Goodbye Iwokrama

4-12; 5-12; 6-12-2012

After we backpacked back towards the road to Lethum(and we did this in a record speed!) we where picked up by a jeep. During the way back to the field station (a small car ride) we saw a Puma walking. We were really lucky, because Philipe told us that this was the second Puma he saw in the 15 years he worked here. Finally back at the field station to spend our last night there. Before that we packaged our specimens in a substance called cheese cloth. You use this to fold around specimens before putting them in plastic closable zip bags. We had one last late night herping trip where we did not find many species or specimens and the next day we took had a car ride back to Georgetown. During our car trip to Georgetown we again saw a cool mammal: a sloth!

Video of the sloth

The sloth was sitting on the road. It moved, all in line with the species, very slowly. Philipe and Joana grabbed it and moved it towards a tree. The nails/fingers of this three fingered sloth grabbed their fingers fiercely and didn’t want to let go anymore. After we put the animal in the tree, it ran up with all its speed and “disappeared” behind the leaves.

On the last day in Georgetown we had a bit of a vacation day of where we visit a museum, the Iwokrama office (shortly) and some local stores in the city (the markets). Some of us spend their last Gianese dollars at the beautiful Pegasus resort nearby where we had a fabulous meal and drinks. Four hours of sleep where waiting for us that night before we had to check in for the plane that would bring us back to New York and eventually home.

My trip in Guyana and the jungle was a complete new experience for me. It was fairly dry so I didn’t really witnessed the tropical RAINforest, but I did get an impression how collecting specimens is in the field. Collecting specimens for museums as reference specimens of a species is like Philipe said “hard time consuming work which often is forgotten by people working with museum specimens”. People really struggle to get specimens, it can be very hard work under harsh environments. These two weeks have shown this a little bit. We have seen the tip of the iceberg of the biodiversity of reptiles and amphibians in Guyana in these two weeks. In total we’ve seen, and sometimes also captured, 45 species of herps. The trip was tiring but I learned a lot! This was thé trip where the mastercourse of herpetology of the VUB is about. The course where we are actually really searching for and working with the animals we all so love. We all had a lot of fun and for that I’d like to thank my fellow students of this course and off course Philipe as our mentor in the field. Thanks for the unforgettable journey in Guyana!

The whole group

The whole group

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Making plots

3-12-2012

Today was the last full day in the jungle. I had a bit of a dry spell reptile wise until the second of December. That was the day when I found two lizards of the species Gonatodes timidus and caught these (didn’t wrote about this on my blog). In order to at least fulfill the assignment a bit I had to find some specimens today! The assignment was: catch and process two specimens of both 4 species of amphibians and reptiles. I only had two reptile species (with enough specimens), so I needed to collect more. Stressed that I was I badly wanted to find some specimens!

After a few days where none of us was really impressed by what we found in the jungle (not many species) Philipe gave us a new assignment: making plots. We started making plots today, we covered an area of 5 by 5 meter. We removed all the leaf litter. This work was really intensive. The leaf litter wasn’t too thick, but you need to be sure that no herp is present on any leaf. We spend at least one and half hour to make two plots. The results where sadly very meager. We found three small lizards of an yet to be identified species.

Later that day I searched for lizards at the river. The big ones where too fast for me. Luckily, I flipped rocks and stones and happen to find eventually two of the same small lizards during the plots. I’m going to leap forward in time a bit. At the fieldstation we followed with guidance of Philipe a key to determine the species of our lizards. We concluded that all small ones were of the species Coleodactylus settentionalis. I had two specimens so I was lacking one species of reptiles to complete my task. This was going to be the last evening in the forest, since we were about to go back to the fieldstation tomorrow.

Coleodactylus septentrionalis

Coleodactylus septentrionalis

Dear mama,

2-12-2012

Today was the day I almost caught something special. At night I needed to do a number 2. We made an understanding that if one of us needed to do this we would do it at the other side of Turu creek. So I took a small shuffle and hummed a fantastic melody while skipping towards the river. I looked at the river which I needed to cross and I saw two big eyes in it just staring at me. A caiman was glancing at me.

Honestly, the caiman was scared and dove under water, but I was shaking too. I crossed the river and watched out for other things. When I came back the caiman was back too. It was a small sized caiman, approximately 1.5 meter. A Paleosuchus trigonatus, which likely only grows to 2 meters and are restricted to live in smaller rivers.

Afbeelding

Paleosuchus trigonatus

I informed the others at the camp site of the presence of a caiman so nearby. Chris and Joana followed me, because I wanted to catch the specimen (not to process because this species is CITES protected, just for curiosity). We looked for it but we couldn’t see it. Completely dark our headlamps were the only lightsources. Our eyes and lightbeams glided over the water. And then, all of a sudden, it came up to take a breath. It was in the corner of some rocks between a small waterfall of a cascade. It couldn’t go up yet because the cascade was too steep., going down might potentially be dangerous for the caiman cause that meant going town of Turu Falls.

I climbed on the rocks with my big stick which I found near the camp. I reached the same corner as where the caiman was sitting. I illuminated the water and saw the caiman, I pressed it down with my stick and I was ready to grab it. Dear mama, I grabbed the caiman! I had my stick in my right hand and my left hand in its neck to prevent it from biting me. Crocodilidae can produce a big force closing their mouths, but they don’t have strong muscle to open it. Holding your hand in their necks prevents them from snapping. I lifted the animal out of the water. It was large for this species! Than it went wrong..

Chris proposed me to get my stick which was in my right hand. I was too concentrated, but I should have had another free hand. Why? I held the caiman high with my left hand. It moved along motionless. But at a certain point in the air it used all its muscles in its body and it started moving. It made sideway movements and broke loose. It fell into the water, made one snapping move towards me and swum away and dove off the waterfall.

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Turu Falls and its Lake

There I was mama, standing on the top of Turu Falls. Seeing the caiman in the small lake beneath the fall being all pumped up with adrenaline. The caiman’s eyes lit up when I shined light upon it from my headlamp. We stared at each other from a distance. I almost had it! I should have strengthened it with my second arm. I’ve learned something today, I was completely excited by the big adrenaline rush. Mama, this was the day I almost caught my first caiman.

Willem.

Chris’ birthday

1-12-2012

It rained the whole night, the sound of drips falling on the rainfly of the hammock was deafening. The small rainy season appeared to have begun (however it only lasted for a few days). Although I slept in one piece, at the end I felt cold because the forest cools down when it rains. With a whole wet world around me I was happy to put on some dry socks. I grabbed a pair from my bag and put them on. While doing that I thought of Roxanne, my lady, who never cares which one of her socks was meant for her left or right foot while putting them on. I missed her. She was so far away, on the other side of the earth, well, almost.

We processed some animals in the morning to fix these in our collection. After that we had something special: we celebrated a birthday in the forest. Chris randomly went out to do something at a certain point when we were all at the camp site. Maud and Joana fixed the most awesome thing ever. They made a cake consisting of several cupcakes and they had bought a T-shirt. Chris loves turtles and the two girls contacted a first year herpetologist, Achuthan, who can draw like a good camera and asked him to draw a turtle on the shirt . He did and the result is awesome!

Yes, herping wise for me it was a very black day. I haven’t found a new species of herp this day and many with me. Some found new color morphs of Atelopus hoogmoedi. Others found lizards: Kentropix calcarata, Neusticurus rudis and Gonatodes timidus. I did saw various individuals of these lizards today but I did not manage to catch a single one. This made me more and more desperate. Our assignment on this fieldtrip is that we need 2 specimens of 4 species of both reptiles and and amphibians (so 16 specimens at least). I’m already “settled” for the amphibians, since I have 8 specimens. But at this time I only had one reptile species. Seeing lizards but being unable to catch them was really frustrating.

We washed ourselves and our clothes in the Turu Creek. The water of this stream isn’t really warm and yeah I was afraid for parasites. Philipe is convinced that this is a non issue in fast flowing streams. We also used the creek to get our drinking water. Philipe used pills that had to dissolve for two ours to take affect and make the water drinkable.

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Philipe explained us shortly how to record calls. Besides the recording you also need a thermometer to measure the temperature and humidity. You do this to make a better comparison between calls from a site to another, because these variables can affect the call. Later on the evening calling of Rhinella cf. martyi began. Joana recorded a short piece of the call of these toads. Me locating the calling chorus of this toad species was basically my only succesful herping of this day.

Following Turu Creek

30-11-2012

It took some time to fall asleep in my hammock. Finding the right position of laying was difficult at first, you couldn’t notice immediately but if you lay wrongly it could give you some severe back and neck pain the next morning. All in all, sleeping in a hammock beats sleeping in an airplane or at the airport, but nothing is better than just sleeping in a regular bed.

Hammock camp

The hammock camp

Margaret, a Guianese woman and our cook, made us some tasty oatmeal this morning. She resides together with Simon next to the main tent in their own hammocks.

This day we followed the stream, Turu creek which we live next to, downwards. For some of us some exciting finds where made. Gonatodes timidus, a small lizard described by Philipe himself just last year. We saw more of the graceful Atelopus hoogmoedi and last but not least; the deadly venomous snake Bothrops atrox. This animal can kill you with one bite, injecting its deadly venom with its fangs! The greatest danger is its cryptic appearance (can’t see it when its on leaves or any natural background). Luckily, for now, all went right and nothing happened. We caught two individuals.

Later that day we followed the river upstream. Me and Chris found a big boulder there with small ponds on it next to the river. Some of these ponds contained tadpoles, others eggs. We identified them as Hypsiboas boans, a common treefrog from this area. I could not understand why an animal would lay its eggs in a small pond, ready to desiccate in the full sun. Philipe did. He told me that the eggs could hatch with a reduced risk in predation and if it would rain the ponds would flow together, or even flow in the river giving the larvae a larger habitat to complete their development.

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Hypsiboas boans

Since the last days it started to rain more and more. Beside this fact its still very warm with temperatures of 25 degrees in the evening and only 15 at night. Due to the high humidity clothes don’t dry, resulting in no dry clothes. Besides the jungle wetness, which thus doesn’t dry, your sweat also doesn’t dry. Another additional aspect in the jungle is he jungle ingredient coming from plants and getting into your clothes. This whole cascade of substances on not drying clothes results in a fragrance that differs for every person. Everyone starts to smell funky in the jungle.

Margaret cooked us some spaghetti as our evening dish. Joana found later at the same camp site where we ate a species that is very difficult to find, but it just ran in her lap. It was a juvenile of the digging from (which therefor makes it difficult to collect) Synapturans salsari. Normally they are hidden in the ground calling for conspecifics. Jealous as I was on Joana’s beautiful specimen me and Simon tried to search one. We located one beautiful specimen, calling from the ground. It stopped calling if too much people where around and talking or walking. Luckily, Simon has some awesome jungle skills since he’s a native. He easily replicated the exact call of the species resulting in the animal to call back to Simon. This sound is a high pitched whistle and it looks much like Alytes obstetricans know from Europe. Me and Simon started digging, we came close but too bad! The story ends sadly, we didn’t find the animal. The frog disappeared, just as the light of my headlamp at that time since my batteries were low on power. Simon did catch a Osteocephalus taurinus, which I collected as one of my specimens and before going to bed I changed my batteries thinking about my three specimens I collected today: 2 Atelopus hoogmoedi and 1 Osteocephalus taurinus.

Turu Falls

29-11-2012

After our breakfast we knotted some labels to the specimens with rope, to eventually store them in a big bottle filled with formaline. This bottle will keep our whole collection we have gathered so far. We had some more unfinished buseness. The caiman we caught was going to be released and therefor we were about to make photo’s. At first we thought the species was a Melanosuchus niger, instead it appeared to be a Caiman crocodiles. The difference between these two species are the rows of scales in their necks. Another difference is that Melanosuchus can grow up to 6 meters while Caiman is only limited to grow to 2 a 3 meter.

Afbeelding

Me and a Caiman crocodilus

The most exhaustive part of this trip was going to take place this day. We were going to hike towards Turu Falls. This is a large falls of Turu Creek deep in the forest of Guyana. So if one of us would get bitten by a very venomous snake, or whatsoever, we would be screwed. We drove from the field station in the direction of Lethum. After approximately an hour the car stopped. Everyone got their backpacks and we started hiking. Simon, our ranger which was going to stay with us in the forest, was leading the way. We walked fast and there were a lot of obstacles along the way. Crossing a small creek by walking on a fallen tree, going over various hills, zig zag movements through the forest to avoid vegetation etc etc. Finally we arrived at the area where we would stay for four days. Raw nature.

Our porters already left in the morning building our main camp. Completely wet from sweat we arrived at our location. We sat down our stuff and I took a look around. A stream called Turu creek flowed continuously next to our camp. I was mesmerized by the enormous amount of cascades which are present in the river. The deafening sound of water falling down, the stones with moss, water being broken by these massive objects and beautiful vegetation at the river bank with their complementary colors. I loved it!

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Turu Falls

The river banks are inhabited by one of the most beautiful frogs. The name of this critter Atelopus hoogmoedi named after the Dutch herpetologist Hoogmoed. This toad has a very distinctive patterning. Its black with a lot of yellow spots stripes & blotches on it. They sometimes sit and sleep on leaves as kings on thrones. Males can call from these locations to attract potential mates. This species is very common at Turu falls.

After some late night herping where Chris and I found both two treefrogs Hypsiboas boans and two Rhaebo guttatus, which we released. We went to get some sleep in the hammocks for the first time this trip.

It’s all getting fixed baby!

28-11-2012

Until now we have seen 31 species and made specimens out of 24 of these 31 species. We are doing this to make a collection of animals in this area to improve the knowledge on the species in this area. And also of course to teach us where work in the field really is about. This involves not only searching of the animals in the forest, but also fixing the animals in a way that they won’t degrade so that they can be studied indefinitely. The collection of animals and also voucher animals have 3 important purposes. i) Species identification allows correct identification of species, ii) allows studying of intraspecific variation  iii) confirmation of occurance of a species in a certain area. I hereby will explain the steps of fixing herps, and yes sadly this involves killing your specimens. Its sad, but for science! In the end it could make conservation easier by learning more about these beautiful creatures.

There are 6 steps involved into fixing an individual:

1). Prepare formaline. You do this by adding water to formaline powder. A good percentage of formaline to water is 10%.

2). Chytid swabbing – only for amphibians. Chytridiosmycose is a disease which is very widespread and thought to cause a high mortality on numerous amphibian populations around the world. The disease is caused by a chytrid fungus with the name Batrachochytrium dendrobatidis. In order to prevent this disease or learn about the prevalence and more we sample by making skin swabs. This should normally been done directly in the field, however we did this in the lab at the field station. The method we used is 5 swabbings on the following regions: ventrally, thigh, feet and hand. You leave the quetip in a tube which can be later analyzed if the sample indeed contains the fungus. Much like how saliva sampling works in human DNA analysis.

3). Take photo’s – we do this while the animals are still alive because some animals can lose their colors. With photo’s it will always be possible to see some characters in the state of the live form.

4). Kill – We kill by using anesthetics: Lidocain 2%. Amphibians can be killed by putting them in the substance, while bigger amphibians and lizards should be injected with a needle and syringe with this substance.

5). Taking tissues. Avoid to take liver samples. This has been done in the past. However, the liver has a lot of waste product. A good alternative are muscles cells from the legs. Use tweezers and a sharp scapel, clean this with ethanol between procedures and burn to clean it completely. Burning can be performed with a lighter. Take a muscle sample at the thighs, in snakes you could use a sample between the ribs and in some small lizards we could use the liver.

6). Fixing – We fix the animals with the formaline. You use a tray with a paper towel with formaline to put the animals on top of it. You can modify the position of the animal. Eventually you cover all animals in the tray with paper towels drenched in formaline. The formaline results in hardening or stiffening of the animals. Eventually you will have animals that have nice positions to look at characters. For example, it is wise to fix a frog with its feet wide open so its easy to describe the webbing and other characters. Big animals should be additionally injected with formaline to prevent degradation. The whole tray should be kept in the shadow and should be closed with a lit to prevent evaporation.

The result of the fixing process can be seen in the photo. I also would like to point out that Philipe normally does this work alone or with a partner. It can take a lot of time to prepare you specimens this way. Luckily we are with 7 and we could form a production band which speeded up the process.

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Later this day, in the evening, we did some extra additional awesome herping! After the evening dinner, which again was terrific, we left for a boattrip on the Essequito river. We weren’t on the water for a minute and we could already spot two caimans. Simon, our ranger guide, found a snake shortly after that on a twig. I need to inform you that it incredibly difficult to see in the dark with just a headlamp. The banks of the river are filled with trees and other vegetation which make the whole searching for herps a big “Where is wally” game. However, the extra added difficulty is the darkness. Philipe caught the snake, a Corallus hortulanus, professionally with the tong. We weren’t even back in the boat for longer than five minutes and Simon already saw another incredible specimen. This was one was rather high on the tree which hung over the water. Nothing could stop our ranger when he climbed into the tree to get us that snake. Simon climbed and fought against all different obstacles. Pointy needles and stinging ants all over the tree. Simon was though and managed to get the snake down. Which resulted in the second catch of the day.

Another objective was to catch a small caiman. Again, Simon spotted various caimans from a large distance. This is quite easy if they are in the water because of the reflection of light by the retina if you shine upon an animal. The caiman, was not that large and Philipe got it with the tong. However it slipped away and climbed through spiny vegetation on the steep river bank. Two of our rangers went out of the boats and climbed up. After a while one of the rangers located the caiman up on the hill and managed to grab it resulting in the catch of a caiman! Incredebly excited with the catch we went on until we came to a sandbank in the river. After some Hypsiboas and Rhinella marina catching (a quite large one I must say) we saw another small caiman, but larger as the previous one. Philipe used all his skills. He followed the caiman, and plunged in the water. The caiman splashed and swum away, however Philipe jumped again to the caiman. He landed standing half way in water on all fours, sadly, the caiman swum away as fast as he could by using its mighty tail. Nonetheless, the evening was perfect, we finally caught two snakes and even more special, a caiman! Tomorrow will be an exciting day. After breakfast, putting tags on our fixed specimens and making photo’s of the caught individuals of toning we will do something I have never done before! Tomorrow will be the day when we will go into the forest and sleep there for a few days in our hammocks. The real survival days are about to come and I’m nervous, but excited!