First records of Wallace’s Hanging-parrot Loriculus flosculus from Rinca Island, Komodo National Park, Indonesia.

•Juni, 24, 2008 • Tinggalkan sebuah Komentar

First records of Wallace’s Hanging-parrot Loriculus flosculus

from Rinca Island, Komodo National Park, Indonesia.

M. JERI IMANSYAH, DENI PURWADANA and TIM S. JESSOP

A paper submitted to the Forktail

Wallace’s Hanging-parrot Loriculus flosculus is a small parrot endemic to Flores Island, East Nusa Tenggara, primarily in tropical semi-evergreen, and moist-deciduous rain forest (250–1,000 m), at the west and eastern parts of the island (BirdLife International 2003, 2004, Coates and Bishop 1997). This parrot is considered endangered because it has a small global range and probably a small population which is threatened by ongoing conversion of tropical forest habitats on Flores (BirdLife International 2003, 2004). Here we detail two independent records (in 2003 and 2006) extending its range westwards to Rinca Island, within Komodo National Park, Indonesia. Rinca Island (205 km2) is dominated by monsoon savanna (55% of land area), except in the south, which is predominantly covered by tropical dry deciduous forest. The elevation is 0–765 m. The island is separated from adjacent West Flores by a narrow strait only 400 m wide.

At 10h00 on 28 April 2003, in Loh Dasami valley (8°46¢19.9¢¢S 119°39¢15.6¢¢E; at about 10–20 m altitude), two green parrots were observed in flight below the canopy of coastal moist deciduous forest (Monk et al. 1997) area in the south of Rinca Island. The forest was dominated by Pterospermum javanicum (Sterculiaceae), a tree that can reach 25 m in height (Rudiharto 2006). The parrots were followed to a roosting tree. The birds were estimated to be c.10–12 cm in length and the predominant colour was bright green. They possessed a dark red nape, bright red rump, red uppertail-coverts, and bright red bills, confirming that these birds were Wallace’s Hanging-parrots. They were readily distinguished from the uniformly green plumage of the Rainbow Lorikeet Trichoglossus haematoduis (race weberi, endemic to Flores Island; Coates and Bishop 1997). Furthermore, we noted differences in the plumage of the two birds, with one possessing a red spot at the throat, whilst the throat of the other was entirely pale green, similar to the rest of the ventral plumage. During these initial observations both birds produced a distinct strrt strrt call. These morphological and vocal characteristics are consistent with descriptions for adult male (red spot on throat) and female (red throat spot smaller or absent) Wallace’s Hanging-parrot (Butchart et al. 1996, Coates and Bishop 1997).

We made further observations on nesting activities of an adult male and a female on 12 April 2006 (09h00–10h00 and 12h00–13h00), at the same location. The nest was situated in a tree hollow (c.10 cm wide) in a dead branch c.15 m above ground in a Terminalia catappa (Combretaceae) tree. Male and female birds were observed alternating in nest activities, and when one of them was inside the nest hollow, the other bird was waiting outside. Each bird spent c.10–15 minutes in the hollow at a time. The nest was in close proximity to several large Ficus spp. (Moraceae) trees, a known food source of this parrot (although we did not observe the birds feeding on fruit).

The closest known part of Flores Hanging-parrot’s range to our observations is the western part of Flores island which includes the areas of Golo Bilas, Wae Bobok (Nggorang Bowosie, East of Labuan Bajo), Tanjung Kerita Mese, Puarlolo, and Paku (Mbeliling forest, South of Labuan Bajo, a proposed area for protected area gazettement) (BirdLife International, 2003, 2004) (Fig. 1). Our observations extend the western extremity of the species’ range by approximately 27 km and also indicate that this parrot can utilize suitable habitat close to sea level, contrasting with observations on Flores, where records have been above 250 m in generally wetter forest types (Coates and Bishop 1997, BirdLife International 2003, 2004). Our observations suggest that it would be valuable to survey a broader range of tropical forest habitats at key sites such as Mbeliling and Nggorang Bowosie on Flores for this species, and carry out a targeted survey for this species on Rinca. Monitoring and nest surveys by Komodo National Park staff would be valuable. Our record also increases the number of parrot species inhabiting Komodo National Park to two. The other parrot species (so far recorded) is the critically endangered Yellow-crested Cockatoo Cacatua sulphurea. Komodo National Park contains the largest remaining population of the race C. s. parvula (Coates & Bishop 1997, Birdlife International 2004, Imansyah et al. 2005).

Figure 1. Recent localities for Wallace’s Hanging-parrot on Flores and Rinca island. Inset showing map of Nusa Tenggara: the arrow indicates Komodo National Park.

ACKNOWLEDGEMENTS

We thank Achmad Ariefiandy, Ibrahim Payung and Devi S. Opat for their assistance during field work. Financial support was provided by a Millennium Post Doctoral Fellowship from the Zoological Society of San Diego (ZSSD) to TSJ. Approval for the research was granted under a MOU between ZSSD and The Nature Conservancy (Indonesia Program) and by the Indonesian Department of Forest Protection and Nature Conservation (PHKA).

REFERENCES

Agista, D. and Rubyanto, D. (2001). Preliminary study on the Yellow crested Cockatoo (Cacatua sulphurea) in the Komodo National Park. Bogor, Indonesia: BirdLife Indonesia – PHPA. (In Indonesian)<!–[if supportFields]>tc “Agista, Dian; dan Dedy Rubyanto. 2001. Telaah awal status Kakatua-kecil Jambul-kuning (Cacatua sulphurea parvula) di Taman Nasional Komodo. BirdLife Indonesia – PHPA. Bogor.”<![endif]–><!–[if supportFields]><![endif]–>

BirdLife International (2003) Threatened Birds of Asia. Available from http://www.rdb.or.id/detailbird.php?id=125&sortby=latinname. Accessed on 25 April 2007.

BirdLife International (2004) Threatened Birds of the World 2004. CD-ROM. Cambridge, U.K.: BirdLife International.

Butchart, S. H. M., Brooks, T. M., Davies, C. W. N., Dharmaputra, G., Dutson, G. C. L., Lowen, J. C. and Sahu, H. (1996) The conservation status of forest birds on Flores and Sumbawa, Indonesia. Bird Conservation International 6: 335–370.

Coates, B. J. and Bishop, K. D. (1997) A guide to the birds of Wallacea. Alderley, Australia: Dove Publications.

Imansyah, M. J., Anggoro, D. G., Yangpatra, N., Hidayat, A. and Benu, Y. J. (2005) Distribution and characteristics of nesting tree of the Yellow crested Cockatoo (Cacatua sulphurea) on Komodo island in the Komodo National Park. Report of the Zoological Society of San Diego, Balai Taman Nasional Komodo, and The Nature Conservancy, Labuan Bajo, Flores. Available from http://www.komodonationalpark.org/downloads/report_cockatoo_nest.pdf. Accessed on 25 April 2007. (In Indonesian)

Monk, K. A., De Fretes Y., Reksodihardjo-Lilley, G. (1997) The ecology of Nusa Tenggara and Maluku. Singapore: Periplus Editions.

Rudiharto, H. (2006) Relationship between habitat characteristics and density of the Komodo monitor. Unpublished MSc Thesis, Gadjah Mada University,Yogyakarta.

M. Jeri Imansyah and Deni Purwandana, Center for Research of Endangered Species, the Zoological Society of San Diego, Escondido, CA, USA, and Komodo Survival Program, Denpasar, Bali, Indonesia, Email : ksp@kbproject.org

Tim S. Jessop, Center for Research of Endangered Species, the Zoological Society of San Diego, Escondido, CA, USA, and Dept. of Wildlife Conservation and Science, Zoos Victoria, Parkville, Melbourne, Victoria, Australia.


Daily activities of immature Komodo monitors Varanus komodoensis

•Juni, 18, 2008 • Tinggalkan sebuah Komentar


Daily activities of immature Komodo monitors Varanus komodoensis

M Jeri Imansyah

mjimansyah@yahoo.co.id

Method

To assess patterns in daily activities Radiotelemetry was used to observe hatchlings and the juveniles. This study was conducted between March and June over 2 years (2004-2005). Telemetry equipment consisted of activity-sensitive AVM G31V transmitters (AVM Instruments Co. Ltd.), an AVM LA12Q receiver, and a three-element Yagi antenna. Transmitters were attached to the monitor’s tail base using duct tape (Imansyah et al., 2007). After the transmitters were attached, hatchlings and juveniles were released immediately. Each animal was radio-tracked for 7 – 56 days (mean 31.42 ± 5.05 days). Initial observations showed that radio-tracked Komodo monitors never moved during the night. To increase independency of the data, individual daily observations were conducted in four sessions; separated by a minimum daily time interval of 2-3 hours. Daily positions and habitat use observations were made from 6am to 6pm across 4 time periods of morning (0600-0900h), late morning (0900-1200h), afternoon (1200-1500h) and, late afternoon (1500-1800h).

Results

Several differences were detected in daily activity patterns between hatchling and juvenile Komodo monitors. A significant difference was detected in daily activity patterns between hatchlings and juveniles. Both hatchling and juvenile Komodo monitors were tend to be less active (Chi Square χ2 = 21.26 p ≤ 0.001; T-test; t1,287 = -15.32, p ≤ 0.001 for hatchling and T-test; t1,305 = -12.35, p ≤ 0.001 for juvenile; Figure 1a), however, juveniles were more active than hatchlings (Chi Square χ2 = 28.51 p ≤ 0.001; Figure 1a).

There was a dial activity pattern displayed with two peaks of activity, first between 0900 and 1200 and the second between 1500 and 800. Hatchlings were more active in the afternoon (1500 – 1800) than juveniles were (0900 – 1200). However, juveniles also displayed their ability to be active at anytime during the day 0600 – 1800 after basking in the morning. Activity patterns were significantly differ among activity times in both hatchlings and juveniles (ANOVA F3,276 = 33.97, p ≤ 0.001 for hatchling and ANOVA F3,302 = 60.47, p ≤ 0.001 for juvenile, Figure 1b). The study reported that hatchlings mostly conducting travel between 0900 – 1200 and secondly between 15-18h but did not travel before 9h (Figure 1c). In contrary, juveniles were able to conduct traveling activity at any time even thought they were mostly conducted traveling between 9-12h (Figure 1c).

Mean daily air temperatures in Loh Liang was different among time of activities (ANOVA F3,2924 = 1624.56, p ≤ 0.001, Table 2). There was a significant correlation between daily activities and daily air temperatures (Pearson correlation test; r = 0.36, p = 0.04).

DISCUSSION

In general, both hatchlings and juveniles were less active during the study, they spent most of their diurnal periods for resting rather than for traveling or foraging and no activity were recorded during nocturnal periods. This activity pattern was similar to those reported in adult Komodo monitors by Sastrawan & Ciofi (2002). However, inactivity periods among hatchlings, juveniles and adult Komodo monitors were often followed by intense movement periods afterward (Imansyah et al., 2008; Sastrawan & Ciofi, 2002). Similar inactivity pattern was also reported in other Varanid like V gouldii and V panoptes (Christian et al., 1995) and other reptile species such as Broad-headed snake Hoplocephalus bungaroides (Webb & Shine, 2001), Brown snake Pseunaja textilis (Whitaker & Shine, 2003).

A nonuniform pattern on activity distribution was reported from this study, however, both hatchlings and juveniles displayed bimodal peak of activity time in the late morning (0900 – 1200) and late afternoon (1500- 1800). Adult Komodo monitors were also reported to have bimodal activity time in the morning (0800 – 1000) and in the late afternoon (1600 – 1800) (Sastrawan & Ciofi, 2002). Unlike hatchlings, juveniles were displayed to have ability to be active at anytime during their diurnal activity period like those reported in adults (Sastrawan & Ciofi, 2002). However, Auffenberg (1981) reported that during rainy seasons, particularly between January and March, Komodo monitors activity were more concentrated to the warmest hours. Similar to Komodo monitors, Ibrahim (2002) reported that V. griseus daily peak of activity was in the late morning (0900-1000h) and ability to be active at anytime during the day. Another monitor, V. caudolineatus, was active during late morning and early afternoon and positively correlated with the highest temperature at that time (Thompson, 1993). In contrast, Amat et al. (2003) reported that immature Lacerta agilis lizard were displayed a unimodal activity pattern that occur in the morning. As reported by (Heatwole 1976), among immature life stages it is common to have different activity cycles.

Most of hatchlings activity is carried out on tree as they displayed arboreal characteristic during this age (Imansyah et al., 2008). Arboreal character in hatchlings was believed as a mechanism to avoid predator, cannibalism, and competition among conspecific, therefore this life stage performed the least active compared to other age class (Auufenberg, 1981; Sastrawan & Ciofi, 2002). Early post natal movement in lizard is often resulting in fidelity and important to to assess resource acquisition and success in reproduction (Rose, 1981; Sumner, 2006). Further, activity and movement in immature lizards are often associated with avoidance of predatory and resource competition with adults (Auffenberg, 1981; King & Green, 1999). Webb and Shine (1997) reported that specific thermal regimes driven species to select specific retreat sites.

This study also reported influence of environment temperatures to immature Komodo monitor’s daily activities. During the study, both hatchlings and juveniles were more active in the late morning and afternoon when the average temperatures were 29.58 and 29.57 °C consecutively. Climatic and physical characteristic of environment, play a great role in influencing activity patterns in reptiles which is tend to display their favorable in particular preferred range conditions (Rose, 1981). Pianka (1986) described that reptiles are highly dependence on particular suitable temperature condition and appropriate body temperature for their activity. Although not depend on particular temperature to initiate their activity, animals have discrete times of the day in which activity is concentrated and are relate to environmental factor, i.e. temperature (Heatwole, 1976). Most lizards are changing their activity patterns in synchrony with changes in environments (Porter et al. 1973). In Whiptail lizard Aspidoscelis inornata and A. gularis initiation of daily activity has been hypothesized to be dependent upon the achievement of some critical soil temperature for lizard emergence, while cessation of activity is hypothesized to be the direct result of increasing afternoon soil temperatures that may be thermally stressful (Winne & Keck, 2004). Activity in lizards was also influenced by the intensity of solar radiation that could be a limiting factor (Christian & Weavers, 1984).

CV M Jeri Imansyah

•Juni, 6, 2008 • 1 Komentar

CURRICULUM VITAE

M Jeri Imansyah

Address : Jl Sudirman IV,Gg Karya Bhakti II no 6,

Denpasar 80234, Bali, Indonesia

Mobile :+6281338531303, E-mail :mjimansyah@yahoo.co.id

Professional Objectives

To pursue a challenging professional career in natural resource conservation or a biological field within a progressive institution that allows me to develop ideas and expertise.

Qualification summary

Ø More than six year’s professional experiences in conservation projects including research, training, campaign, and managerial oversight.

Ø Capable to be responsible for the operational/managerial oversight of project, including designing proposal and budget, undertaking activities, also monitoring and post project evaluation.

Ø Possess a considerable diligence and strong work ethic to undertake varies and often arduous conservation, research / monitoring, and training activities.

Ø Possess remarkable ability in public relations in difficult political and administrative contexts.

Ø Capable to demonstrate technical capacity to grasp and comprehend various conservation and monitoring methodologies and associated experimental design with high proficiency.

Ø Capable to organized campaign, training, and meeting events.

Ø Capable to works very well both independently and as part of a team member.

Ø Proficient in operating MS Office (e.g Words, Excell, Power Point), SPSS, Sigma Plot, ESRI ArcView, Ecological Methodology (Krebbs 1999), Fractal (Nams, 2004).

Professional experiences

Mar 2007 – Present

Komodo Survival Program, Denpasar Indonesia

Program Coordinator

Ø Responsibilities including designing and implementing activities, developing monitoring protocols for Komodo dragon and terrestrial wildlife, developing proposal and budget of related activities, managing government and stakeholders relationship in term of initiating collaborative terrestrial monitoring program in Komodo National Park and Flores, also in charge for the operational / managerial for the program.

Jun 2002 – Jul 2007

Center for Conservation and Research of Endangered Species, San Diego, USA

Research Officer / Assistant to Project Leader

Ø Responsibilities included assisting project leader in organizing and conducting programs for field research on the Komodo dragon and other terrestrial wildlife including mammals and birds. In addition, I was involved in capacity building & education, report compilation writing and translation, database and equipment management, as well as in charge as a liaison officer for CRES-ZSSD Komodo Project to undertake coordination activities with other governmental, NGO, and broadcaster institutions. In the absence of Project Leader, I was also in charge for the operational/managerial oversight of this project.

Nov 2001 – May 2002

Komodo International Research Center, Denpasar Indonesia

Research Fellow / Assistant to Project Leader

Ø Responsibilities included organizing and conducting activities for field research on hatchling of the Komodo Dragons in the Komodo National Park and report writing.


Education backgrounds

Nov 2003 – Dec 2006

Master of Science (MSc) in Zoology / Biological Conservation by thesis

Ø School of Environmental and Natural Resource Sciences, National University of Malaysia, Malaysia

Ø Thesis title “Spatial Ecology of Hatchling and Juvenile Komodo dragons (Varanus komodoensis) in the Komodo National Park, Indonesia

Ø Supervised by Prof. Dr. Zubaid Akbar (main supervisor, UKM) and Dr. Tim Jessop (co supervisor, CRES / Zoos Victoria) also reviewed by Dr Claudio Ciofi (Univ. of Florence of Italy), Dr. Joanna Sumner (Australian National University of Australia), examined by Dr. Shukor Md (UKM) and Dr (Perhilitan Malaysia)

Ø Full scholarship & research grants (USD 18,225) provided by the ZSSD and AZA

Aug 1995 – Jun 2001

Bachelor of Science (SSi) in Biology by thesis

Ø Department of Biology, Udayana University, Indonesia

Ø Undergraduate thesis title “Daily Movement and Activity of Bali Starling (Leucosar rothschildi) in the Bali Barat National Park

Ø Supervised by Sudaryanto, MS (Unud) and Ir IDPP Sastrawan, MAgrSc. (Unud)

Ø Academic Achievement Improvement Scholarship 2000-2001

Aug 1999 – Aug 2000

Diploma 1 (D1) in English

Ø LDTEC, Faculty of Letter, Udayana University, Indonesia.

Professional Developments

Ø GIS and its application for Nature Resource Management Feb 2003

BIOTROP Training and Information Center, Bogor, Indonesia.

Ø Bat Research and Conservation Training May 2003

Malaysian Bat Conservation and Research Unit, Malaysia

Ø Protected Animal Treatment Management Jul 2000

Directorate General of PHKA, Indonesian Forestry Department, Bogor

Ø ZOPP Implementation for Project Development Aug 1999

GTZ and BirdLife Indonesia, Bogor, Indonesia

Ø Environmental Impact Assessment (AMDAL A) (Third Best) Jul 1999

BAPEDAL and Udayana University, Denpasar, Indonesia

Ø Management for Non Profit Organization May 1999

BirdLife Indonesia, Bogor, Indonesia

Ø Primate Behavior and Ecology Jul-Aug 1997

Primate Research Center; Bogor Agriculture Institute, Indonesia and University of Washington, USA

Ø Advance training on First aid and SAR Management May 1996

Indonesian Red Cross Society Bali chapter

Ø Basic Training on First aid and SAR Nov 1995

Indonesian Red Cross Society Bali chapter

Research highlights (2001-present)

Ø Komodo dragon broad scale ecology : population ecology, spatial ecology, annual prey density, annual reproduction, annual recruitment, annual movement

Ø Population and ecology of Yellow-crested Cockatoo in the Komodo National Park

Ø Bird conservation in Bali and Komodo National Park

Ø Raptor Migration in Bali and Komodo National Park


Highlighted Studentship Wildlife Conservation Activities (1997-2001)

Ø Parrot trade monitoring and anti trade campaign in Bali 2000

Ø Training on Wildlife trade monitoring 2000

Ø Initiative on Green Turtle preservation and trade prohibit regulation in Bali Province 1999-2000

Ø Investigation on Java Sparrow trade in Bali 1999

Ø Green turtle trade investigation in Bali 1998-1999

Ø Bali raptor watch 1996-2001

National and International Seminar / Workshops / Internships

Ø Contributor, BirdLife International (2008) Species factsheet (Yellow-crested

Cockatoo and Flores Hanging-parrot) Nov 2007

Ø Participant, International Forestry Parallel Events on UNFCCC Dec 2007

United Nation, Ministry of Forestry of Indonesia, CIFOR, Wetland International

Ø Oral presentation, International Seminar on Biology Sept 2007

Faculty of Biology, Gadjah Mada University, Yogyakarta, Indonesia

Ø Oral presentation, National Seminar on Herpetology May 2007

Faculty of Forestry, Bogor Agricultural University, Indonesia

Ø Internship, Komodo Project May 2006

Zoos Victoria, Melbourne, Australia

Ø Visiting lecturer for Animal Behavior Class 2003; 2004; 2005

Department of Biology, Udayana University, Indonesia

Ø Volunteer, Bat Conservation and Research May 2003

Malaysian Bat Conservation and Research Unit

Ø Bali Starling preservation Jul 2001

Indonesian Ministry of Environmental

Student Supervision

Ø Marliana Chrismiawati, candidate for BSc in Forestry, Bogor Agricultural University, Indonesia (on going) 2008

Ø Makhrabi Akbar, SSi (BSc in Biology), Dept of Biology, Udayana University Bali, Indonesia 2007

Ø Rachel Rarawoda, SSi (BSc in Biology), Dept of Biology, Duta Wacana Christian University Yogyakarta, Indonesia 2007

Broadcasting / Media Consultancies

Ø Consultant, Icon Prodcutions, UK May 2008

Ø Interviewee, Mainichi Newspapers Japan May 2008

Ø Consultant, National History of New Zealand Aug 2007

Ø Consultant, National Geographic USA (Flores Python and Komodo dragon Project) Jun, Jul 2007

Ø Interviewee, Metro TV Indonesia Sep 2006

Ø Consultant, NHK Japan Aug 2006

Ø Interviewee, Kompas Indonesia Jun 2005

Ø Interviewee, Metro TV Indonesia Apr 2005

Ø Consultant, Two Hands Production, UK Mar 2005

Ø Consultant, Tigress Production UK for Discovery Channel Feb 2005

Ø Interviewee, Radio BBC UK Jul 2004

Ø Liaison officer, National Geographic USA Oct 2003

Computer Applications

Ø Softwares : Office applications, ArcView, SPSS, Ecological Methodology (Krebbs, 1999), Fractal Dimension (Nams, 2004), Macromedia Dreamweaver, Adobe Photoshops, etc.

Ø Hardwares: Computer Networking (LAN)


Scholarship & Research Grants

Ø Zoological Society of San Diego 2003-2006

Full scholarship (including tuition fees, living allowance, and travel costs) to pursue Master of Science degree in National University of Malaysia

Ø American Zoo Association 2005

Research grant (USD 3,225) for research on spatial ecology of immature Komodo dragon in the Komodo National Park

Ø Oriental Bird Club, England 2005

Conservation Grant (GBP 500) for Survey on Yellow Crested Cockatoo in the Komodo National Park

Ø Government of Bali Province, Indonesia 2001

Research grant (IDR 7.000.000) for research on Bali Starling in Bali Barat National Park

Ø Udayana University 2000-2001

Academic Achievement Improvement Scholarship (IDR 1.800.000)

Ø BirdLife Indonesia 2000

Research grant (IDR 4.000.000) fir parrot trade monitoring in Bali

Ø Yayasan Pribumi Alam Lestari

Research grant (IDR 2.000.000) for Java Sparrow trade investigation in Bali 1999

Professional Associations

Ø Member, the Center for North American Herpetology (CNAH) 2008 – present

Ø Member, International Varanid Interest Group 2007 – Present

Ø Member, Indonesian Ornithological Union (IdOU) 2005 – Present

Ø Advisory Board Member, Kokokan birdwatcher Association 2003 – Present

Ø Member, Raptor Indonesia Network (RAIN) 2002 – Present

Ø Member, Ekapaksi Alumni Volunteer for Indonesian Red Cross Society 2001 – Present

Ø Member, Earthwatch Institute Australia 2003 – 2004

Ø Coordinator, Kokokan birdwatcher Association 2000 – 2001

Ø Coordinator, NGOs Network for Bali Barat Conservation (JKBB) 1999 – 2001

Ø Representative of Kokokan for PANTAU (Wildlife trade monitoring network) 1999 – 2001

Ø Representative of HIMABIO UNUD as Member Member, Jaring PELA 1999 – 2001

Ø Member of Indonesian Wildlife trade monitoring networking (PANTAU) 1998 – 2001

Ø Chairperson, Student Association of Department Biology of Udayana University 1997 – 1998

Referees

Dr. Tim S. Jessop

- Ecologist, Department of Wildlife Conservation and Science, Zoos Victoria, Australia.

- Research Fellow (Honorary), Dept. of Zoology, University of Melbourne, Melbourne, Australia.

- Contact: ph +61 3 92859387, 92859300, fax +61 3 92859350, email tjessop@zoo.org.au

Dr. Claudio Ciofi

- Assistant Professor, Department of Animal Biology and Genetic, University of Florence, Italy.

- Komodo dragon SSP Grant Review Panel.

- Research Affiliate, Dept. of Ecology & Evolutionary Biology, Yale University, USA.

- Contact: ph +39 05 52288290, fax +39 05 52288289, email claudio.ciofi@unifi.it

Prof. Dr. Zubaid Akbar

- Professor, School of Environmental and Natural Resource Sciences, Universiti Kebangsaan Malaysia.

- Contact: ph +60 3 89213827, 89251081, email zubaid@ukm.my / zubaid@pkriscc.ukm.my

Ir. IDPP Putra Sastrawan, M.Agr.Sc

- Senior lecturer, Dept. of Biology, Udayana University, Denpasar, Indonesia.

- Contact: mobile +62 813 37762988, email iniradef@indo.net.id,.

Dr. John A Phillips

- Deputy Director, Center for Conservation and Research of Endangered Species, ZSSD, USA.

- Contact: ph +1 61 92311515, email jphillips@sandiegozoo.org.

Current Highlighted Reports, Publications, and Thesis, (published) 2003 – Jun 2008

1. Imansyah, M.J, Jessop T.S., Ciofi, C., Akbar, Z. 2008. Ontogenetic differences in the spatial ecology of immature Komodo Dragons. Journal of Zoology 274(2): 107-115.

2. Imansyah Jeri, Colin Trainor (2008) in BirdLife International Species factsheet: Loriculus flosculus. http://www.birdlife.org/datazone/species/index.html?action=SpcHTMDetails.asp&sid=1526&m=0.

3. Imansyah Jeri, Colin Trainor (2008) in BirdLife International (2008) Species factsheet: Cacatua sulphurea. http://www.birdlife.org/datazone/species/index.html?action=SpcHTMDetails.asp&sid=1398&m=0)

4. Imansyah, M.J., Purwandana, D., Jessop T.S., Ciofi, C., Akbar, Z., Ariefiandy, A., Phillips., J.A. 2007. Pergerakan dan wilayah aktivitas pada Biawak Komodo (Varanus komodoensis) di Pulau Komodo. Proceeding of National Seminar on Herpetology 2007. Bogor University of Agriculture. (in Bahasa Indonesia).

5. Jessop, T.S., Ciofi, C., Imansyah, M.J., Purwandana, D., Ariefiandy, A., Rudiharto, H. 2007. Biawak Komodo di pulau kecil lebih rentan. Warta Herpetofauna Vol I (1): 2-5, Agustus 2007. (in Bahasa Indonesia).

6. Imansyah, M.J. 2006. Spatial ecology of hatchling and juvenile Komodo dragons in the Komodo National Park, Indonesia. MSc thesis. University Kebangsaan Malaysia, Bangi. 81 p.

7. Imansyah, M.J., Anggoro, D.G., Yangpatra, N., Hidayat, A., Benu, Y.J. 2005. Sebaran dan karakteristik pohon sarang kakatua jambul kuning (Cacatua sulphurea parvula) di Pulau Komodo, Taman Nasional Komodo. Report from the Zoological Society of San Diego, Balai Taman Nasional Komodo, and The Nature Conservancy. Labuan Bajo, Flores. 30 p. (in Bahasa Indonesia).

8. Imansyah, M.J., Purwandana, D., Rudiharto, H., Jessop, T.S., 2005. Laporan no 3 rekapitulasi hasil penelitian ekologi biawak komodo (Varanus komodoensis) di taman nasional komodo 2002 – 2004. Report from the Zoological Society of San Diego, Balai Taman Nasional Komodo, and The Nature Conservancy. Labuan Bajo, Flores. 15 p. (in Bahasa Indonesia).

9. Imansyah, M.J., Purwandana, D., Rudiharto, H., Jessop, T.S. 2003. Survei Potensi Hidupan Liar Terestrial di Pulau Komodo, Taman Nasional Komodo 2002. Report from the the Zoological Society of San Diego, Balai Taman Nasional Komodo, and The Nature Conservancy. Labuan Bajo, Flores. 23 p. (in Bahasa Indonesia).

10. Imansyah, M.J., Purwandana, D., Jessop, T.S. 2002. Materi Kursus 1: Dasar-dasar Sistem Informasi Geografis untuk Staff Taman Nasional Komodo. Report from the the Zoological Society of San Diego, Balai Taman Nasional Komodo, and The Nature Conservancy. Labuan Bajo, Flores. 13 p. (in Bahasa Indonesia).

11. Jessop, T.S., Madsen, T., Ciofi, C., Imansyah, M.J., Purwandana, D., Rudiharto, H., Arifiandy, A., Phillips, J.A. 2007. Island differences in population size structure and catch per unit effort and their conservation implications for Komodo dragons. Biological Conservation 135: 247-255.

12. Jessop, T.S, Imansyah, M.J., Purwandana, D., Ariefiandy, A., Rudiharto, H., Seno, A., Opat, D.S., Noviandi, T., Payung, I., Ciofi, C. 2007. Ekologi populasi, reproduksi, dan spasial biawak Komodo (Varanus komodoensis) di Taman Nasional Komodo. Edited by Imansyah, M.J., Ariefiandy, A., Purwandana, D. The Zoological Society of San Diego, Balai Taman Nasional Komodo, and The Nature Conservancy. Labuan Bajo, Flores. 35 p. ISBN 978-979-15917-0-6. (in Bahasa Indonesia).

13. Jessop, T.S., Imansyah, M.J., Purwandana, D., Ariefiandy, A., Rudiharto, H. 2007. Panduan pemantauan ekologi di Taman Nasional Komodo, Indonesia. The Zoological Society of San Diego, Balai Taman Nasional Komodo, dan The Nature Conservancy. Labuan Bajo, Flores. 62 p. ISBN 978-979-15917-1-3. (in Bahasa Indonesia).

14. Jessop, T.S., Forsyth, D.M., Purwandana, D., Imansyah, J., Opat, D.S., McDonald-Madden, E. 2005. Monitoring the ungulate prey of Komodo dragons (Varanus komodoensis) using faecal counts. Report from the the Zoological Society of San Diego, Balai Taman Nasional Komodo, and The Nature Conservancy. Labuan Bajo, Flores, 26p.

15. Jessop T.S., Sumner J., Rudiharto H., Purwandana D., Imansyah M.J., Phillips, J.A. 2004. Distribution, use and selection of nest type by Komodo Dragons. Biological Conservation 117: 463 – 470.

Highlighted Publications in progress

1. Imansyah, M.J., Purwandana, D., Jessop T.S. 2007. First record on Flores hanging parrot Loriculus flosculus in Rinca Island, Komodo National Park. Forktail, accepted in October 2007.

2. Imansyah, M.J., Purwandana, D., Ariefiandy, A., Jessop T., Trainor, C. 2008. Current Population estimates and nest characters of the Yellow–crested Cockatoo (Cacatua sulphurea) on Komodo Island, Lesser Sundas, Indonesia. Submitted to the Bird Conservation International. (Postponed to update data of 2008).

3. Jessop, T.J., Sumner, J., Imansyah, M.J., Purwandana, D., Ariefiandy, A., Seno, A. 2007. Distribution, seasonal use, and predation of Orange-footed Scrubfowl incubation mounts on Komodo Island, Indonesia. Submitted to Journal of Field Ornithology, accepted in October 2007.

4. Schellekens, M., Trainor, C.R., Encalado, J.J.R., Imansyah, J. 2007. Status of the Pied Imperial Pigeon Ducula bicolor and Pink-necked Green Pigeon Treron vernans on Flores. Submitted to Kukila in March 2007.

Jalur Migrasi Raptor Migran Asia di Bali

•April, 3, 2008 • Tinggalkan sebuah Komentar

JALUR MIGRASI RAPTOR MIGRAN ASIA DI BALI 

M Jeri Imansyah*, Oni PB, Sudaryanto

contact : mjimansyah@yahoo.co.id

MATERI DAN METODE

Lokasi Pengamatan

Lokasi pengamatan meliputi daerah-daerah yang diperkirakan menjadi jalur migrasi, mulai dari ketinggian laut (> 0 m), hingga pengunungan (± 1500 m). Enam titik di kawasan Taman Nasional Bali Barat (TNBB), dan masing-masing satu titik di Jatiluwih, Bedugul, Tamblingan, Uluwatu, Pantai Lebih, Nusa Penida, Kintamani, Besakih, Seraya, dan Tenganan. Pemilihan berdasar penilaian secara cepat dari data sekunder dan informasi anekdotikal mengenai potensi lokasi-lokasi tersebut sebagai jalur migrasi raptor migran di Bali. Waktu pengamatan dilakukan selama bulan Oktober 2002, mulai pukul 7-17 wita. Pengamatan ini dibatasi hanya untuk mendata lokasi-lokasi yang menjadi jalur migrasi dan tempat hinggap raptor migran di Bali.

HASIL dan DISKUSI

Sebanyak 6 jenis Raptor Migran di Bali yang teridentifikasi selama periode pengamatan Oktober 2002 (Tabel 2). Jenis yang paling banyak teramati adalah Accipiter soloensis sebanyak 1567 individu yang tercatat di 7 lokasi pengamatan. Sedangkan yang paling sedikit teramati adalah Buteo buteo, sebanyak 5 individu saja yang teramati di 3 lokasi pengamatan. Sedangkan jenis raptor migran yang hanya teramati di satu lokasi adalah Accipiter trivirgatus dan Falco severus, hanya teramati di Jatiluwih. 

Tabel 1. Jenis dan jumlah raptor migran yang tercatat di Bali

Lokasi Accipiter soloensis Accipiter gularis Accipiter sp Accipiter trivirgatus Pernis ptylorhyncus Buteo buteo Falco peregrinus Unidentified
TNBB 618 38 122 0 57 1 0 220
Jatiluwih 372 0 11 22 0 0 13 36
Bedugul 3 0 0 0 0 2 0 0
Kintamani 194 1 0 0 14 0 0 2
Besakih 297 3 0 0 9 2 0 0
Seraya 76 2 97 0 0 0 0 286
Tenganan 7 0 10 0 0 0 0 56

Jalur Migrasi Raptor Migran di Bali

Sebanyak ± 2.571 individu tercatat melintas TNBB. Sementara tahun 2001 tercatat sebanyak ± 5.450 individu. Perbedaan jumlah ini kemungkinan disebabkan oleh perbedaan masa migrasi. Pada 2001 pengamatan bertepatan dengan masa puncak migrasi, hal ini juga dinyatakan oleh Wedana (komunikasi pribadi, 2001) yang melihat ribuan raptor migran dalam satu kali pengamatan di lokasi yang sama beberapa hari setelah pengamatan yang kami lakukan. Sedangkan pengamatan 2002 bertepatan dengan masa sebelum puncak migrasi. Hal ini didukung oleh Rachman (komunikasi pribadi, 2002) yang menyatakan bahwa terlihat ribuan burung migran melintas kawasan Puncak satu minggu setelah pengamatan yang kami lakukan. Pengamatan sebelumnya di TNBB mencatat 11.000 individu dalam 32 hari (Ash, 1993), 5.225 individu dalam 3 hari (Mason 1994) di bulan yang sama.

Di TNBB raptor migran tercatat masuk dari arah Barat Daya, Barat, dan Barat Laut memasuki titik pengamatan Cekik1, Cekik 2, dan Tegal Bunder. kemudian tecatat meninggalkan TNBB menuju arah Timur dari titik pengamatan Teluk Trima. Diduga raptor terbang dari arah kawasan Alas Purwo (Barat Daya), gunung Raung (Barat), dan Baluran (Barat Laut). Kelompok raptor migran yang datang dari Barat dan Barat Daya dapat termati dari Cekik 1 dan Cekik 2. Sedangkan kelompok yang datang dari arah Barat Laut dapat teramati dari Cekik 2 dan Tegal Bunder. Dari Teluk Trima raptor migran in teramati meninggalkan TNBB menuju kawasan pegunungan Pupuan yang terhubung dengan kawasan Batukaru.

Namun tercatat pula raptor migran yang memasuki TNBB dari Timur Laut Teluk Trima. Kelompok ini diperkirakan berasal dari arah Baluran, namun mereka terlebih dahulu melalui kawasan Utara Gunung Prapat Agung, kemudian setelah melewati Pulau Menjangan berbelok ke arah Teluk Trima (Barat Daya). Dari Teluk Trima kelompok ini terus terbang ke arah Tenggara seperti yang lainnya.

Di Jatiluwih tercatat ± 454 individu melintas dari arah Barat dan Barat Laut titik pengamatan. Mereka terlihat datang dari balik pegunungan Batukaru, kemudian terbang melintas menuju arah Timur dan Tenggara melintasi kawasan pegunungan di dekatnya dan daerah perkebunan dan persawahan. Berdasarkan pengamatan ini  pegunungan Batukaru dinilai berpotensi menjadi daerah bertengger bagi jenis-jenis raptor migran. Karena selama pengamatan antara pukul 8-10 pagi sekitar 200-an individu tercatat melakukan terbang berputar (soaring) di atas puncak Gunung Batukaru terlebih dahulu sebelum meluncur ke arah lain. Kemudian dari Batukaru raptor migran ini terbagi menjadi 2 kelompok. Satu kelompok melintasi Jatiluwih kemudian terbang menuju arah Timur dan satu kelompok melintasi menuju Timur Laut, melintasi Bedugul.

Sementara di titik pengamatan Bedugul hanya teramati 5 individu raptor migran yang melintas. Burung-burung inu teramati terbang dari arah Barat menuju arah Timur Laut. Sedikitnya raptor migran yang melintasi titik pengamatan ini dimungkinkan karena titik pengamatan yang kurang tepat.

Di Kintamani teramati ± 211 individu teramati terbang dari arah Barat menuju Gunung Agung, dimana Besakih terletak di Barat Daya kaki gunung ini. Di Besakih teramati sebanyak ± 311 individu, 37 individu Accipiter soloensis diantaranya tercatat bertengger di sekitar titik pengamatan Pura Gelap pada sore hari. Bahkan 3 individu Accipiter soloensis tercatat menangkap capung dan belalang di atas ladang milik penduduk setempat. Dari hasil wawancara informal, warga setempat juga menyatakan jika mereka sering melihat kelompok besar burung alap-alap yang melintas atau pun hinggap di ladang mereka dan berburu capung atau serangga lainnya pada bulan Oktober.

Dari Besakih, raptor migran terbang dalam dua kelompok. Satu kelompok teramati terbang menuju Tenggara, ke arah hutan Tenganan berada, dan satu kelompok lainnya menuju Timur, ke arah Bukit Seraya.  Dari Bukit Seraya, rombongan migrasi sebanyak ± 461 individu ini tercatat datang dari arah Barat (Besakih). Pada pagi hari raptor migran termati terbang melintas Bukit Seraya  langsung terbang menuju Timur dan diperkirakan menuju pulau Lombok. Namun setelah siang hari raptor migran terbang dan di atas Bukit Seraya berbelok menuju Barat Daya, ke arah hutan Tenganan.

Sebanyak ± 73 individu raptor migran tercatat melintas Tenganan pada sore hari. Dari titik pengamatan Bug Bug, di Timur kaki hutan Tenganan, dapat teramati datangnya kelompok raptor migran ini dari arah Barat Laut (Besakih) melintasi hutan Tenganan menuju laut lepas di sebelah Tenggara, dimungkinkan kelompok ini menuju pulau Lombok. Sedangkan kelompok lainnya teramati datang dari arah Timur Laut (Seraya) menuju Barat Daya dan diperkirakan kelompok ini hinggap di Tenganan. Namun tidak teramati raptor migran yang hinggap di kawasn Tenganan.

Berdasar jalur migrasi yang ditempuh, maka dapat diperkirakan bahwa jalur migrasi raptor migran di Bali ada yaitu; dari TNBB menuju gunung Batukaru, kemudian dari Batukaru terpecah menjadi 2 kelompok dengan arah terbang yang berbeda. Satu kelompok menuju arah Bedugul, Kintamani, dan Besakih. Sedangkan kelompok lainnya melintasi Jatiluwih menuju Besakih. Kemudian dari Besakih jalur migrasi ini kembali tebagi dua : satu kelompok menuju Seraya dan satu kelompok lainnya menuju Tenganan. Dari Seraya pada pagi hingga siang hari, raptor migran terus terbang dan diperkirakan menuju apulau Lombok. Namun setelah pukul 12 siang, raptor migran berbelok menuju Tenganan. Sedangkan dari Tenganan mereka terbang terus melintas dan diduga menuju arah pulau Lombok. Rute migrasi tersebut ditampilkan pada Gambar 1.

jalurmigrasi1.jpg

Gambar 1. Peta jalur migrasi raptor migran di Bali. Panah menunjukkan arah terbang, nomor merepresentasikan lokasi pengamatan : 1) Taman Nasional Bali Barat, 2) Jatiluwih, 3) Bedugul, 4) Kintamani, 5) Besakih, 6) Seraya, 7) Seraya, 8) Pantai Lebih, 9) Uluwatu, 10) Nusa Penida.

Lokasi Bertengger Raptor Migran di Bali

Beberapa lokasi penting yang teridentifikasi menjadi tempat bertengger adalah TNBB, Jatiluwih, dan Besakih. Berdasarkan teramatinya raptor migran yang melakukan terbang berputar (soaring) pada pagi hari (sekitar pukul 9-10 pagi) sebelum terbang ke arah lain menjadi pertimbangan memasukkan TNBB dan Jatiluwih sebagi lokasi potensial untuk lokasi bertengger. Diperkirakan lokasi bertengger di TNBB adalah di sebelah selatan Teluk Trima di deretan pegunungan Klatakan. Sedangkan di Jatiluwih diperkirakan di sebelah utara gunung Batukaru.

Lokasi yang jelas menjadi tempat bertengger adalah Besakih. Di sekitar titik pengamatan teramati puluhan Accipiter soloensis hinggap di lembah yang ada di sebelah Tenggara. Lembah tersebut berupa hutan terbuka dengan kondisi hutan yang masih cukup baik meski di sekitar lembah tersebut punggungan bukitnya telah dan sedang dikonversi menjadi ladang penduduk setempat. Beberapa penduduk setempat juga menyatakan bahwa mereka sering melihat kelompok besar burung raptor hinggap di sekitar lokasi tersebut (di ladang, ataupun hutan).

Ancaman dan Konservasi

Seperti halnya raptor jenis lain, termasuk juga raptor migran, di sepanjang jalur migrasinya di Bali jenis-jenis raptor migran yang terbang jauh dari wilayah Asia Timur in menghadapi ancaman yang cukup serius. Perubahan lahan menjadi kawasan pemukiman atau perkebunan dan ladang, mengurangi potensi tempat mereka bertengger dan mencari makan. Selain konversi habitat, ancaman lainnya adalah perburuan. Pada saat pengamatan di Pura Gelap, Besakih, tercatat 3 pemuda membawa senapan angin hendak berburu burung di kawasan tersebut. Padahal, desa adat setempat memberlakukan larangan melakukan perburuan satwa. Namun mereka tidak mempedulikan awig-awig yang seharusnya ditaati oleh seluruh penduduk desa tersebut.

Kawasan Hutan Gunung Agung sendiri dikelola oleh desa adat Keliang, Kecamatan rendang, Kabupaten Karang Asem. Kawasan ini belum memiliki status perlindungan yang ditetapkan berdasar kriteria Departemen Kehutanan. Namun desa adat setempat memiliki aturan (awig-awig) yang melarang perburuan di sekitar kawasan hutan yang disucikan tersebut.

Preliminary Population estimates of the critically endangered Yellow-crested Cockatoo Cacatua sulphurea on Komodo Island, Indonesia

•April, 1, 2008 • Tinggalkan sebuah Komentar

kakatua

Population estimates and breeding of the critically endangered Yellow-crested Cockatoo Cacatua sulphurea on Komodo Island, Lesser Sundas, Indonesia

 

M. JERI IMANSYAH, DENI PURWANDANA, ACHMAD ARIEFIANDY, Y. JACKSON BENU, TIM S. JESSOP and COLIN R. TRAINOR   

Introduction

Although the parvula race occurs on the largest islands in the Lesser Sundas, populations on Timor, Flores and Sumbawa have been decimated by captures for trade (BirdLife 2001). The single largest population is considered to persist on Komodo Island (311 km2) in Komodo National Park. Flocks of 20-30 birds were seen during brief observations from 1989 to 1995, and in 1999 an estimated 100 birds were seen by I. Mauro (BirdLife 2001). During a 30 day population count of Yellow-crested Cockatoo on Komodo in 2000, a total of 366 birds were directly observed, and a further 160 birds were estimated from unsurveyed sites (Agista and Rubyanto 2001).  Our study was done at five key valley areas, which included 320 (87%) of the Yellow-crested Cockatoo’s observed by Agista and Rubyanto (2001). The aim was to establish a new population estimate and compare with the baseline from the 2000 survey. We also noted aspects of nest biology, which may be a key aspect limiting population size (Walker et al. 2005). This study is part of conservation and research project on the Komodo Dragon Varanus komodoensis and terrestrial biodiversity in the Komodo National Park including other flagship terrestrial species, such as Timor Deer Cervus timorensis and Orange-footed Scrubfowl Megapodius reindwardt. These studies are vital to assist the Komodo National Park management to develop conservation strategies and implement site management.  

 

Method 

Komodo Island (311 km2; 8°35’40” S; 119°25’51” E, figure 1) is the largest of five major islands in the Komodo National Park that is dedicated primarily to the preservation of intact savanna landscapes, the Komodo Dragon Varanus komodoensis, and a rich and diverse marine fauna (PHKA 2000). The island has rugged topography with coastal valleys in the lowlands (below 50m) with the highest peak of is 790 m. The main habitat types on the island are savanna, open deciudous forest (tropical dry forest) and quasi cloud (or tropical evergreen) forest (Auffenberg 1981). Komodo Islands has a tropical dry climate and is influenced by monsoons and trade winds. Mean annual rainfall varies with the elevation, but averages less than 700 mm a year, with 948 mm at nearby Labuanbajo, Flores (RePPProT 1989).

This study primarily took place in the following five valleys: Loh Sebita, Loh Liang, Loh Pinda, Loh Wau, and Loh Wenci. The sites were selected because they maintain the largest Yellow-crested Cockatoo populations on the island (Agista and Rubyanto 2001).  The Yellow-crested Cockatoo population was estimated using direct counting from vantage point in each valley (Bibby et al. 2000). The census was carried out during September and October 2005 prior to the beginning of breeding season (Agista and Rubyanto 2001). Direct counting was carried out from hills, which provided observers with a suitable observation point overlooking whole valleys to allow all individuals sighted to be counted. Agista and Rubyanto (2001) used the same method in 2000. Birds were counted each morning (06h00-08h00) for three consecutive days, when they fledging from roosting sites to their feeding areas, resulting a total of three observations for each valley. The results presented within this paper are the highest counts to represent the current population of the Yellow-crested obtained during the population assessment. To assess the density of this species within each valley we divided the highest number of the birds counted by valley area.  Results During the study, 137 individuals of Yellow crested Cockatoo were counted from the five major valleys. The largest population was counted at Loh Liang (62 birds) while the lowest was at Loh Pinda (three birds) (Table 2). The overall mean density of Yellow-crested Cockatoo was 11.43±2.47 individuals km-2 (Table 2) with the highest was found in Loh Wau (18.6 km-2) and the lowest at Loh Pinda (1.67 km-2). There was a significant decline in the counts of Yellow-crested Cockatoo at the five valleys in 2005 compared with the results of the 2000 study (Table 2, Chi square test= 12.41, df = 4, p = 0.01). Population declines per valley was varied from 0-80%.  

Table 1. Past (2000) and Current (2005) population of Cacatua sulphurea on Komodo Island 

Site

Population (2000) Population (2005) Density /km-2 (2000) Density /km-2  (2005) Population decline
Loh Wenci 6 6 14.29 14.29 0%
Loh Sebita 82 50 19.20 11.71 -39%
Loh Liang 190 62 30.45 9.94 -67%
Loh Pinda 18 3 10.00 1.67 -83%
Loh Wau 44 16 51.16 18.60 -64%
Total 340 137 25.02 11.24 -60%

 

Discussion 

The current population (2005 survey) was only 137 birds, compared to the 340 birds in 2000 (Agista and Rubyanto 2001), which represents a major decline over a period of 5 years. The Yellow-crested Cockatoo population on Komodo Island is largely immune from forest loss and captures for trade, yet we report a population decline of 60% between 2000 and 2005. Our ability to interpret the cause of the decline is hampered by the general lack of ecological information on the population. For example, there is no information on the extent to which fledgling birds disperse to nearby ‘mainland’ areas such as Flores or Sumbawa, and if they do, in what numbers?; and, on such an arid island, is the availability of free water limiting during the annual dry season, following unusually dry wet seasons? Our data suggests that nest success on Komodo may be limited by a lack of nest holes. On other islands this might be caused by loss of large trees in selective logging or agriculture, but on Komodo (where large hollow bearing trees are probably naturally limited) it might be caused by older trees senescing, and regular wildfires (M. J. Imansyah, unpublished data) that might have a greater impact on mature rotten and hollow bearing trees.  Populations of the Yellow-crested Cockatoo throughout its range have been in decline since the 1970s primarily because of trapping for trade (PHPA/LIPI/BirdLife International-IP 1998; BirdLife 2001; Setiawan et al. 2001). Only on Sumba has an increased population density been reported, apparently in response to a ban on captures (Cahill et al. 2007).  Komodo Island presents a different context to the other Indonesian islands: cockatoo harvesting is effectively zero because of surveillance and enforcement (Pet and Subijanto 2001) and there is negligible loss of mature trees or forest loss through illegal logging (Pet and Subijanto 2001; Ciofi and de Boer 2004). Captures for trade and loss of mature hollow-bearing trees is undoubtedly driving the decline of other populations, but in the absence of these threats on Komodo it is unclear why the Komodo Island population may have declined.

Note: To get more evidence that yellow crested cockatoo on Komodo island is suffering a severe declines within theis last decades, thus we would like to conduct another survey in September 2008. Donation and volunteers are welcome. please contact Jeri via mjimansyah@yahoo.co.id for more detail.

Biawak Komodo di pulau kecil lebih rentan untuk punah

•Januari, 31, 2008 • Tinggalkan sebuah Komentar

 

Biawak Komodo di pulau kecil lebih rentan untuk punah.

Sebagian dari hasil proyek konservasi dan penelitian biawak Komodo di Balai Taman Nasional Komodo oleh CRES dan BTNK.

 

Dimuat di  Warta Herpetofauna Indonesia Agustus 2007 sebagai artikel

 

Tim S Jessop, Claudio Ciofi, M Jeri Imansyah, Deni Purwandana, Achmad Ariefiandy, Heru Rudiharto

 

Biawak Komodo (Varanus komodoensis Ouwen) adalah biawak terbesar di dunia (King & Green, 1999), namun sebarannya sangatlah terbatas dan hanya dapat ditemukan di lima pulau di daerah Tenggara Indonesia (Ciofi & de Boer, 2004). Selain Flores, pulau terbesar dalam cakupan wilayah sebaran biawak Komodo, empat pulau lainnya, yaitu Komodo (393.4 km2), Rinca (278.0 km2), Gili Motang (10.3 km2), dan Nusa Kode (9.3 km2), termasuk dalam wilayah pengelolaan Balai Taman Nasional Komodo (Jessop dkk., 2007a; PHKA, 2000). Bobot biawak Komodo dewasa dalam keadaan normal dapat mencapai 81.5 kg dan panjang tubuh keseluruhan dari moncong hingga ujung ekor mencapai 305 cm (Jessop dkk. unpublished data). Makanan utama Komodo dewasa adalah mamalia besar seperti Rusa Timor (Cervus timorensis), Kerbau (Bubalis bubalus) dan Babi (Sus scrofa), dengan mengandalkan strategi penyergapan dalam memburu mangsanya, sedangkan Komodo anak lebih aktif mencari untuk mendapatkan mangsanya seperti tokek pohon (Gekko gecko), telur Ayam hutan (Gallus gallus), ular, dan tikus (Auffenberg, 1981).

Ketergantungan yang cukup tinggi akan rusa sebagai makanan utamanya (>40%, Auffenberg, 1981) menyebabkan Komodo sangat rentan terhadap perubahan yang terjadi pada populasi rusa di wilayah sebaran Komodo (Ciofi & de Boer, 2004; Jessop dkk., 2006). Indeks tahunan kepadatan spesies mangsa besar untuk biawak Komodo, Rusa Timor (Cervus timorensis) mengindikasikan kecenderungan penurunan selama kurun tahun 2003-2006 (Gambar 1a). Kepadatan rusa diketahui berkaitan secara positif dengan luasan pulau, di mana pulau besar, Komodo dan Rinca, secara signifikan lebih tinggi dari pada kepadatan di pulau kecil, Nusa Kode dan Gili Motang. Indeks kepadatan rusa tertinggi tercatat di pulau Komodo, sedangkan terendah di Gili Motang (Gambar 1a; Jessop dkk., 2007a).

 

Tabel 1. Kepadatan Komodo tiap pulau di TNK

Pulau

Ukuran pulau (km2)

Kepadatan /km2

Komodo

393.4

18,82

Rinca

278.0

30,58

Gili Motang

10.3

13,38

Nusa Kode

9.3

11,80

 

komodopulaukecil1a1.jpgkomodopulaukecil1b.jpg

Gambar 1. Grafik fluktuasi indeks kepadatan tahunan rusa (a) dan korelasi kepadatan Komodo dengan indeks kepadatan rusa (b).

 

Kepadatan Komodo saat ini diketahui pada tingkat rata-rata di bawah 20 individu per km2 tiap pulaunya (Tabel 1). Secara keseluruhan, kepadatan populasi pulau tertinggi terdapat di pulau Rinca (30,58 individu/km2), sedangkan kepadatan terendah terdapat di Nusa Kode (11,80 individu/km2) (Jessop dkk. 2007a). Kepadatan biawak Komodo secara signifikan berkorelasi dengan indeks kepadatan rusa sebagai mangsa utamanya. Sebagai mangsa utama bagi komodo, kondisi populasi rusa merupakan komponen kunci yang sangat berpengaruh terhadap kondisi populasi komodo, baik secara fenotif, maupun tingkah laku (Jessop dkk., 2007b). Seiring dengan kondisi kepadatan Komodo tiap pulau yang berkorelasi dengan ukuran pulau, ukuran tubuh dan tingkah laku biawak Komodo pun nampaknya berkorelasi pula dengan ukuran pulau. Komodo di pulau besar cenderung memiliki ukuran tubuh besar dan memiliki agresivitas yang lebih tinggi, sedangkan Komodo di pulau kecil, yang memiliki ukuran tubuh relatif lebih kecil dan lebih waspada terhadap kemungkinan pemangsaan, dalam hal ini kanibalisme oleh Komodo yang lebih besar (Jessop dkk., 2007b).

            Dari keseluruhan populasi pulau biawak Komodo di TNK, nampaknya populasi di Pulau Komodo dan pulau Rinca berada dalam kondisi aman, sedangkan populasi di pulau kecil Gili Motang dan Nusa Kode menunjukkan gejala berada dalam kondisi ancaman kepunahan yang lebih tinggi dari pada populasi pulau lainnya (Jessop dkk., 2007a). Hal ini terutama ditunjukkan dengan rendahnya kepadatan populasi biawak Komodo (>15 individu/km2), juga disertai dengan rendahnya nilai indeks kepadatan rusa sebagai mangsa utama (> 10). Perbedaan jenis dan ketersediaan mangsa antar pulau, serta kompetisi intraspesifik diketahui secara jelas menjadi faktor seleksi penentu perubahan populasi dan pembentukan struktur komunitas, dan akhirnya survival spesies, dalam habitat kepulauan (Grant, 1998). Perbedaan tingkah laku kewaspadaan antar populasi pulau dapat juga mencerminkan peningkatan tekanan predasi intraspesifik (Cooper 2003; Heithaus dkk. 2002; Stone dkk. 1994). Hal ini nampak dari respon biawak Komodo di Gili Motang dan Nusa Kode yang lebih sering menghindari kehadiran manusia dari pada populasi di pulau Komodo dan Rinca (Jessop dkk., 2007c).

Dari sudut pandang manajemen, perbedaan berbagai aspek biologi dan ekologi Komodo antar pulau dapat menggambarkan adanya kebutuhan untuk mengembangankan rencana spefisik pulau yang disesuaikan dengan kondisi populasi (Jessop dkk., 2007c). Hal ini terutama penting sehubungan dengan informasi demografis jangka panjang mengenai perbedaan kondisi populasi pulau di TN Komodo, dan awal gangguan terhadap populasi-populasi ini di mana penyebaran dan imigrasi dibatasi oleh halangan lautan (Whittaker, 1998).

 

Daftar Pustaka / References:

Auffenberg, W. 1981. The Behavioral Ecology of the Komodo Monitor. Gainesville : University of Florida Press.

Ciofi, C. & de Boer, M.E. 2004. Distribution and conservation of the Komodo Monitor (Varanus komodoensis). Herpetological Journal 14: 99-107.

Cooper, W. E. Jr. 2003. Effect of risk on aspects of escape behavior by a lizard, Holbrookia propinqua, in relation to optimal escape theory. Ethology 109, 617-626.

Grant, P.R., 1998. Evolution on Islands. Oxford University Press, UK.

Heithaus, M. R., Frid, A. & Dill, L. M. 2002. Shark-inflicted injury frequencies, escape ability and habitat use of green and loggerhead turtles. Mar. Biol. 140, 229–236.

Jessop dkk. 2007a. Ekologi populasi, reproduksi, dan spasial biawak Komodo (Varanus komodoensis) di Taman Nasional Komodo. Disunting oleh Imansyah, M.J., Ariefiandy, A. dan Purwandana, D. BTNK/CRES-ZSSD/TNC.

Jessop, TS., Madsen T., Ciofi, C., Imansyah, M.J., Purwandana, D., Ariefiandy, A., Phillips, J.A. 2007b. Biawak Komodo plastis: respon predator besar terhadap pulau kecil. Terjemahan. Ariefiandy, A., Purwandana, D., Imansyah, M.J. CRES-ZSSD/BTNK/TNC. Labuan Bajo, Flores, Indonesia.

Jessop, T.S., Madsen, T., Ciofi, C., Imansyah, M.J., Purwandana, D., Rudiharto, H., Arifiandy, A., Phillips, J.A. 2007c. Island differences in population size structure and catch per unit effort and their conservation implications for Komodo dragons. Biological Conservation 135:247-255.

Jessop, T. S., Madsen, T., Sumner, J., Rudiharto, H., Phillips, J. A. and Ciofi, C. 2006. Maximum body size among insular Komodo dragon populations covaries with large prey density. _/ Oikos 112: 422_/429.

King, D.R. & Green, B. 1999. Goannas: the biology of Varanid lizards. Sydney: New South Wales Press Ltd.

PHKA. 2000. 25 years master plan for management Komodo National Park, Book 2: data and analysis. Jakarta: PHKA, The Nature Conservancy, Manggarai District Authority.

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Whittaker, R. J. 1998. Island Biogeography: Ecology, Evolution and Conservation. Oxford: Oxford Univ. Press.

 

Penulis:

Tim S Jessop1,2, Claudio Ciofi3, M Jeri Imansyah1,4*, Deni Purwandana1,4, Achmad Ariefiandy1,4, Heru Rudiharto5

 

1)  Center for Conservation and Research of Endangered Species; the Zoological Society of San Diego; San Pasqual Valley road, Escondido, CA. 92027-7000, USA.

2)  Zoos Victoria; Elliot Avenue, Parkville, Melbourne, Victoria 3052, Australia.

3)  Department of Genetic and Animal Science, University of Fiorentina, Florence, Italy

4)  Balai Taman Nasional Komodo; Jl Kasimo, Labuan Bajo, Flores, Indonesia.

5)  Komodo Species Survival Program Indonesia; Jl Sudirman IV, Gg Karya Bhakti II no 6, Denpasar 80232, Bali, Indonesia, ph 0361-7420434.

*  Kontak: komodosspi@centrin.net.id

KAJIAN EKOLOGI SPASIAL PADA SATWA LIAR

•Januari, 17, 2008 • 2 Komentar

KAJIAN EKOLOGI SPASIAL PADA SATWA LIAR

M Jeri Imansyah, Komodo Survival Program (mjimansyah@yahoo.co.id)

 

 

Hilangnya dan fragmentasi habitat saat ini merupakan ancaman paling serius bagi hidupan liar di seluruh dunia, sehingga menjadi sangat penting untuk memahami bagaimana pola dan perubahan-perubahan yang terjadi pada bentang alam serta tanggapan satwa terhadap modifikasi alam ini (Blumstein & Fernandez-Juricic 2004; Collinge 2001). Proses spasial yang heterogen berpengaruh langsung terhadap system ekologi (Gardner et al. 1998). Pengaturan spasial individu-individu dalam populasi akan merefleksikan aspek-aspek tingkah laku dan ekologinya, dan ini penting dalam menentukan keberadaan populasi dan lairan gen di dalam dan antar sub populasi (Brown & Downhowe 1988: Johnson 2000). Sehingga, dinamika populasi satwa tidak hanya tergantung pada laju kelahiran dan kematian semata, tapi juga terhadap kemampuan satwa untuk bergerak masuk atau keluat populasi (Dasmann 1964). Menentukan jumlah individu yang terdapat di suatu wilayah adalah merupakan pertanyaan paling mendasar dalam ekologi, tapi lebih penting lagi untuk dapat memahami bagaimana satwa memberikan respon terhadap perubahan kondisi bentang alam, terlepas ini berada pada tingkat individu, populasi, atau pun komunitas (Lawson et al. 2006).

 

Ekologi spasial menurut merupakan inti dari sain ekologi. menunjukkan bahwa ekologi spasial adalah sain yang salah satu tujuannya adalah untuk dapat mengerti proses-proses ekologi yang mempengaruhi sebaran individu yang biasanya jarang tersebar secara merata meliputi keseluruhan bentang alam (Boyce & McDonald 1999; Krebs (1999). Coliinge (2001) menyimpulkan bagwa ekologi spasial adalah merupakan kajian studi yang dipusatkan untuk dapat memahami bagaimana konfigurasi bentang lahan berpengaruh terhadap dinamika populasi dan komunitas suatu organisme. Sedangkan Whitaker dan Shine (2003) menyatakan bahwa dengan mempelajari ekologi spasial dapat memberikan kontribusi paling tidak terhadap tidak keuntungan, yaitu : satu, pemahaman yang lebih baik tentang pergerakan dan pemilihan habitat oleh satwa; kedua, memberikan informasi tentang interaksi satw-manuia; dan ketiga, sebagai suatu alat untuk menilai respon dan peran satwa di dalam habitatnya. Dalam hal ini Collinge (2001) menekankan bahwa studi empiris dalam ekologi spasial sangat menunjang penelitian untuk keperluan konservasi sebagai mekanisme praktis untuk desain rencana pengelolaan dan konservasi hidupan liar. Dalam melakukan kajian ekologi spasial, kebanyakan peneliti memasukkan kajian dispersal (Olsson & Shine 2003), pergerakan dan wilayah aktivitas atau wilayah jelajah, penggunaan habitat, pola aktivitas (Fitzgerald et al. 2002; Piepgras & Lang 2000); jenis makanan (Thompson & Thompson 2001; Whitaker & Shine 2003); dan perubahan habitat (Pearson et al. 2005; Fitzgerald et al. 2002).

 

Dapat disimpulkan bahwa kajian ekologi spasial dapat meliputi dispersal, pergerakan dan wilayah aktivitas atau wilayah jelajah, penggunaan habitat, pola aktivitas jenis-jenis makanan sebagai respon organisme terhadap kondisi dan perubahan habitat.

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