Peninsular Thailand, Part 1

While in Peru back in January of 2023, I was having a conversation with Pete Mooney about possible herp trip collaborations. Pete and I have herped together in a number of places, including Peru, and a delightful trip to Cuba a few years earlier. “I’m so jealous of your southern Thailand trip,” I said, speaking of an adventure Pete had the previous year. At the time I had been to Thailand twice, but had not visited the southern peninsula region. As it turned out, Pete was open for a second visit, and so we set the wheels in motion for a June expedition.

As with previous visits, we made our arrangements through TonTan Travel. Our friends Tony and Tan specialize in wildlife tours for small groups. Tony was not available, but Pete and I were in good hands with our guides Bank and Aoud. Bank was our driver, and an excellent naturalist, and Aoud is a working herpetologist in addition to his skills as a guide and naturalist. We made arrangements for Bank and Aoud to meet up with us at Baan Maka, an eco-lodge right outside of Kaeng Krachan National Park, southwest of Bangkok.

A few days before the trip, Pete and I met at Baan Maka, which is a wonderful place to recover from jet lag. The rooms are comfortable, the food is good, and since the place is close to the park, the grounds are loaded with birds, mammals, and herps. We spent some time walking the grounds and letting our internal clocks adjust. Aside from the ubiquitous wall geckos, our first herp was an Oriental Rat Snake (Ptyas mucosa), peeking out of a wall of vegetation.

Baan Maka is a favorite place for birders. We saw a number of interesting birds on the grounds, including the Greater Racket-tailed Drongo (Dicrurus paradiseus) and White-rumped Shama (Copsychus malabaricus). In the trees outside our cabin were a number of Asian Striped Squirrels (Tamiops barbei), lovely creatures with their distinctively striped backs. In the evening, geckos came out to play around the cabins and kitchen – the burly Tokays (Gekko gecko) and the smaller Flat-tailed House Geckos (Hemidactylus platyurus). For me, H. platyurus are one of the more attractive hemidactylids.

Aoud and Bank arrived the next morning, and the four of us headed out to Kaeng Krachan National Park, our first stop on this trip down the Thai peninsula. Thailand’s national parks are a treasure trove of flora and fauna, and Kaeng Krachan is no exception – I saw many herps there on previous visits, so I was quite excited to return again. This huge park extends westward to the border with Myanmar, where it conjoins with Tanintharyi National Park on the Myanmar side.

Driving in on the main park road, we spotted a number of Clouded Monitors (Varanus nebulosus) either crossing or basking on the tarmac. These are medium-to-large lizards, as monitors go, attractive and photogenic, and the juveniles and subadults seem to spend more time off the ground in trees.

Within Kaeng Krachan, there are plenty of places to park and walk along the roadsides and along trails, and these forest-edge situations provide opportunities for finding a lot of different herps, along with butterflies and other insects, and birds of course.

We saw a number of Boulenger’s Pricklenapes (Acanthosaura crucigera), including a few outstanding males showing their breeding colors. These are sturdy, fair-sized agamids that seem to prefer fallen trees and thick bushes. When encountered, they often freeze in place instead of scampering off, giving me a chance to get a few in situ shots with my 100-300 ‘lizard lens’.

A few Asian Vine Snakes (Ahaetulla prasina) were hanging out in the dense green undergrowth. The first one is always difficult to spot, but once your brain acquires the search image for them, they become easier to find. They can exceed a meter in length, and are great photo subjects, occasionally bluff-striking with an open mouth. I know they can bite, but I’ve handled quite a few of these snakes without incident.

We had lunch at the park headquarters, made to order by the park kitchen staff and quite excellent. Sitting at open air tables, there are birds and squirrels and geckos to watch while eating. The roof of the adjacent headquarters usually has a flying snake (Chrysopelea) or two, but none were present this day. However, the large trees by the parking area are home to a number of Olive Tree Skinks (Dasia olivacea), an attractive species to observe and photograph.

The park buildings are also home to a number of Tokay Geckos (Gekko gecko), usually hiding in crevices and dark corners during the day. These are among the largest gecko species, sometimes exceeding 12 inches in length, and some of the biggest I’ve seen have been here at the park. Life at headquarters must be good for Tokays.

A nearby stream has a small group of Dark-throated Leaf Turtles (Cyclemys oldhami). I’ve seen them at the same spot on previous trips and it was good to know they were still around. Turtles are protected within the park of course, and the Thai people don’t seem to hunt and eat turtles to the same degree that other countries do.

Perhaps the most common lizard we encountered (and this held for the whole trip) was Emma Gray’s Garden Lizard (Calotes emma). Much like pricklenapes, they are an edge species, so we saw them quite often along the roadsides and trails. Described by British zoologist John Edward Gray in 1845, the matronym honors his wife Maria Emma Gray, an illustrator and scientist in her own right.

At another stop in the park, this tiny serpent was found crawling out in the open – a neonate Assam Mountain Snake (Plagiopholis nuchalis). These are small (18in) ground-dwelling mountain snakes, feeding on invertebrates, frogs, and small lizards. This snake was tiny, perhaps six inches in total, but it had good body weight and seemed to be doing well.

As evening approached, it was time to leave the park, which is closed at night to allow elephants and other wildlife to move around without dealing with humans and vehicles. We stopped along a roadside outside the park to continue our search for herps, and found several Red-webbed Treefrogs (Rhacophorus rhodopus). This species is included with the group of ‘flying frogs’, which would be better referred to as ‘gliding frogs’, using their fully webbed fingers and toes as parafoils to drop safely from on high. I have yet to see a gliding frog in action, just missing out once in Malaysia because my back was turned.

Our last find near the park was spectacular – a Pope’s Pit Viper (Trimeresurus popeiorum), with gorgeous ruby eyes. This snake was named after American herpetologist Clifford H. Pope, one of my herpetological heroes as a young boy. I had missed seeing this snake on earlier trips, making it a fitting end to the day for me. We headed back to Baan Maka for the evening.

The next day was a busy one – part herping day, part travel day. We planned to return to Kaeng Krachan to see what else we could find, but I had a snake to photograph before we left Baan Maka – a Mock Viper, Psammodynastes pulverulentus, which Bank had found crawling across the grounds. These elapoid snakes do their best to resemble a viper – they will flatten their heads and pull them back into a strike coil, and they even have fake ‘fangs’ at the front of their mouths (they are actually a rear-fanged species). On my last trip to Thailand I took a bite from a pulverulentis, and had a bit of a reaction, so I was more careful with this one.

Returning to Kaeng Krachan, we turned up more monitors, green vine snakes, and pricklenapes, and a few new herps as well. I turned over a log next to the road and was rewarded with the newly described Tree Spirit Bent-toed Gecko, Cyrtodactylus rukhadeva (‘rukhadeva’ is a tree spirit). The best part – this new species was discovered and described by Aoud! That was a cool moment. Cyrtodactylids are one of my favorites and this one had lovely but subtle colors on its dorsum.

We followed the banks of a small stream for a while, and reached a section with large boulders and blocks of stone, all damp and slick with moss. Aoud said there were rock geckos in this specific microhabitat, and after a little searching we managed to spot several Tanintharyi Rock Geckos (Cnemaspis tanintharyi), a secretive species that stayed mostly out of sight and out of light during the day. A difficult species to photograph in situ, but with patience I managed a few shots. They certainly blended in well with the surrounding rock surfaces.

It was time to leave the park and head south down the peninsula. We had a bit of driving to get to our next spot, where we would spend the night and also get in some herping after dark. From here on in, we would be in ‘isthmus herping’ mode – we would spend time herping around Buddhist temples and karst formations up in the hills, we would herp around the lowland mangrove swamps, and any other suitable habitat in between. Down on the coast, we checked into our hotel, and had dinner close to the shore as the light faded.

After eating, we drove to a series of fish impoundments, surrounded by rather aromatic tidal mud flats exposed by an ebb tide. After parking our car on the side of the road, we spotted another Ahaetulla prasina, hanging out in the only tall bush for miles around. It seemed out of place, but what do I know? It looked healthy enough.

As soon as it was dark-dark, our target of the evening appeared – the Bockadam, or Dog-faced Water Snake (Cerberus schneiderii). Bockadams are common snakes among the mangrove swamps and mudflats at low tide. Over the space of 30 minutes or so, we saw more and more of them, emerging from drainpipes and holes in the mud.

These snakes have a few modifications that help them live in this liminal landscape. Their eyes are placed more on the top of the head than on the side, which assists their vision while lying in shallow water and mud. Their nostrils can be closed off to exclude water, and they posses salt-excreting glands as well. When the tide is out, the bockadams hunt fish and invertebrates in the shallow water and mud.

It was an interesting experience, watching these snakes go about their business, while perching on the edge of the mud flats and trying to take photos without pitching over into the deep muck. I got to see several snakes catch and eat small goby-like fish. Bockadams are rear-fanged snakes, but are not considered to be medically significant to humans.

As we wrapped things up on the mud flats, I was thinking it had been a full and productive herping day, but we weren’t done just yet – Bank and Aoud had another stop for us to make. We drove away from the coast and up into the hills, parking alongside a Buddhist temple. The place was deserted, and no longer in use, and the rear of the temple complex butted up against a large escarpment. The karst limestone was riddled with holes and cracks and clefts, and our objective at this place was a newly described pit viper.

We spread out a bit, and as I was poking around the rockface I saw the front half of a Reticulated Python (Malayopython reticulatus), emerging from a rock cleft. We saw each other about the same time, and as I was yelling at the rest of the group, I managed to get a few photos with my phone before it backed away into the rocks. It was gone before the other guys could see it, unfortunately. It was a big one, maybe the biggest snake I’ve seen – I’m fairly sure it was in excess of 4 meters. I’m glad I got a picture or two, so that at least it wasn’t just a one-that-got-away fish story.

Our first pit viper was a small one, high in a bamboo thicket. This was the recently described Kui Buri Pit Viper, Trimeresurus kuiburiensis. During the day, these snakes hide in thick vegetation, and in the cracks and crevices within the limestone escarpments. At night, they come out to hunt frogs and geckos and rodents.

We started seeing more pit vipers, some on rock surfaces, and others in the vegetation, all of them actively hunting for prey items. The largest was perhaps 28-30 inches, and I don’t think they get much bigger than that. All of them were gorgeous, and colored like Christmas; I think the most notable feature was their green ventral scutes.

While photographing a viper, we encountered another snake crawling along on the ground behind us – a Kukri Snake, Oligodon fasciolatus. A good-looking snake, maybe 30 inches in length, and I took a few photos before letting it go about its business. This temple-rock combo was turning out to be a snaky place.

There were quite a few geckos out on the rock faces, also hunting for prey. I saw a number of the familiar Asian House Geckos (Hemidactylus frenatus), but there was something new to me as well – the Sam Roi Yot Leaf-toed Gecko, Dixonius kaweesaki. We saw several of these small geckos, including a colorful juvenile.

Finally it was time to head back to the hotel and grab some sleep, at the end of a long and quite successful day. And thus endeth Part One!