Wetlands International surveys II

It's been a while since my last update. I have been rather busy with work and also was in Europe for 10 days, part work and part meeting up with friends. It felt good to be back in Europe for a while, it's hard to beat enjoying good food with old friends on a long summer evening.

The second dedicated bird surveys for the Wetlands International project started when I was away last week (for an introduction to the WI project, see a previous post: wetlands international survey). WI is doing an excellent job pulling in the experts: after Dennis Yong, this time Dave Bakewell is leading the bird surveys. Dave is one of the foremost bird experts in the region and hardly needs an introduction. If you have never visited his weblog than please do so at dig deep, a great read and teeming with useful information on bird identification.

Again I have again been lucky to be invited to help out. Last Thursday I joined one of the surveys, which was an excellent way to rid myself quickly of the jet lag. We met up in the early morning to explore the more remote areas of peat swamp and kerangas forests that are typical of the lower Belait district. On the way we saw a lesser adjutant, a good omen! At our first locality we had good, though slightly distant, views of a male scarlet-breasted flowerpecker. This is not an easy bird to find and I am very happy that I got a few shots of this splendid little bird!

Crimson-breasted flowerpecker (Prionochilus thoracicus).

There was plenty of other bird activity, though most was out of reach of my camera. Rare birds elsewhere, cinnamon-headed green pigeons are a relatively common sight in the open areas and we spotted several smaller flocks. A group of thick-billed green pigeons had joined the cinnamon-headeds in the tree pictured below, before flying of:

Cinnamon-headed green pigeons (Treron fulvicollis) and
 Thick-billed green pigeons (Treron curvirostra).

With Angus, Dave and Kolbjorn.

When we moved to the next locality we soon heard a species that has eluded me for the past 3 years: the hook-billed bulbul! This is a peat swamp specialist, and there is no surprise that it is found here. Pristine peat swamp forest is getting increasingly scarce on Borneo and with the rapid disappearance of suitable habitat this species is listed as threatened (vulnerable) by IUCN.

Hook-billed bulbul (Setornis criniger). 

And so I finally added this long awaited lifer to my Bruneian list. In the below picture the distinctive white tail tips can clearly be seen - most of the head is however well hidden behind a branch and I will definitely need to try for better photographs in the future!

Hook-billed bulbul (Setornis criniger).

We continued again at dusk with the aim to get Dave good pictures of the Bonaparte's nightjar. Around the Badas area literally thousands(!) of flying foxes can be observed as they fly over to their preferred fruiting spots. The flying fox is the largest flying mammal and it is a very surreal sight to see so many big bats flying overhead in an almost continuous stream, it delivers a vague sense of being part of the latest vampire movie.
These mass wanderings seem a recurring phenomenon, as I had witnessed it before in 2010 and I suspect they are related to temporary localized fruiting periods. With the dusk setting in I failed to capture a good impression of the full scale of the bats passing by, but I did get some shots of individuals flying over.

Large flying fox (Pteropus vampyrus).

Batman!

We did hear and see the nightjar, but the bird couldn't be tempted to show itself well enough for any pictures. While waiting for the nightjar a colugo soared by overhead, landing not too far away from us. These animals can truly glide, I estimate that this individual covered at least a 100 meters with a single jump/glide/flight.

Sunda flying lemur or Colugo (Galeopterus variegatus).
Note the little peeping Tom.

These trips into the more remote parts of the lower Belait seem to imply that some of the species typically associated with nutrient-deficient soil forests are especially sensitive to disturbance. While I have recorded some great birds in the past 3 years along the Kuala Balai road I have never seen hook-billed bulbul and scarlet-breasted flowerpecker there and only very rarely encounter cinnamon-headed green pigeons: one could hypothesize that the road and related activity has a clear negative effect on the presence of the aforementioned species. With the ever expanding human encroachment on nature the efforts of Wetlands International will be an important step towards building a sustainable future for the lower Belait forests. I am anxiously looking forward to the findings and recommendations of this project.

Folkert, 21/06/2013

Wetlands International surveys

If you're expecting loads of nice bird pictures, this post may be a little disappointing... There has however been some great birding in Brunei last week, even though the total number of birds seen is rather low and the photographic evidence even more meager. But what a week!

In an earlier post I mentioned that Wetlands International just started with an 18 month project for the lower Belait district. This is a collaborative effort between Brunei Shell Petroleum and Wetlands International. There are several objectives to this project that foremost aim at a sustainable future for the fragile peat swamp forests of Brunei's lower Belait district. For more information please see this link.

The Biodiversity surveys form an important part of the project and since last week some globally recognized experts are surveying the area, including Dennis Yong. Dennis is one of the foremost Malaysian naturalists and his skills with picking up and identifying bird call are truly impressive - he seems to not only identify almost every single call, but is also able to mimic most calls directly from memory. And he is a really nice guy!

I feel very fortunate to also have been given the opportunity to help out. This week I have been assisting in the field on a couple of occasions, and especially Saturday was very memorable: the first time I have taken a boat ride up river from the Kuala Balai road to venture a deeper into the peat swamp forest. Saturday early morning we (Kolbjorn, Dennis, Merijn and myself) had arranged to meet up at the end of the Kuala Balai road. On our way over Kolbjorn and I had some splendid views of a ruddy kingfisher. We dipped however massively on the clouded leopard(!) that was seen by Dennis and Merijn next to the road, and only 10 minutes after we had past the exact same spot.
Our upstream destination was a little rickety rail track leading to a small logging concession, only accessible from the river. The rail track runs through some good peat swamp forest. On the river we spotted a chestnut-winged cuckoo (Clamator coromandus), which provided some good views. This is an uncommon/rare winter visitor to Borneo and was a lifer for me.

We arrived at the start of the trail/track around 08:00 and there was enough activity going on. We heard plenty, including 5 different hornbill species, good views were however few and far between. The most enticing call was surely the hook-billed bulbul. Attempts to call it in were unfortunately unsuccessful, and I hope to have another opportunity soon. Kolbjorn soon spotted a scarlet-breasted flowerpecker (Dicaeum thoracicus), a male, foraging in front of us. Another lifer for me and what a stunner! From habitat description the presence of this bird is not unexpected; to actually see one is an entirely different matter!

Besides the birds, we did also see some other forest life. This sambar deer was seen next to the track before it shot off with an ear-piercing alarm call.

Sambar deer (Rusa unicolor).

This giant squirrel observed us from a tree and then made for the deeper forest, possibly showcasing how it's cousins, the flying squirrels, evolved with some huge jumps. 

Cream-coloured giant squirrel (Ratufa affinis).

There were also plenty of cool insects around. This Kytadid does an excellent job in mimicking a leaf.

Kytadid sp.

On the way back on the river we noticed a group of 5 straw-headed bulbuls. I had seen these birds previously in Danum and on the river upstream from Limbang, though never before in Brunei. The straw-headed bulbul is listed as vulnerable, mainly because of trapping for the cage-bird trade. To see it in Brunei is a good record. The 3 pictures I got are absolutely useless - but since this blog is mostly about the Brunei birding I decided to stay within the theme and include one anyway:

Straw-headed bulbul (Pycnonotus zeylanicus)

A final noteworthy record is the Bonaparte's nightjar (Caprimulgus concretus), also listed as vulnerable by IUCN. A bird was calling for several minutes early Tuesday evening. We had almost given up getting any views when luck finally struck and the bird flew into the beam of my flashlight from which we could follow it for around 5 seconds with some good close-up views - and more than enough for a positive ID!

All and all a very good week, 3 lifers added and some great calls identified. Am already thinking about the next trip upriver.

Folkert, 10/03/2013