While going around west-Java in November 2022, I managed to free up one morning to climb to Cibeureum waterfalls, on the slopes of Gunung Gede in order to document the endemic species of the area. The Gede-Pangrango Natural Park is a UNESCO protected UNESCO site and one of the very few places on Java where natural habitats are fully protected and intact. More than half of the endemic species of animals found in Java occur in the area, including many highly endangered mammals (such as the Javan leopard, Javan gibbon…), birds (Javan hawk-eagle, Javan scops-owl, Javan trogon), reptiles, amphibians (Bleeding toad) and more.
Unfortunately, the rain lasted longer than expected in the morning and most of the charismatic endemics, sought after by most photographers, didn’t show up. But my main focus were lesser-known species such as endemic butterfly subspecies, small mountain passerines and even if the rain lasted nearly half of the morning, I was not disappointed !
Gunung Gede towers at 2900 meters high and my target, the Cibeureum waterfalls are about 1800 meters high. At this altitude, although we are still too low for many of the strict mountain specialist species, we are high enough to start feeling drastic changes of temperature and seeing species that we wouldn’t usually find below this altitudinal range. For a morning hike, this can already give you a great overview of what Java’s lower mountain forests can provide when protected efficiently.
Amongst the local endemics, one of the trickiest to photograph is the diminutive Javan fulvetta (Alcippe pyrrhoptera). This dull-looking passerine rarely comes in the open so I felt fortunate I captured this single shot.
The lower part of the climb is great for partridges and for spotting various primary forest bird species such as minivets, woodpeckers, bulbuls, fulvettas, babblers, cupwings, flycatchers and many more. Gunung Gede’s forest is so thick and moist that observing any animal, no matter how bright its colors are, is a real challenge. On the way up, we spotted three Lesser gymnures (Hylomys suillus suillus), a shrew-like relative to hedgehogs who lives in mountain forests around most of Southeast Asia. We also heard and saw a few squirrels, mostly Black-banded squirrels (Callosciurus nigrovittatus) but the local endemic Mountain three-striped squirrel stayed out of sight. My only reptile of the morning, the Indonesian false bloodsucker (Pseudocalotes tympanistriga) was also spotted while hiking on the lower part of the trail.
Besides the canopy-dwelling butterfly species flying way above me, the only butterflies I saw during the deep forest part of the climb were dark forest-interior specialists such as the local endemic subspecies of the Common faun (Faunis canens canens) that was everywhere near the trail. When I got close to clearings, more butterfly species started to show up but their diversity remained quite low until we got far up enough (about 1700 meters high) in a more open area where, together with my guide, we observed at least 20 butterfly species in a matter of 5 to 10 minutes. This open area is flat, very humid and densely vegetated to about 1.5 meters above ground. It is the perfect habitat for one of the icons of Javan mountains, the endangered Javan hawk-eagle. It is also a great place to spot other birds who can venture near forest edges to find food, especially passerines and woodpeckers.
One of the butterflies I could photograph in the more open habitats was the Malay tailed judy (Abisara savitri atlas), a high-altitude butterfly, here represented by subspecies atlas, endemic to West Java.
The final part of the hike was a mix of steep rocky stairs in deep forest and flatter areas at the bottom of a tall ridge. The waterfalls of Cibeureum waterfall area are impressive during the wet season for their height and the power of the main waterfall. Because the waterfall was near its peak power, not many animals were seen around but a few dozens of meters away, I was fortunate to get great views of a singing pair of Javan tesia (Tesia superciliaris). This small bird is highly coveted by private collectors around Java for its beautiful song, making it likely to get dangerously close to extinction as time goes by if more of its habitat remains unprotected.
The walkway to the Cibeureum waterfall area goes through pristine habitat alongside a tall ridge where langurs, gibbons and lots of birds can be found. This is the habitat of the bleeding toad and the Javan tesia amongst others.
Then come the two highlights of this misty morning around Gunung Gede ! First, while walking on a bridge above one of the humid zones we need to cross to reach the waterfalls, I spotted what looked like a tiny frog on a leaf of a huge plant, just below the walkway. Its dark coloration made it stand out from the bright green vegetation but it was in a bad position so I could only get one decent photo. After carefully looking, I realised that I just photographed a Critically Endangered and restricted range species … no other than the legendary Bleeding toad (Leptophryne cruentata) itself ! Since it was a very small juvenile, it didn’t show the adult coloration yet and was mostly dull but the body shape, location and dark coloration made the ID quite obvious.
The other highlight of the hike was completely unexpected as well as 1800 meters high seems a bit low to photograph this “king” of the mountains. The Javan trogon (Apalharpactes reinwardtii) is now Endangered on IUCN Red List and has a very small range in the mountain forests of west Java. Gunung Gede is known to be the species’ stronghold but it doesn’t make it easy to see by any means. Few photographers have actually managed to capture good photos of this elusive but so stunning bird and my guides were shocked when 3 beautiful adult flew from the top ridge trees and landed just in front of us, remaining there, nearly motionless, for about 10 minutes. What a gift !
The way down was very painful for my feet as my footwear wasn’t optimal for such a difficult terrain but we still got to see quite a few nice species in two big mixed flocks. The descent ended with a very friendly Javan whistling-thrush (Myophonus glaucinus) who hopped about 2 meters away from us and stayed in the open for a couple of minutes, allowing me to get very good record shots despite the low light inside the forest.
This wasn’t a true biodiversity assessment as my time over there was way too short but it is the prelude of a much longer and real biodiversity assessment I am hoping to perform during the coming one or two years. Hiking upwards and downwards this very famous mountain and seeing such beautiful habitat was a true blessing and I can only hope more remaining pristine habitat in beautiful Indonesia will be protected the same way as Gunung Gede-Pangrango National Park !
Until next time !
Pierre de Chabannes