A NEW SPECIES OF WATER SNAKE GENUS HYPSISCOPUS (SERPENTES: HOMALOPSIDAE) FROM SULAWESI, INDONESIA

We describe a new species of water snake genus Hypsiscopus that was formerly placed in the genus Enhydris from Towuti Lake, South Sulawesi, based on six specimens collected in 2003 and a specimen collected in 2019. The new species has several significant differences from other species in the genus Hypsiscopus (H. matannensis, H. plumbea, and H. murphyi) in possessing laterally compressed tail, higher number of scale rows in mid body, higher number of ventral scales, lower number of subcaudal scales, and distinct color pattern. The new species is likely distributed only in the Towuti Lake, and has higher level endemicity compared to H. matannensis. Further studies on the population and distribution are needed to evaluate its conservation status

Modified Convective Stratiform Technique (CSTm) Performance on Rainfall Estimation in Indonesia

This study has analyzed a rainfall estimation using a modified convective stratiform technique (CSTm). Unlike the original convective stratiform technique (CST), which only utilizes infrared (IR) data, CSTm applies not only IR data but also passive microwave (PMW) data. Two major modifications contained in CSTm are: (1) the application of a variability index (VI) method that uses PMW data to perform convective and stratiform separation,and (2) the ability to determine the average extensive coverage of the new areas of each pixel point as a result of the utilization of the PMW data. In this study, rainfall estimation was conducted for 23 points spread over four major islands in Indonesia. The estimation was performed based only on IR and PMW data obtained from coincident observations. For verification, the estimation results were compared with real observations. The main verification action conducted in this study used multi-category contingency tables for four categories and this action was supported by the root mean square error (RMSE)method.The verification results of the hourly estimation conducted for 4 days in early November 2011 showed that CSTm can effectively improve the performance quality of CST

Studi Pendahuluan : Keberadaan Kura-kura Rote (Chelodina Mccordi, Rhodin 1994) Di Pulau Rote, Nusa Tenggara Timur

A preliminary to investigate the remaining population of Rote snake-necked turtle Chelodina mccordi in Rote Island, Nusa Tenggara Timur was conducted in 20th of May – 25 th of June 2005. Based on previously known turtle distribution and interviews with local people, we surveyed 105 locations in Rote Island. We found 35 locations in Rote island suitable for turtle habitat, in which based on interviews 26 locations were previosly known as turtle habitats but no turtles were found anymore during the last few years, and nine locations where turtles are still occasionally seen. Our survey yielded no sighting of terrapin, we only found one snake-necked turtles brought by harvester from Peto marsh. Threats to Rote snake-necked turtles are hunting, loss of habitat to agricultural conversion and polution from agricultural land, and grazing by herds. More survey need to be carried out, especially during rainy season where there are more possibility of finding this turtle

STUDI PENDAHULUAN : KEBERADAAN KURA-KURA ROTE (Chelodina mccordi, Rhodin 1994) DI PULAU ROTE, NUSA TENGGARA TIMUR

A preliminary to investigate the remaining population of Rote snake-necked turtle Chelodina mccordi in Rote Island, Nusa Tenggara Timur was conducted in 20th of May – 25 th of June 2005. Based on previously known turtle distribution and interviews with local people, we surveyed 105 locations in Rote Island. We found 35 locations in Rote island suitable for turtle habitat, in which based on interviews 26 locations were previosly known as turtle habitats but no turtles were found anymore during the last few years, and nine locations where turtles are still occasionally seen. Our survey yielded no sighting of terrapin, we only found one snake-necked turtles brought by harvester from Peto marsh. Threats to Rote snake-necked turtles are hunting, loss of habitat to agricultural conversion and polution from agricultural land, and grazing by herds. More survey need to be carried out, especially during rainy season where there are more possibility of finding this turtle.Keywords: Rote, turtle, habitat, conservation, Indonesia; Chelodina mccord

DETEKSI POTENSI GERAK VERTIKAL ATMOSFER DI ATAS WILAYAH BANDUNG DAN SEKITARNYA

Pada penelitian ini deteksi potensi gerak vertikal atmosfer di atas wilayah Bandung dan sekitarnya telah dicoba dilakukan. Upaya untuk mendeteksi potensi keberadaannya dilakukan dengan memanfaatkan terdapatnya konvergensi atau pengaruh kondisi orografi yang menjadi salah satu sebab dari timbulnya gerak vertikal tersebut. Melalui upaya interpolasi data angin pada arah horisontal (2D) di beberapa ketinggian yang berbeda untuk 9 waktu pengamatan pada bulan Oktober 2003, dilakukan analisis hodograf untuk menentukan indikasi kemampuan olahan data angin dalam mendeteksi potensi gerak vertikal, analisis divergensi untuk mengetahui terdapatnya konvergensi serta analisis vortisitas relatif untuk mengetahui terdapatnya pengaruh kondisi orografi. Setelah melalui analisis hodograph, hasil dari analisis divergensi dan vortisitas relatif selanjutnya dibandingkan dengan kondisi awan yang terjadi yang ditunjukkan oleh data MT-SAT kanal inframerah sebagai representasi akibat  adanya gerak vertikal.  Berdasarkan perbandingan kedua analisis tersebut  menunjukkan bahwa analisis vortisitas relatif dapat mendeteksi adanya potensi gerak vertikal  di atas wilayah penelitian  dengan cukup signifikan sedangkan analisis divergensi  sebaliknya. Hal tersebut menunjukkan bahwa gerak vertikal yang terjadi lebih didominasi oleh pengaruh kondisi orografi.  Tingkat korelasi rata-rata deteksi potensi gerak vertikal yang diperoleh melalui analisis vortisitas relatif adalah 64 % dan hal tersebut sekaligus juga menunjukkan bahwa olahan data angin yang digunakan dapat berfungsi dengan cukup baik.   An attempt to detection the atmosphere vertical motion potency on Bandung and its around as the investigation area has been carried out. The investigation was done by utilize the convergence or orographic influences that caused the vertical motion. The wind data in regular points was found by horizontal interpolation of wind observation that observed in some places for 9 observation time in October 2003 as the first step and then was done the hodograph analysis to determine the ability of horizontal interpolation result to detection vertical motion potency, divergence analysis to detection the convergence and relative vorticity analysis analisis to detection the orographic influences. Base on the comparing of divergence and relative vorticity analysis with the MT-SAT data, they show the relative vorticity analysis can detect vertical motion potency on investigation area with significantly result whereas the divergence analysis is the opposite. This result gives indication that the vertical motion on the investigation area more dominated by orographic influences as the main cause.  Finally, the mean accuracy of detection vertical motion potency by relative vorticity analysis is 64 % and this result also show that the wind data in regular points by interpolation can be used well

PEMANFAATAN DATA GELOMBANG MIKRO PASIF DAN INFRAMERAH DALAM PEMISAHAN BUTIRAN AWAN KONVEKTIF DAN STRATIFORM

Di wilayah tropis, jenis awan dapat dibagi  atau dipisahkan menjadi 2 kelompok yakni konvektif dan stratiform.  Pada penelitian ini dilakukan pemisahan dengan menggunakan 3 metode pemisahan yakni Convective Stratiform Technique (CST), Variability Index (VI) dan Window Channel Difference (WCD). Ketiga metode tersebut memanfaatkan data satelit cuaca baik satelit gelombang mikro pasif maupun inframerah sebagai masukan utamanya. Verifikasi menggunakan metode tabel kontingensi dari ketiga metode tersebut dilakukan dengan menggunakan data radar cuaca. Penggunaan data radar cuaca sebagai pembanding didasarkan atas kemampuan data radar yang lebih baik dari satelit dalam mendeteksi kondisi hidrometeor. Penelitian dilakukan di wilayah Jawa Barat, Banten dan DKI Jakarta untuk tujuh hari pengamatan yang dilaksanakan pada awal Januari 2010. Selama tujuh hari pengamatan diperoleh 180 titik yang bersesuaian waktu dan posisi antara data satelit dan radar. Berdasarkan hasil verifikasi di 180 titik tersebut diketahui bahwa metode CST adalah metode terbaik untuk  melakukan pemisahan yang selanjutnya diikuti oleh VI dan terakhir WCD.   Separation of 2 main groups of tropical rainfall namely convective and stratiform was conducted in this research. There are 3 methods of separation i.e. Convective Stratiform Technique (CST), Variability Index (VI) and Window Channel Difference (WCD). These methods utilized the passive microwave and infrared weather satellite data. Verification using contingency table method of separation results from those methods has also been done in this research to assess the quality of separation. To verify the separation results, the same methods were applied to radar data. Utilization of radar data for verification was considered due to its ability on observing the hydrometeor which is more sensitive than satellite. From seven observation days in early January 2010 there were found 180 points with appropriate position and time among passive microwave satellite, infrared satellite and radar in West Java, Banten and Jakarta area. Based on the verification results at those points, the CST give the best outcome, followed by VI and WCD

ANALISIS INTENSITAS CURAH HUJAN WILAYAH BANDUNG PADA AWAL 2010

Pada awal 2010 di wilayah Bandung telah terjadi hujan dengan intensitas yang sangat tinggi serta berlangsung dalam waktu yang cukup lama. Kondisi ini telah mengakibatkan kerugian materil dan immateril akibat terjadinya beberapa bencana seperti banjir, tanah longsor, serta meluapnya bendungan. Berdasarkan hasil analisis intensitas curah hujan diketahui bahwa jumlah curah hujan yang terjadi pada bulan Januari, Pebruari dan Maret 2010, seluruhnya berada di atas normal demikian pula dengan jumlah hari hujannya. Tingginya intensitas curah hujan yang terjadi selama 3 bulan berturut-turut dengan kondisi di atas normal jarang sekali terjadi di wilayah Bandung. Berdasarkan catatan yang dimiliki oleh BMKG Stasiun Geofisika Bandung hal serupa pernah terjadi pada tahun 1952 dan 1966, namun demikian intensitas curah hujan bulanan yang terjadi pada awal 2010 tersebut  yang terjadi selama 3 bulan berturut-turut merupakan yang tertinggi dari yang sebelumnya pernah terjadi.   In Early 2010 occurred rainfall with very high intensity and long duration in Bandung and its surrounding. This condition has caused material and immaterial losses caused by floods, landslides and overflow of dam. Based on analysis, it is known that the rainfall intensity in January, February, and March 2010, was above normal as well as the total rainfall days. These conditions are very rare in Bandung. Based on BMKG's record, conditions such that occurred in 1952 and 1966, however the rainfall intensity in the early 2010 was the highest

PENENTUAN NILAI AMBANG VARIABILITY INDEX (VI) SERTA NILAI INTENSITAS CURAH HUJAN OPTIMAL DALAM MELAKUKAN ESTIMASI CURAH HUJAN DI INDONESIA MENGGUNAKAN METODE CONVECTIVE STRATIFORM TECHNIQUE HASIL MODIFIKASI (CSTm)

Penentuan nilai ambang dari metode Variability Index (VI) yang digunakan dalam melakukan separasi konvektif dan stratiform serta penentuan nilai intensitas curah hujan optimal baik untuk konvektif maupun stratiform guna menentukan estimasi curah hujan di Indonesia dilakukan pada penelitian ini. Dengan melakukan perubahan terhadap nilai ambang yang telah ada sebelumnya serta pengujian terhadap tingkat akurasi yang dapat diperoleh sebagai dampak dari perubahan tersebut maka nilai ambang baru yang dapat digunakan untuk melakukan separasi konvektif dan stratiform di Indonesia dapat ditentukan. Demikian pula untuk intensitas curah hujan konvektif, dengan mempertimbangkan nilai simpangan rata-rata terkecil terhadap kondisi riilnya dari hasil estimasi curah hujan yang seluruhnya dianggap konvektif, maka nilai optimal dari intensitas curah hujan konvektif di Indonesia dapat diketahui. Dengan memanfaatkan nilai ambang serta nilai intensitas konvektif yang telah ditentukan lebih dahulu, nilai intensitas curah hujan stratiform dapat ditentukan melalui pemanfaatan variasi nilai yang mungkin digunakan  dikaitkan dengan perolehan tingkat akurasi yang dapat diperoleh. Khusus untuk penentuan intensitas curah hujan konvektif dan stratiform, berbagai pendapat para peneliti sebelumnya juga digunakan sebagai dasar pertimbangan. Terakhir, hasil dari penelitian ini menunjukkan bahwa nilai optimal yang diperoleh untuk nilai ambang VI adalah 14, adapun intensitas curah hujan konvektif dan stratiform masing-masing adalah 26 mm jam-1 dan 0,8 mm jam-1.   Determination of new Variability Index (VI) threshold and optimal convective and stratiform rain rates were carried out in this research. By making changes to the existing threshold in the rainfall estimation process and in the accuracy test of estimation results, the new threshold value of VI can be determined. Likewise, by considering the smallest value of average deviation against the observation results, the convective rain rate can be determined. Both VI threshold and convective rain rate results could then be utilized for the determination of the stratiform rain rate by acquisitioning  the accuracy value using the possible value of variation rain rate.  Results of previous studies also is taken intoconsideration in determining the convective and stratiform rain rate . Concusively, the results of this research shows that the optimal value of VI is 14, whilst the convective rain rate is 26 mm h-1 and stratiform rain rate  is 0.8 mm h-1. Thus, these results can be used in modification of Convective and Stratiform Technique (CSTm) to estimate the rainfall in Indonesia with better estimation

Chytridiomycosis in frogs of Mount Gede-Pangrango, Indonesia

Batrachochytrium dendrobatidis (Bd) is a fungus recognised as one of the causes of global amphibian population declines. To assess its occurrence, we conducted PCR diagnostic assays of 147 swab samples, from 13 species of frogs from Mount Gede Pangrango National Park, Indonesia. Four swab samples, from Rhacophorus javanus, Rana chalconota, Leptobrachium hasseltii and Limnonectes microdiscus, were positive for Bd and had low to moderate levels of infection. The sample from L. hasseltii was from a tadpole with mouthpart deformities and infection was confirmed by histology and immunohistochemistry. An additional sample from Leptophryne cruentata showed a very low level of infection (≤1 zoospore equivalent). This is the first record of Bd in Indonesia and in Southeast Asia, dramatically extending the global distribution of Bd, with important consequences for international amphibian disease control, conservation and trade. Consistent with declines in amphibian populations caused by Bd in other parts of the world, evidence exists for the decline and possible extirpation of amphibian populations at high elevations and some decline with recovery of populations at lower elevations on this mountain. Therefore, it is essential to manage Bd in Indonesia where it is likely to be threatening amphibian populations. This will require a national strategy to mitigate the spread of Bd in Indonesia and neighboring countries as well as the impact of that spread. It is also important to collect information on the extent of the impact of Bd on frog populations in Indonesia

Predation threats to the Red-billed Tropicbird breeding colony of Saba: focus on cats

Feral domestic cats (Felis catus) are recognized as one of the most devastating alien predator species in the world and are a major threat to nesting colonies of the Red-billed Tropicbird (Phaethon aethereus), on Saba island, Dutch Caribbean. Cats and rats are both known to impact nesting seabirds and hence are both potential threats to the tropicbird on Saba. However, whereas the tropicbird has coexisted with rats for centuries, cats have only recently become a problem (since about 2000). Several studies from the region suggest that the tropicbird may be less-vulnerable to rats but cats have been unequivocally implicated in the depredation of tropicbird nests on Saba (unpublished data, Michiel Boeken). In this study we collected baseline data on cat and rat distribution, and cat diet and health. We also conducted 83 questionnaire interviews with Saba residents to assess their views on cats, rats, tropicbirds and the acceptability of different management options