Ian Lockwood

MUSINGS, TRIP ACCOUNTS AND IMAGES FROM SOUTH ASIA

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Preliminary Analysis of Land Cover in the Sinharaja Adiviya using Planet Dove Imagery

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Figure 1: Sinharaja Adiviya (or greater Sinharaja area) mapped with Planet Dove imagery. Reduced in size to fit this post.

In March this year I attended a fascinating talk entitled “Sinharaja: From a Timber Reserve to a Biological Treasure Trove. What next?” by Nimal and Savitri Gunatillike at the BMICH in Colombo. The lecture was sponsored by the WNPS in their monthly lecture series. There were several aspects of the talk reflecting back on their decades of research in Sri Lanka’s preeminent forest. Initially, Savitri did botanical studies documenting the diversity of plants in Sinharaja in the period before mechanical logging started (1960s-77). They were witness to period of commercial logging and recovery to a world renowned UNESCO-designated world heritage site. The Gunatilleke’s experiments with rainforest restoration were of particular interest to me, given the lessons that these examples hold for similar non-native plantation areas across the Western Ghats/Sri Lankan biodiversity hotspot. In the lecture, both spoke of the broader Sinharaja area of forest fragments and large patches that are connected or satellites to the core area-something they identified as the Sinharaja Adiviya.

At the same time, I was interested in mapping land cover and forest types in study areas that I take students to for field work. Up to this stage, our DP Geography studies in Sinharaja have utilized Survey Department 1:50,000 and 1:10,000 land use data. It comes as a shape file with the data that I have purchased from their map sales office. This data is satisfactory but we have found significant omissions and inaccuracies in the Kudawa area where OSC students conduct field work (much of the data is based on surveys conducted in the early 1980s).

Forest types and land cover are a key part of the Sinharaja story. Literature about the area’s successful conservation refer to primary  and secondary forest as well as Pinus caribaea plantations (along the border). Yet, I couldn’t locate GIS-ready shapefiles of boundaries of these forest types! The Forest Department has files based on its 2010 forest cover map but these are, thus far, not in the public sphere. I had mapped the area using a Landsat tile from 2005 (published in my blog in 2012) but this was before I had learnt how to conduct a supervised classification of a raster image.

Home garden landscape on the border with Sinharaja rainforest (north west side). (September 2019)

Pinus caribaea plantation in the Sinharaja buffer zone undergoing ecological succession as part of an ecological restoration effort. This area was once dominated by a monoculture community. The intervention of conservationists in thinning pine trees and planting appropriate native species is helping to return it to the climax lowland rainforest community. See linked articles by Professors Mark Ashton, Nimal Gunatillike and others for details of these efforts. (September 2019)

Primary/ridge forest below Moulawella Peak in the Sinharaja core zone. This area did not experience any logging in the period of commercial exploitation in the 1960s-70s. (September 2019)

A Brief Literature Review

A review of land cover analysis in Sinharaja shows that only a few studies have been published to date. The most significant, publicly available study looking at land cover change in Sinharaja was conducted by Buddhika Madurapperuma and Janak Kuruppuarchchi in 2014 (see link). Their analysis used Landsat ETM data between 1993 and 2005 in an area slightly larger than the Sinharaja boundary provided by the Forest Department. They used a Normalized Difference Vegetation Index (NDVI) and Burn Index (BI) to assess changes in three years (2001, 1993 and 2005). The study is thorough but the data that they use is coarse and it is difficult to get a sense of the land cover patterns at a large scale. They conclude with an acknowledgment that ground surveys need to be conducted to better understand the change. Thanura Madusanka Silva published a study entitled “Land Cover Changes of a Tropical Forest Buffer Zone” in 2018 that used Sri Lanka Survey Department data to assess changes in land use in the Kudawa area (see link). This study is based on secondary data and not satellite imagery and it concludes that major change has occurred in home garden areas. There may be other studies that I have missed but the field of land cover change in Sinharaja, as seen in satellite imagery, is ripe for further study.

Figure 2: Supervised classification of land cover based on Planet Dove imagery. Because the images were not collected on the same flight, there are some unavoidable gaps and seams, that are visible on close inspection.

Planet Dove Methodology and Results

Two years ago I became familiar with Planet Dove imagery and saw that it might provide a solution in my attempts to classify land cover in the Sinharaja area. Planet Dove’s constellation of 120+ satellites, which revisit the same areas every day, offers a new opportunity to visualize and analyze any area of the earth. At the beginning of 2019 I successfully applied to Planet’s Education and Research program and was able to download a host of tiles of study areas. I found a series of cloud-free scenes from December 2018 and downloaded them. These are from around December 18 but some were collected at slightly different dates. Using ArcGIS, I mosaiced these various tiles so that I had most of the area Sinharaja Adiviya covered. Because the images were not collected on the same flight there is some unavoidable gaps and visible seams, that are visible on close inspection. The improved spatial resolution of 3-5m means that it is easier to distinguish between different land cover types (lowland rainforest, vs, Pinus caribaea plantation, for example). Initially I worked on a map using the non-visible near infrared (NIR 780-860 nm) layer to highlight vegetation (see figure 1).

In the second part of my efforts I conducted a supervised classification using tools in ArcGIS’s Spatial Analyst extension toolbar. For land cover type, I collected between 5 and 10 training samples and merged each of them into their own distinct land cover type. The classified image (Figure 2) clearly highlights the dense lowland rainforest pockets in a landscape dominated by home garden and tea agriculture. The effort to categorize the Pinus caribaea plantation was partially successful. However, there are errors with some of the classification. For example, plantation in the midst of dense (primary) forest near Moulawella peak.

Conclusion/Future

In the next attempt I plan to collect more training samples in the hopes of getting a more accurate picture of the land cover patterns. A focused study on the pine forest in the buffer area near Kudawa deserves attention. Some of these areas are being successfully restored to their original lowland rainforest vegetation type and time a change study would be illuminating. There are areas of the landscape that I am very familiar with (the Kudawa tourist and village zone) while I have far less personal experience in other areas like western Sinharaja and the various forest fragments. Further studies of landcover need to be verified with ground truthing in the field.

Figure 3: The Kudawa area of Sinharaja with classification of land cover based on Planet Dove imagery. In this image I have highlighted the popular tourist area around the settlement of Kudawa.  The lower part of the map experienced mechanical logging 40+ years ago (some of it is encircled in red). The stream running down to the Sinharaja ticket gate is not depicted on this map and is missing from Survey Department 1:10,000 sheets that were used for the hydro/stream layer.

 

SELECTED REFERENCES (Land Cover Focus)

Ashton, Mark et al.  “Restoration pathways for rain forest in southwest Sri Lanka: A review of concepts and models.” Forest Ecology and Management 154(3):409-430. December 2001. Web.

Ashton, Mark et al.  “Restoration of rain forest beneath pine plantations: A relay floristic model with special application to tropical South Asia.” Forest Ecology and Management 329:351–359. October 2014. Web.

Gunatilleke, Nimal, C.V.S. Gunatilleke and M.A.A. Dilhan. “Plant Biogeography and Conservation of the South Western Hill Forests of Sri Lanka.” The Raffles Bulletin of Zoology, 2005. No. 12 9-22. Web.

Gunatilleke, C.V.S, et al. Ecology of Sinharaja Rain Forest and the Forest Dynamics Plot in Sri Lanka’s Natural World Heritage Site. Colombo: WHT Publications, 2004. Print.

Lockwood, Ian. “Into the Wet: Field Notes From Sri Lanka’s Wet Zone.” Sanctuary Asia. August/September 2007. 3-11. Print. PDF.

Madurapperuma Buddhika  and Kuruppuarachchi Janaka.“Detecting Land-cover Change using Mappable Vegetation Related Indices: A Case Study from the Sinharaja Man and the Biosphere Reserve.” Journal of Tropical Forestry and Environment Vol.4, No 01 (2014) 50-58. May 2014. Web.

Madusanka, Thanura. “Land Cover Changes of Tropical Forest Buffer zone A case study of Kudawa Village, Sinharaja forest buffer zone; Sri Lanka.” International Journal of Scientific and Research Publications. October 2018. Web.

Ministry of Mahaweli Development and Environment. Proceedings of the Stakeholder Workshop on Landscape Planning & Management. 29 September 2017. Web. See page 10 for Sinharaja map.

Planet Team. Planet Application Program Interface: In Space for Life on Earth. San Francisco, CA. 2017. Web.

Sri Lanka Survey Department. District Land Use Maps. 1983. Print/Web.

UN-REDD Programme. Sri Lanka’s Forest Reference Level submission to the UNFCCC. January 2017. Web.

Wijesooriya W. A. D. A. and, C. V. S. Gunatilleke. “Buffer Zone of the Sinharaja Biosphere Reserve in Sri Lanka and Its Management Strategies.” Journal of the National Science Foundation of Sri Lanka. 31(1–2), 57. June 2003. Web.

Written by ianlockwood

2019-09-16 at 7:41 pm

Sri Lanka Mountain Traverse (Part I)

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A collage of diversity: highlights from 10 days of traversing Sri Lanka’s mountain zones.

Sri Lanka’s modest island boundaries hosts a rich assemblage of habitats with unique life forms that contribute to its status as one of 36 global biodiversity hotspots  (together with the Western Ghats of India).  Several of these places-namely Sinharaja rainforest and the Central Highlands -are also recognized by UNESCO as World Heritage Sites. In mid-June this year my son Lenny and I took an unforgettable  ten day south-north traverse through the three most important mountain ranges of Sri Lanka looking to explore themes of endemism.

The Rakwana Hills (including Sinharaja), Central Highlands and Knuckles range share certain geographic and vegetation patterns and yet have distinct species with very restricted distributions. They are all in the “wet zone” receiving between 2,500-6,000 mm of rain (see SL Biodiversity Clearing House Mechanism) . In May this year I read a new article by Sri Lankan amphibian guru Madhava Meegaskumbura and colleagues entitled “Diversification of shrub frogs (Rhacophoridae, Pseudophilautus) in Sri Lanka – Timing and geographic context” (see Molecular Phylogenetics and Evolution and the summary by Dilrukshi Handunnetti in Mongabay). The authors highlight the genus Pseudophilautus in the three ranges and their connections to shrub frogs in the Western Ghats. They delve deep into the species at a molecular level that is beyond most of us but I was fascinated by the role of mountain geography in the species’ distribution. This got me thinking about doing a single traverse through the same ranges at the onset of the South West Monsoon.

About the same time, Lenny was formulating an approach to his IB MYP5 personal project. This culminating exercise challenges students to pick their own project, make a product or produce an outcome and then reflect deeply on the process. He had been fascinated by our (thus far, futile) search for the rare point endemic marbled streamlined frog (Nannophrys marmorata) in the Knuckles range. With a little encouragement from his parents, Lenny decided to explore broad themes of endemism in Sri Lanka using the medium of photography.

Primary ridge forest in Western Sinharaja. These relatively inaccessible areas were never logged during the mechanized logging period (1960s-mid 1970s). The prominent tree species is Shorea trapezifolia from the Dipterocarpaceae family.

Sinharaja West

We started our 10 day traverse, driving southwards from Colombo on the expressway in the middle of heavy monsoon showers. Our first three days and two nights were spent in the western side of Sinharaja, staying with the incomparable Martin Wijeysinghe at his Jungle Lodge. There were showers on all days but this was low season and there were few tourists (and no migrant birds). The road that had been re-paved from the Kudawa ticket office up to the entrance to the core zone entrance was nearly complete and opened for the first time. The impact of this controversial project appeared less harmful than had been projected by concerned citizens and journalists (See the Daily Mirror on 12 February 2019). Pavement stones had been used on the road and a concrete lining put on the storm drain that runs parallel down the road. There were some trees that had been felled and large patches of Strobilanthes and other shrubs cleared. But these should recover within a season or two. If there is one lesson from Sinharaja’s conservation story in the last 40 years it is that the rainforest system is resilient and is able to recover from human disturbance remarkably well. That doesn’t suggest that we should be complacent about conservation and restoration efforts but we do need to give the system a chance to rebound.

Lenny, Amy and I had visited Martin’s for two nights in February along with our friend Mangala Karaunaratne and his two kids. That trip had been rewarding with good sighting of the Golden Civet Cat (Paradoxurus zeylonensis), Blue Magpies (Urocissa ornata), Hump Nosed Lizard (Lyriocephalus scutatus) and several other species. A few of the images are included here, as they paved the way for a deeper exploration of the area.

The extremely rare Golden Palm Civet Cat (Paradoxurus zeylonensis) at Martin’s lodge. This individual made regular night visits for several months but has stopped coming (as of June 2019). (photo taken in January 2019)

Our highlights with endemics in the western part of Sinharaja in June mainly involved birds. We did look for frogs around Martin’s but were not that successful in this early stage of our mountain traverse. During our three days we had rewarding encounters with a Green Billed Coucal (Centropus chlororhynchos), a pair of Sri Lanka Frogmouths (Batrachostomus moniliger), Blue Magpies (Urocissa ornata) and a Green Pit Viper (Trimeresurus trigonocephalus). Thilak, the very talented independent guide, helped us locate a solitary Chestnut Backed Owlet (Glaucidium castanotum). We did encounter a mixed feeding flock during our first walk to the research station. It included some of the usual endemics but we didn’t have a good opportunity to photograph them.  A visitor from Singapore staying at Martin’s was very lucky and saw both the Serendib Scops Owl (Otus thilohoffmanni) and the extremely rare Sri Lanka Bay Owl (Phodilus assimilis) in the same area while we were there.

Harpactes_fasciatus_Sinharaja_1(MR)(06_19)

A male Malabar trogon (Harpactes fasciatus) that was part of a mixed species feeding flock near the Sinharaja research station.  Regular readers may recognize that this species is one of my favorite species to encounter and photograph. Previous posts from Silent Valley and the Palani Hills have feature Malabar Trogons and a future post from Thattekad (Kerala)will highlight another exquisite individual.

T_trigonocephalus_at_Sinharaja_tongue_1a(MR)(6_19)

Sri Lanka Green Pit Viper (Trimeresurus trigonocephalus) near the upper Core Zone entrance on Sinharaja’s west side.

Sri Lanka Blue Magpie (Urocissa ornata) visiting Martin’s lodge, in search of months and insects around tea time before breakfast.

Sri Lanka Keelback (Xenochrophis asperrmus) at the ticket gate of the Kudawa entrance to Sinharaja.

Glaucidium_castanotum_at_Sinharaja_3a(MR)(06_19)

The endemic and diminutive Chesnut Backed Owlet (Glaucidium castanotum) was one that took special help to find. Lenny and I were assisted by Thilak, the independent guide, in our search for owls and he found this individual outside of the park boundaries. Just was we were setting up and getting shots with a 200-500 the skies opened up and we were forced to leave before we wanted to. The light was so low and the bird was at least 20 meters away and I was forced to use a strobe.

(to be continued in Part II/IV)

REFERENCES (for all four parts)

Amphibian Survival Alliance. Web.

De Silva, Anslem. Amphibians of Sri Lanka: A Photographic Guide to Common Frogs, Toad Caecilians. Published by author, 2009. Print.

De Silva, Anslem and Kanishka Ukuwela. A Naturalist’s Guide to the Reptiles of Sri Lanka. Colombo: Vijitha Yapa Publishing, 2017. Print.

Gunatilleke, C.V.S. A Nature Guide to the World’s End Trail, Horton Plains. Colombo: Department of Wildlife Conservation, 2007. Print.

Gunatilleke, I.A.U.N, and C.V.S. Gunatilleke and M.A.A. Dilhan. “Plant Biogeography and Conservation of the South Western Hill Forests of Sri Lanka.” The Raffles Bulletin of Zoology, 2005. No. 12 9-22. Web.

Handunnetti, Dilrukshi. “How India’s shrub frogs crossed a bridge to Sri Lanka – and changed forever.” Mongabay. 1 May 2019. Web.

Kotagama, Sarath and Gamini Ratnavira. An Illustrated Guide to the Birds of Sri Lanka. Colombo: FOGSL, 2010. Print.

Meegaskumbura, Madhava et al. “Conservation and biogeography of threatened Amphibians of Eastern Sinharaja.” Froglog. Issue 100. January 2012. Web.

Meegaskumbura, Madhava et al. “Diversification of shrub frogs (Rhacophoridae, Pseudophilautus) in Sri Lanka-Timing and geographic context.” Molecular Phylogenetics and Evolution. 2019. Web.

Pethiyagoda, Rohan. Horton Plains: Sri Lanka’s Cloud Forest National Park. Colombo: WHT, 2013. Print.

Protected Planet. Sri Lanka PA Boundaries. August 2019.

Senevirathna, Ishanda. The Peeping Frogs of Nuwara Eliya. Colombo: Jetwings, 2018. Print.

Somaweera, Ruchira and Nilusha Somaweera. Lizards of Sri Lanka. A Colour Guide with Field Keys. Frankfurt: Edition Chimaira, 2009. Print.

 

MAP OF THE JOURNEY

 

Sri Lanka Mountain Traverse (Part II)

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Montane forest interior with remnant cardamom plants under the low canopy of the rainforest.

Sinharaja East

Moving on from Kudawa, Lenny and I rejoined the Kalawana-Rakwana (B181) road and followed its winding course eastwards and parallel to the norther borders of Sinharaja. We left the heavy monsoon clouds of the wet zone as we drove up and then descended into the drier side of the hills that Rakwana sits in. Our time in the intermediate zone was brief as we were headed back up into the higher hills that are exposed to the South West Monsoon. Our destination was Morningside: a relatively remote area that is renowned for its plant and amphibian diversity.

Looking south to Handapana from the Kalawana-Rakwana road. This is technically not part of the Sinharaja protected area but it is a critical forest habitat harboring many key species.

The forest department bungalow at Morningside sits at about 1,000 meters in an area of dense montane rainforest. The species composition is unique and the forest structure is noticeably different (shorter) than the lowland rainforest of western Sinharaja where we had just been. Tea estates, with patchy gardens that look difficult to maintain, form a barrier between the Suriyakanda (A17) road and the forest interiors. We entered on the shorter south road through the Morningside tea estate and later left on the northern road. The area near the Morningside bungalow was once cleared for tea cultivation and plantations of Australian Acacia sp. There had been efforts to plant cardamom in the area and we came across the plants surviving on the forest floor. Most of the plantation efforts failed and cleared areas are gradually reverting to the native montane evergreen forest (with some assistance from restoration planting activities). Because of the physical differences (especially altitude) with the rest of Sinharaja  there are species not found in either Kudawa or Pitadeniya to look out for. Amphibians and lizards were what we were focused on but we were interested to learn more about the area and all its life forms.

Learning more about Morningside and Sinharaja was greatly helped along when we were joined by Nimal Gunatilleke, distinguished professor emeritus from Peradeniya University. I had attended the fascinating public talk on Sinharaja in March sponsored by WNPS on Sinharaja by Nimal and his wife, professor Savitri Gunatilleke. In May I had spoken with them and shared stories about Sinharaja and my interest in similar areas in the Western Ghats. By happy coincidence Nimal was going to be conducting a workshop in Deniyaya in June and so I had invited him to join us once I had made the Morningside booking with the FD.

Ride_to_Morningside_2a(MR)(06_19)

Norther approach to Morningside bungalow- showing a mix of montane forest, tea and weeds.

Having left Kudawa in the morning Lenny and I met up with Professor Gunatilleke in Rakwana, bought our supplies and then proceeded to Morningside together. In Suriyakanda, Lenny and I switched into a hired Bolero pickup that took us on the last hour to the FD bungalow. There was no rain cover and the road was very rough. We were relieved to arrive dry, though a bit stirred and shaken. Nimal and his driver followed us in a well-used Mitsubishi pick up from the university.

During our first two days Lenny and I enjoyed several insightful conversations and slow walks with Professor Gunatilleke where I learnt a great deal about the area’s plants and efforts to restore the degraded landscapes. Photographically-speaking, daylight hours were relatively unproductive but when it got dark a host of creatures came to life in the mossy forest behind the bungalow. Lenny and I went in prepared for leaches and rain but were lucky that it was not pouring on either nights and there were very few blood suckers. We honed our frog sighting skills on the first night and tripled our species count on the second night. Our approach was to locate the frogs listening to their calls in the dark, used torches to locate them and then photographed them in situ with minimal changes using two and sometimes three portables strobes.

It was only after we returned to Colombo that we got confirmation on what we had photographed on the FB pages of the Amphibian of Sri Lanka  (and Reptiles & Amphibians of Sri Lanka) groups. Another key resource for Morningside’s frogs was Meegaskumbura et al.’s “Conservation & biogeography of threatened amphibians of Eastern Sinharaja” from Froglog (published in 2012). (Nimal Gunatilleke is one of the authors on this short, but helpful publication)

Our first frog spotted was the critically endangered Morningside Hourglass frog (Taruga fastigo) – we actually mistook it for the endangered Montane Hourglass (Taruga eques) that I have previously photographed in Nuwara Eliya and Peak Wilderness. The Morningside species is a point endemic with very restricted distribution. Lenny located at least two bright green Poppy’s Shrub frogs (Pseudophilautus poppiae) and I found a third. This endangered frog is one of the most distinguished at Morningside. We also found the Golden Shrub frog (Pseudophilautus auratus) as well as several others that we are still working on identifying. We desperately wanted to photograph the lizards (Desilva’s Erdelen’s Horn, and Karunaratne’s Horn) that Morningside is well known for but aside from one that ran across the path in front of me, we had no worthy sightings.

Pseudophilautus_auratus_ES_1a(MR)(06_19)

Pseudophilautus auratus at Morningside.

Pseudophilautus_sp_dark_green_ES_1(MR)(06_19)

Pseudophilautus cavirostris at Morningside.

My personal highlight was the very camouflaged Tibetan Bubble Nest/Hollow Snouted Shrub Frog that I located from its call clinging to the mossy bark of a medium-sized tree. Based on other photographs on the FB group, I believe that this is Pseudophilautus cavirostris. Trying to get its eye in focus while aiming two strobes at different angles in a wet tangle of vegetation was a challenge but we both got decent photographs.

Several years ago we had stayed at the Rainforest Ecolodge (see my 2012 posts) – a place that is in a similar montane habitat on the edge of tea and rainforest. On the map it is a short distance away but the area between the two locations is seemingly impenetrable with thick, barbed cane (Canus sp.) stands and dense forest. There was no obvious path to follow other than the stream that flows westwards to the lodge.

On June 13th, the jeep driver, picked us up and drove us back towards Suriyakanda via the longer norther approach. The morning was damp and cool with a veil of mist hanging just above the gnarled rainforest canopy. We heard the loud chattering of Blue Magpies (Urocissa ornata) and the distinct call of Sri Lanka Spur Fowl (Galloperdix bicalcarata) but other than a fleeting glimpse of Yellow Eared Bulbuls (Pycnonotus penicillatus) there were few birds to be seen. Overhanging branches and lianas crowded the road and the drive was far more exciting than any roller coaster ride. The bench seat was recycled from another vehicle and only attached with nylon rope to the back bed of the pickup. When the wheels hit a bump, the rope stretched and gave flight to the seat and us passengers. Trying to stay in the vehicle on the anything-but-smooth trail and dodging branches was an exciting, albeit  life-threatening part of getting back to our own vehicle. We passed the junction of the once proposed road that would connect Suriyakanda with Pothupitiya/Illuokanda (see Malaga Rodrigo’s Sunday Times 2011 article). Thankfully it is overgrown and there is no evidence of a road or plan to build one. We unloaded the pick up and repacked our truck for the onward traverse-heading north to the lofty Central Highlands.

(to be continued in Part III/IV)

 

REFERENCES (Morning Side)

Amphibian Survival Alliance. Web.

De Silva, Anslem. Amphibians of Sri Lanka: A Photographic Guide to Common Frogs, Toad Caecilians. Published by author, 2009. Print.

De Silva, Anslem and Kanishka Ukuwela. A Naturalist’s Guide to the Reptiles of Sri Lanka. Colombo: Vijitha Yapa Publishing, 2017. Print.

Gunatilleke, I.A.U.N, and C.V.S. Gunatilleke and M.A.A. Dilhan. “Plant Biogeography and Conservation of the South Western Hill Forests of Sri Lanka.” The Raffles Bulletin of Zoology, 2005. No. 12 9-22. Web.

Handunnetti, Dilrukshi. “How India’s shrub frogs crossed a bridge to Sri Lanka – and changed forever.” Mongabay. 1 May 2019. Web.

Kotagama, Sarath and Gamini Ratnavira. An Illustrated Guide to the Birds of Sri Lanka. Colombo: FOGSL, 2010. Print.

Meegaskumbura, Madhava et al. “Conservation and biogeography of threatened Amphibians of Eastern Sinharaja.” Froglog. Issue 100. January 2012. Web.

Meegaskumbura, Madhava et al. “Diversification of shrub frogs (Rhacophoridae, Pseudophilautus) in Sri Lanka-Timing and geographic context.” Molecular Phylogenetics and Evolution. 2019. Web.

Protected Planet. Sri Lanka PA Boundaries. August 2019.

Somaweera, Ruchira and Nilusha Somaweera. Lizards of Sri Lanka. A Colour Guide with Field Keys. Frankfurt: Edition Chimaira, 2009. Print.

Sri Lanka Mountain Traverse (Part III)

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Tree ferns (Cyathea gigantean) at the Hakgala Botanical gardens. These plants with ancient features are a key part of montane ecosystems in Sri Lanka’s Central highlands as well as the Western Ghats of southern India.

The Rakwana Hills are separated from the Central Highlands by several valleys and lesser east-west ridge lines. Just above Rakwana you get a glorious view out across to Sri Pada, Horton Plains, and the dramatic southern escarpment of the Central Highlands. We drove from Suriyakanda, down to Rakwana and then to Pelmadulla, Balangoda and Belihul Oya before making the gradual ascent to Haputale-the virtual gateway to the upper Central Highlands. The geographic barrier of the lower valleys has been significant enough to lead to speciation and distinct characteristics of each habitat. Now, as we neared the half way point of our 10 day adventure, Lenny and I were eager to continue our search for the endemic amphibians, lizards and birds of the Central Highlands.

Looking north from near Handapana over Rakwana town to the distant hills of the Central Highlands.

The view at Belihul Oya: looking up to the southern escarpment of the Central Highlands and the edges of Horton Plains National Park. The steep slopes have a mix of grasses and Pinus sp. plantations.

June 15th, the view at Haputale: Looking south from the southern escarpment back over the lower plains to Hambantota and the Indian Ocean. The pilgrimage site of Katragama and its hills as well as large container ships were visible through binoculars.

Breaking for a night in Haputale (altitude: 1,400 m) we refreshed ourselves, charged camera batteries and prepared for a brief exploration of the Central Highlands. On June 14th we drove the newly paved road from Haputale to the eastern entrance to Horton Plains National Park. It crosses train tracks, meanders through densely cultivated valleys of cool-climate vegetables and then ascends steeply through eucalyptus plantations before ending up on the plateau of Horton Plains (altitude: 2,100 m). The drive, with its narrow, extremely steep approach was challenging but we made it and were rewarded with good weather and clear views out across to Hambantota and the Indian Ocean.

Arriving at the eastern edge (altitude @2,100m) of Horton Plains National Park with good views looking south.

The highlight in Horton Plains was a successful search for the endemic Rhino Horned Lizard (Ceratophora stoddartii) near the entrance. There is a Ceratophora species in each of the three ranges that we were visiting and eventually we would see and photograph two of the three. We also looked for the Pygmy lizard (Cophotis ceylanica) and the enigmatic Sri Lanka Whistling Thrush (Myophonus blighi) but were not able to find either of them. The drive to the hill station of Nuwara Eliya took us off the high plateau to a slightly lower area of rolling hills. These areas are used for dairy agriculture and the Ambawella farms has stunning fields of green with scattered cloud forest trees (notably the distinctly shaped Calolphyllum walkeri).

Mist at the Arenga pool in Horton Plains National Park.

Our two nights in Nuwara Eliya were focused on doing the night frog tours at Jetwings’ St. Andrew’s Hotel. I had told Lenny about previous tours on OSC’s WWW trips and they had been central to our plan of exploring endemism in Sri Lanka. The hotel’s naturalist Dinesh Sampath, who had provided guidance for my students in January, took us out on both nights. It was surprisingly dry-so much so that the ponds and stream had very little water in them. Nevertheless, we did well with our amphibian treasure hunting. The highlight was finding an unusual orange morph of the Leaf-nesting Frog (Pseudophilautus femoralis). As the name implies, this is usually a bright green frog but the three juveniles that Lenny found on a raspberry bush thicket had a distinctly orange coloration! We spotted the other six endemics that are normally seen on the frog tour so it was two worthwhile nights.

 

During the full day we had in Nuwara Eliya Lenny and I took a short visit to the Hakgala Botanical Gardens. It was a terrifically bright blue-sky day with crisp mountain air. Our highlight in Hakgala was having the opportunity to spend an extended period of time with the Bear Monkeys (Semnopithecus vetulus monticola) and Toque Macaques (Macaca sinica) that are resident in trees near the rose garden. Both are endemic species and it was good to check off some mammals.

An unusual morph of the Dull Green shrub Frog (Pseudophilautus viridis) at Nuwara Eliya

On June 16th we wrapped up the Central Highlands leg of our journey and headed for the final destination-the Knuckles range!

 

(to be continued in Part IV/IV)

REFERENCES (HPNP/NUWARA ELIYA)

Amphibian Survival Alliance. Web.

De Silva, Anslem. Amphibians of Sri Lanka: A Photographic Guide to Common Frogs, Toad Caecilians. Published by author, 2009. Print.

Gunatilleke, C.V.S. A Nature Guide to the World’s End Trail, Horton Plains. Colombo: Department of Wildlife Conservation, 2007. Print.

Handunnetti, Dilrukshi. “How India’s shrub frogs crossed a bridge to Sri Lanka – and changed forever.” Mongabay. 1 May 2019. Web.

Kotagama, Sarath and Gamini Ratnavira. An Illustrated Guide to the Birds of Sri Lanka. Colombo: FOGSL, 2010. Print.

Meegaskumbura, Madhava et al. “Diversification of shrub frogs (Rhacophoridae, Pseudophilautus) in Sri Lanka-Timing and geographic context.” Molecular Phylogenetics and Evolution. 2019. Web.

Pethiyagoda, Rohan. Horton Plains: Sri Lanka’s Cloud Forest National Park. Colombo: WHT, 2013. Print.

Protected Planet. Sri Lanka PA Boundaries. August 2019.  Horton Plains National Park

Senevirathna, Ishanda. The Peeping Frogs of Nuwara Eliya. Colombo: Jetwings, 2018. Print.

Somaweera, Ruchira and Nilusha Somaweera. Lizards of Sri Lanka. A Colour Guide with Field Keys. Frankfurt: Edition Chimaira, 2009. Print.

Sri Lanka Mountain Traverse (Part IV)

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The Knuckles Range, also known as the Dumbara Hills, as seen from the east with the South West monsoon billowing up over the edges.

The Knuckles Range, also known as the Dumbara Hills, are a relative enigmatic area that was the last point on our Sri Lankan three-mountain-range traverse. Lenny and I had been on the Riverston side in October of last year with the whole family (see blogpost) but we wanted to go back with a focus on amphibians. This time, with the goal of visiting the last of the three major mountain ranges of Sri Lanka on a single journey, we planned a route that would take us to the Knuckles on a new approach.

Leaving Nuwara Eliya on a crisp morning, we drove out on the north-eastern side of Pidurutalagala, Sri Lanka’s highest peak (2,524m). Other than a crown of cloud forest, this side of the Central Highlands is heavily cultivated and populated. The road (B332) passes through Kandapola and Walapne before descending into the Mahaweli valley through the Victoria Randenigala Rantembe Sanctuary. The Randenigala dam, controlling the outflow of Sri Lanka’s longest river is a major landmark in the dry forested landscape. W the southern Mahaweli  flood plains we passed through Mahiyanganaya on posun poya and the road was crowded with families out for dansal. The surrounding area has relatively low rainfall but enjoys the fruits of the massive Mahaweli Valley irrigation system. The landscape seems to be perpetually green and gold with paddy being grown and harvested throughout the year. Driving along the plains to the east of the Knuckles, we observed dramatic activity of the south west monsoon over the hills (see B&W)cover pictures and panorama).

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Dramatic activity of the south west monsoon over the Knuckles range north of Mahiyanganaya

The recently filled Kalu Ganga dam on the Hettipola-Rattota road.

Looking south on the steep drive up to the Pitawala Pantana and Riverston on the Hettipola-Rattota road.

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Northern valleys of the Knuckles range as seen from the road north of Riverston.

The drive up to Riverston from Hettipola took a route around the recently flooded Kalu Ganga reservoir-Sri Lanka’s newest large hydroelectric project. The town of Pallegama, that we had driven through in October 2018, is now fully submerged. When we passed through, families were removing their last door frames, roofs and materials in anticipation of the flooding. Conditions in the exquisite dry and semi evergreen forest on the ascent were parched-the area is clearly in the rain shadow of the  Knuckles.

Once again, we enjoyed the comforts and hospitality of Sir John’s Bungalow, the small boutique hotel located just below Riverston. This was low season and, generally speaking, tourists numbers in Sri Lanka were thin as a result of the Easter Sunday bombings. But we didn’t complain about being the only guests. Nadeera Weerasinghe, the manager and super naturalist at Sir John’s, warmly welcomed us and we immediately started to plan amphibian outings.

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Lenny searching (in vain) for the rare point endemic marbled streamlined frog (Nannophrys marmorata) in the Knuckles range. Conditions were simply too dry and we could not find any sign of them on this trip.

The cloud forest at Riverston provides a rich area for amphibians and reptiles. The area receives significant of rain from the South West Monsoon and is located above 1,400 meters. Riverston is named for the peak with TV transmission towers on the Ratotta-Hettipola road (B274). The saddle or ‘gap’ where the road crosses a high point is quickly becoming a local tourist point of interest and now has several temporary shops selling carbonated drinks and hot snacks. Visitors come to walk up to the towers and a few come for the biodiversity. However, the area lacks any formal conservation management and the usual issues of solid waste, noise and carelessness are growing into alarming threats to the area’s serenity. During our full day we went with Nadeera up to Riverston to look for lizards. Lenny and I were able to find several fine examples of the endemic Leaf Nosed Lizard (Ceratophora tennentii) and Nadeera tracked down a single but rather shy and difficult to photograph Knuckles Pygmy Lizard (Caphotis dumbara).

Our search for amphibians was quite successful in spite of the dry conditions. We did look for Nannophrys marmorata but their stream habitat on Pitawala Panthana was almost completely dried up (a normal situation given that this was the direst time of the year at these natural grasslands). Further down the hill, Nadeera took us on a productive night outing in the dry evergreen forest with his naturalist friend Kais (KC). Notably we found two different female Hump Nosed Lizards (Lyriocephalus scutatus) and an array of intermediate zone frogs. During our 2nd and last night I went with Nadeera up to Riverston, where the forest is of course wetter and has different species. In about 90 minutes of looking we came across almost a dozen Pseudophilautus individuals including the green P. stuarti. At the time of writing I am still working on identifying the species from both of these walks.

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Most likely Pseudophilautus stuartii at Riverston, Knuckles.

On June 18th after ten days in the field, Lenny and I bade goodbye to the Knuckles and headed back to Colombo. Our final leg took us down the steep Ratotta valley into Matale and then over the low hills to Kurunegala. We knew that we would have to return to find our reticent Nannophrys marmorata that had kick started the search but we felt accomplished in all that we had seen, experienced and photographed.

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Dawn panorama above the panthana on the road to Riverston.

REFERENCES (KNUCKLES)

Amphibian Survival Alliance. Web.

Bambaradeniya Channa and S P Ekanayake. A Guide to the Biodiversity of the Knuckles Forest Range. Colombo: IUCN. 2003. Print.

De Silva, Anslem. Amphibians of Sri Lanka: A Photographic Guide to Common Frogs, Toads Caecilians. Published by author, 2009. Print.

De Silva, Anslem, Ed.  The Diversity of the Dumbara Mountains. (Lyriocephalus Special Issue). November 2005. Amphibia and Reptile Research Organization of Sri Lanka. Print.

De Silva, Anslem and Kanishka Ukuwela. A Naturalist’s Guide to the Reptiles of Sri Lanka. Colombo: Vijitha Yapa Publishing, 2017. Print.

Handunnetti, Dilrukshi. “How India’s shrub frogs crossed a bridge to Sri Lanka – and changed forever.” Mongabay. 1 May 2019. Web.

Kotagama, Sarath and Gamini Ratnavira. An Illustrated Guide to the Birds of Sri Lanka. Colombo: FOGSL, 2010. Print.

Meegaskumbura, Madhava et al. “Conservation and biogeography of threatened Amphibians of Eastern Sinharaja.” Froglog. Issue 100. January 2012. Web.

Meegaskumbura, Madhava et al. “Diversification of shrub frogs (Rhacophoridae, Pseudophilautus) in Sri Lanka-Timing and geographic context.” Molecular Phylogenetics and Evolution. 2019. Web.

Protected Planet. Sri Lanka PA Boundaries. August 2019.

Singhalage Darshani, Nadeera Weerasinghe and Gehan de Silva Wijeratne. A Naturalist’s Guide to the Flowers of Sri Lanka. Colombo: Vijitha Yapa Publications, 2018. Print.

Somaweera, Ruchira and Nilusha Somaweera. Lizards of Sri Lanka. A Colour Guide with Field Keys. Frankfurt: Edition Chimaira, 2009. Print.

Mannar: Feathers & Frogs on a 2019 Visit

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Black-headed Gulls (Chroicocephalus ridibundus)(non-breeding plumage) on the beach at Pesalai fishing beach (northern coast of Mannar) .

The island of Mannar and Wilpattu National Park continue to be must visit destinations for birdwatchers in Sri Lanka. Last November our friend Pippa Mukherjee visited and we took her up to Wilpattu for an introductory visit.  More recently, in February, we had a long poya weekend that allowed us an opportunity to revisit this far corner of Sri Lanka.

On the February trip we had four days to get up to Mannar and back. That’s not a long time given the distance (@ 320 km from Colombo) and all the nice things to explore on the way. On the journey driving from Colombo we overnighted at the Backwaters Lodge north of Puttalam before continuing on the next day up to Mannar. The Backwaters offers a convenient place to access Wilpattu’s south-western entrance and to do local birdwatching in excellent dry zone thorn forest. This was my second visit and I was interested in trying to see the Indian Chameleon (Chamaeleo zeylanicus)in the surrounding thorn forest. The owners Tarique Omar and Ajith Ratnayaka were both on site for this visit and I enjoyed speaking to them about the area and their story in setting up Backwaters. The family took a rest (it was hot and dry) while I went out to look for Chameleons with their guide Sanoos. It was the middle of the day with hot, bright conditions-perfect for these reptiles I thought. Unfortunately, despite our best efforts, no Chameleons were to be found. The area where Chameleons are found hosts some excellent arid zone tropical thorn forest. I marveled at the unappreciated vegetation and was reminded that much of the south-eastern Indian plains also hosted similar systems. Unfortunately it is also the site of a lime stone pit mine and the proposed solid waste dump of Aruwakkalu.

Moonrise over the Nelum Wewa wetlands and tank near to the Wilpattu south-west entrance.

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Jerdon’s Nightjar(Caprimulgus atripennis) at Backwaters.

Rather than drive around via Tantirimale, we went to Mannar driving through the western dirt track that runs through Wilpattu. It is shorter (in terms of km traveled) and there are opportunities to see and appreciate Wilpattu’s forests, wetlands and classic wildlife. The only hitch is the approach over a sometimes flooded causeway and the few kilometers of seriously beat up road. There had been rains and we drove over the causeway with about 10 cm of water-not too dangerous but getting close, it seemed to me. On the road we enjoyed an encounter with a bull elephant, Malabar pied hornbill flyovers and numerous mongoose encounters. We were happy to have our high clearance 4×4 vehicle for the journey. The stretch from the northern Wilpattu entrance to the Mannar causeway passes through an exceedingly dry landscape. Some of this has been controversially cleared of the appreciated thorn forest and allocated to house former IDPs from the conflict and tsunami. The arid conditions make it an exceedingly difficult place to eke out a living it seems to me.  Very few the newly constructed houses showed signs of life. It is only on the approach to Vankalai Sanctuary that the road runs through rich agricultural lands that benefit from tank (especially Giant’s Tank) irrigation. The area that once house the famous Pearl fisheries is fascinating. The beaches are desolate and seemingly pristine- all very eerie given that this stretch of coastline hosted the immensely productive pearl fishing communities for several hundred years before being overfished at the end of the 19th Century . The ruins of Fredrick North’s bungalow are the only reminders about a very different past. He was the Governor of Ceylon (1798-1805) soon after the British took over.

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On this visit we returned to the Palmyrah House, the island’s most comfortable accommodation that the kids and I had stayed at several years ago. It has since been refurbished and it was a treat to have the whole family enjoy its site and situation. What I appreciate most is the presence of a naturalist who assists with birds and natural history. This time it was Gayomini, a young woman who is working on completing her dissertation at Colombo University. Our stay was relatively short but we visited Talimanar, Vankalai and several other places on Mannar. The Greater flamingos (Phoenicopterus roseus) were present in large numbers but at a great distance. Lenny and I went out before sunrise to try and get pictures and had reasonable success. Perhaps more importantly, we located pied avocets (Recurvirostra avosetta) -apparently some of the first sightings of the season. Ajay and other would later go on to record large flocks (40+) of this rare visitor. The other highlight of the time in Mannar was looking for saw scale vipers and frogs at night. There were large numbers of the Common Tree Frogs (Polypedates maculatus) and it was good fun photographing them with studio flashes. We returned to Colombo via Madhu and Tantirimale -our only regret was that the actual time in Mannar was unsatisfying short!

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Greater flamingos (Phoenicopterus roseus) at Mannar (December 2017).

Black-headed Gulls (Chroicocephalus ridibundus)(non-breeding plumage) at Pesalai fishing beach (northern coast of Mannar) .

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Common Tree Frogs (Polypedates maculatus) at Palmyrah House.

The Pearl Banks in the 19th Century. A two part painting from Palmyrah House.

Landsat map of the north-west coast of Sri Lanka processed by the author. Double click on image for large 150 DPI version.

PAST MANNAR POSTS

Lockwood, Ian. “A Season of Birds-Mannar.” Ian Lockwood Blog. February 2017. Web.

“     . “Mannar: Far Corner of Sri Lanka.” Ian Lockwood Blog.  November 2017. Web.

 

FURTHER READING & REFERENCES

De Silva, Anslem. Amphibians of Sri Lanka: A Photographic Guide to Common Frogs, Toad Caecilians. Published by author, 2009. Print.

De Silva, Anslem and Kanishka Ukuwela. A Naturalist’s Guide to the Reptiles of Sri Lanka. Colombo: Vijitha Yapa Publishing, 2017. Print.

Gnanam, Amrith. Discover Mannar Sri Lanka. Colombo: Palmyrah House, 2017. Print.

Kotagama, Sarath and Gamini Ratnavira. An Illustrated Guide to the Birds of Sri Lanka. Colombo: FOGSL, 2010. Print.

Warakagoda, Deepal et al. Birds of Sri Lanka. London: Christopher Helm, 2012. Print.

Bitterns in the City

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Black Bittern (Ixobrychus flavicollis) stepping out of the shadows at Nugegoda Wetland Park (17 March 2019).

During the last three months I have been making frequents visit to Colombo’s urban wetlands, looking to photograph interesting species and build enough material for an article on birding in these sometimes overlooked spots. The visits follow a pattern of exploring the urban wetlands as places for teaching and learning that highlight biodiversity and urban water issues. I started going more frequently when Colombo’s wetlands started to be better protected several years ago (see the list of past posts below).

Bitterns (Ixobrychus sp.) have been the focus of these recent efforts but I have also been looking to see and photograph other wetlands species. The article has now been completed and awaiting publication-recent tragic events in Sri Lanka have regrettably put on hold the publication. This post shares a few samples of some of the avian highlights.

There are a variety of other species that are associated with Colombo’s urban wetlands.

 

Striated heron (Butorides striata) at Nugegoda Wetland Park. (3 March 2019).

Colombo Stamen Watercolor (Ver 1 MR) 2019

Colombo’s wetlands and waterways in a map by the author.

PAST COLOMBO WETLAND POSTS

Lockwood, Ian. “Rock Star Crake at Diyasaru” 8 February 2018. Web.

”     . “Striated Heron at Beddagana.” Ian Lockwood Blog. 1 April 2018. Web.

”     . “Teaching & Learning in Colombo’s Suburban Wetlands.” Ian Lockwood Blog. October 2016. Web.

REFERENCES

“18 cities recognized for safeguarding urban wetlands.” Ramsar Secretariat. 18 October 2018. Web.

Amerasinghe , Priyanie. “What’s next now that Colombo’s an official Wetland City?” Sunday Times. 25 November 2018. Web.

Kotagama, Sarath and Gamini Ratnavira. Birds of Sri Lanka: An Illustrated Guide. Colombo: Field Ornithology Group of Sri Lanka, 2017. Print.

Ramsar. Web.

Ranasinghe, Piyumani. “Rebranding Colombo as a Wetland City.” Sunday Times. 18 November 2018. Web.

Rasmussen, Pamela C. and John Anderson. Birds of South Asia: The Ripley Guide. Volumes 1 &2, Second Edition. Washington DC: Smithsonian, 2012. Print.

Ryder, Craig. “The Growing Importance of Colombo’s Shrinking Wetlands.” Roar. 2 February 2018. Web.

Warakagoda. Deepal et. al.  Birds of Sri Lanka (Helm Field Guides). London: Helms Guides, 2012. Print.

Wijeyeratne, Gehan de Silva. A Photographic Guide to the Birds of Sri Lanka. Colombo: Vijitha Yapa Publications, 2017. Print.

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