Will Hawkes
E N T O M O L O G Y
Day 3: Into the jungle; sticky frogs and nighttime bees
The river above camp Hornbill
Throwing the last bits of kit in my bag I lugged it from my homestay into the main building of Setulang. Today was a very exciting day as we would be journeying into the Forbidden Forest, Tane’Olen.
Back in the covered pickups we bounced and rumbled up rutted mud tracks before we were dropped at the edge of a river, faces gleaming with excitement. Moving our big bags gratefully into canoes, we waded into the river with just our light day sacks. Well, quite light, mine was full of all my camera equipment and books just in case I saw something very exciting.
With long leaves and tendrils spilling over the path, it wasn’t long before I got too distracted and found myself right at the back hunting for insects. Two beautiful weevils were found Argriorrhynchus sp., a wood boring weevil and Ceocephalus sp. which is apparently ‘very rare’ and mainly eats wood. The latter weevil was pretending to be a stick in the middle of a leaf and so I did wonder whether that was the reason for its rarity.
One black leaf beetle had some incredible anti-predator adaptations: it was covered in very sharp black spines, easily capable of piercing my skin so would get thoroughly stuck in a bird’s throat I imagine!
One odd creature spotted was a stalk-eyed fly that seemed to mimic an ant. I’m hoping to see lots of ant mimics while I’m here, there are lots of reasons for their mimicry, will report back when I have learnt more.
Clockwise from top left: Argriorrhynchus weevil, Ceocephalus weevil, spiky leaf beetle, ant-mimic stalk-eyed fly
Crossing another river, silver darts were swirling seemingly aimlessly through the water at my feet. Giant whirligig beetles! Catching one I was able to have a good look. Their silver body is highly streamlined with an extra pointed ‘nose’ of exoskeleton in front of the eyes to help cut through the water at speed. Interestingly, just one pair of legs remain functional in these beetles which they use as powerful oars. The other 4 legs are reduced to thin, almost negligible sticks. However, my favourite adaptation of these beetles is that each eye is divided top from bottom by a thin line of exoskeleton for protection and streamlining - look both up and down – keeping a lookout for food below and predators above!
Almost without us realising it the trees had got bigger, the canopy higher and the understory more dense and impenetrable. We had entered the primary untouched forest of Tane’Olen.
Giant whirligig beetle
After a good lunch at base camp, group C set off for camp Hornbill! We needed to take all our kit on our backs and so the tight winding track, made more exciting by the rain, was a bit of a struggle to negotiate. I must admit I made it no easier for others by continually stopping abruptly as I had spotted some insect on a neighbouring leaf.
After a little while the camp itself swung into view: one long blue tarpaulin covered the raised wooden planks we would be sleeping on, another covering a table, two small shelters for the loo and the changing room and, most importantly, the kitchen shelter.
Impatiently, Ted, Josh and I threw up our mosquito nets and set off on a quick hunt up river. While Ted and Josh stayed low down frog searching I wandered up the valley side and quickly came across an amazing little creature. This butterfly was sat on a leaf exuding what is known as a ‘hair pencil’ or ‘coremata’ from its bottom. Hair pencils are a form of pheromone signalling apparatus which male butterflies and moths use during courtship. Using air or haemolymph (insect blood) the hair pencil can be ‘fanned’ in and out, wafting the pheromone towards the female. The hair pencil is a multi-use tool: they not only act as attractants to females but also as aphrodisiacs and tranquilisers to ensure a mating! This amazing organ also acts as a repellent to other males of the same species! The composition of the pheromones the male sends out can let the female know his quality and whether it is worth mating with him. I did not see any females around our butterfly however, so he must have been optimistically fanning his pheromones, just in case.
Male butterfly showing off his hair pencil pheromones
Heading back to camp we helped set up a mist net to catch birds in across the river. Looking forward to seeing what we catch tomorrow morning. After a very good tea including some freshly caught fish we set off on a night walk!
As per I very quickly slipped to the very back and found some amazing tailed whip scorpions. As I caught up with the others a large buzzing sound filled the air. Expecting a big beetle I tried to bat the insect onto the ground to have a closer look but after a successful attempt the animal was revealed as a very cross bee, large and orange. It was a carpenter bee (Xylocopa sp.) and I presumed that someone (probably me) had knocked against a branch where it was roosting for the night and woke it up. However, close inspection revealed that this bee had huge eyes! I was puzzling and puzzling about this bee and when I got back to the UK and had internet to look it up I realised it was Xylocopa myops, a nocturnal bee!
Incredibly these bees still forage on even the darkest nights in the jungle on flowers usually 'meant for' moths and bats. This reduces the competition from other pollinating insects and so the bee can forage more than it would otherwise do during the day!
Amazingly, this bee does not have any special senses to help it navigate at night and still relies heavily on vision, hence its massive eyes. She was highly attracted to our headlamps and so to encourage her on her way, we all turned our torches off and staggered down the track until she had lost interest and flown off.
Xylocopa myops, a nocturnal bee!!
Tailed whip-scorpion
Shortly after a small melodic and rhythmic ‘oop’ call invaded our hearing. A definite frog and not one we had seen so far. It was definitely coming from one tree but after a good while searching there was no sign. Just as we were ready to admit defeat and move off, I looked in a small water-filled hole in a fork of the trunk. There sat a tiny little frog, calling hopefully for a mate. This frog is descriptively called the tree-hole frog Metaphrynella sundana. These frogs are quite accomplished musicians. Amazingly, they will try out different holes to compare different resonance and amplification and will even alter their call to optimise the acoustics of their tree-hole!
Tree-hole frog Metaphrynella sundana
Giant Forest Ant Camponotus gigas and its predator the Giant Arboreal Mallinella spider.
On the same tree sat a spider I had been hoping to see: the Giant Arboreal Mallinella. This spider is quite rare and hunts the giant forest ant Camponotus gigas which it also mimics to an extent!
While we were entranced by these small animals, word reached us from the front that a tarsier had been spotted and had subsequently moved off. Grumbling slightly we trudged on, glancing irritably at the sky that had just opened.
Saw less as the downpour made it quite hard to see but an arboreal tarantula lifted spirits!
Arriving back at camp a beautiful orange huntsman was under the bench. However, she quickly dashed off before I could grab a usable photo and so their story may have to wait for another day.
Full of jungle excitement, Josh, Ted and I headed off on a final wander up the river on a frog hunt. I think we found 11 species in the space of half an hour and 50m of river which was incredible. My favourite by far was the first frog I found and enthusiastically grabbed. Quickly I realised the error of my ways as it exuded a white substance that was incredibly sticky. This was a rufous sided sticky frog, Kalophynus pleurostigma. Looking like a leaf this frog seems to tend to sit on the leaf litter on river banks. The sticky defence must be used to deter predators. The substance also seemed to be quite hydrophobic as it kept my hands sticky for a good 20 minutes after I let the frog go!
Arboreal tarantula
Rufous sided sticky frog, Kalophynus pleurostigma
Happy and tired I got under my mosquito net and shut my eyes, looking forward to tomorrow. I had been asleep for about five minutes before I was awoken by a very excited Ted and a black and yellow snake in my face. Jumping up quickly to grab camera we admired this absolutely beautiful mangrove cat snake he had caught! Luckily, Ted is experienced in snake handling but it was still a little exciting watching this snake try and work its jaws around in its mouth to nip him. While not massively venomous this snake would still give you a fairly poor night’s sleep! After safely letting the snake go we headed to bed proper, terribly excited about what the next day would bring!
