Wildlife Reserve, Sabah, Malaysia

Other mammal highlights included both Red Giant and Black Flying Squirrels, many Common Palm Civet, and a Malay Civet just as we were turning into the lodge driveway.

Malay Civet - Tabin Wildlife Reserve, Sabah, Malaysia

Our time at Tabin was nearly complete as we would be departing early the next morning. But looking back, it is amazing all of the sightings that we had in such a short period of time thanks to Rafael. I can not wait to get back to Tabin in 2020!

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