Simpulan PROFIL OSEANOGRAFI BERDASARKAN WARNA

25 Dengan demikian, Selat Ombai juga merupakan biological hot spots di perairan nusantara karena merupakan lokasi yang secara konsisten memiliki kandungan klorofil-a tinggi dan keberadaan populasi apex predator tinggi, terutama untuk spesies Stenella longirostris, Pseudorca crassidens, dan Physeter macrocephalus yang dijumpai secara konsisten di perairan tersebut.

2.6. Simpulan

Pencitraan warna muka laut menggunakan data SeaWiFS dapat digunakan untuk menunjukkan karakteristik lingkungan fisik habitat cetacea di Selat Ombai, khususnya untuk parameter suhu permukaan laut dan kandungan klorofil-a permukaan. Profil warna muka laut yang diperoleh dari 25 peta citra SeaWiFS dapat mengidentifikasi lokasi spesifik keberadaan fitur oseanografi khusus, seperti thermal front dan eddies, yang melengkapi hasil pengamatan visual komunitas cetacea serta memberikan indikasi lanjutan terhadap kemungkinan keberadaan habitat kritis cetacea di perairan Selat Ombai, karena mayoritas titik pengamatan cetacea berada dekat dengan fitur tersebut. Konsistensi perjumpaan apex predator cetacea, keberadaan thermal front, eddies dan persistensi kondisi produktivitas primer yang tinggi berdasarkan pencitraan kandungan klorofil-a permukaan menjadikan Selat Ombai sebagai perairan biological hot spots yang penting untuk dikaji lebih lanjut. Daftar Pustaka Allen MC and A Read. 2000. 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Eds: GN di Sciara, PGH Evans, and E Politi. 8 th Bost CA, C Cotte, F Bailleul, Y Cherel, JB Charrassin, C Guinet, DG Ainley, and H Weimerskirch. 2009. The importance of oceanographic fronts to marine birds and mammals. Journal of Marine Systems 78 2009: 363-376. doi:10.1016j.jmarsys.2008.11.022 Annual Meeting of the European Cetacean Society. Montpellier, 3 March 1994. Brown CW and HE Winn. 1989. Relationship between the distribution pattern of right whales, Eubalaena glacialis, and satellite-derived sea surface thermal structure in the Great South Channel. Continental Shelf Research 9 3: 247- 260. Burtenshaw JC, EM Oleson, JA Hildebrand, MA McDonald, RK Andrew, BM Howe, and JA Mercer. 2004. Acoustic and satellite remote sensing of blue whale seasonality and habitat in the Northeast Pacific. Deep-Sea Research II 51 2004 967–986. doi:10.1016j.dsr2.2004.06.020 Cresswell G, M Purba, and SI Sachoemar. 1997. Application of remote sensing and oceanographic assessment in fisheries development. Report on short program of collaborative research. CSIRO, BPPT, and IPB. Davis RW, GS Fargon, N May, TD Leming, M Baumgartner, WE Evans, LJ Hansen, and K Mullin. 1998. Physical habitat of cetaceas along the continental slope in the north-central and western gulf of Mexico. Marine Mammal Science 14 3: 490-507. Davis RW, JG Ortega-Ortiza, CA Ribic, WE Evans, DC Biggs, PH Ressler, RB Cady, RR Lebend, KD Mullin, B Wursig. 2002. Cetacean habitat in the northern oceanic Gulf of Mexico. Deep-Sea Research I 49 2002 121–142. Doniol-Valcroze T., D. Berteaux, P. Larouche, and R. Sears. 2007. Influence of thermal fronts on habitat selection by four rorqual whale species in the Gulf of St. Lawrence. Mar Ecol Prog Ser Vol 335: 207-216. Embling CB, PG Hernandes, PS Hammond, E Armstrong, and J Gordon. 2005 Investigations into the relationship between pelagic fish and dolphin distributions off the west coast of Scotland. ICES CM2005; 15 pp. Hastie GD, B Wilson, LJ Wilson, KM Parsons, and PM Thompson. 2004. Functional mechanisms underlying cetacean distribution patterns: hotspots for bottlenose dolphins are linked to foraging. Marine Biology 2004 144: 397–403. DOI 10.1007s00227-003-1195-4 Hendiarti N. 2003: Investigations of remote sensing ocean color in Indonesian Waters. A thesis of Doctor of Philosophy, University of Rostock, Germany. 27 Kaltenberg AM. 2004. 38-kHZ ADCP Investigation of Deep Scattering Layers in Sperm Whale Habitat in the Northern Gulf of Mexico. M.Sc Thesis under supervision of DC Biggs and SF DiMarco. Major: Oceanography. Texas AM University. Lalli C and TR Parsons. 2000. Biological oceanography - an introduction. 2 nd Mann KH and JRN Lazier. 2006. Dynamics of marine ecosystems: biological- physical interactions in the oceans. 3 edition. Butterworth-Heinemann: 314 pp. rd Martin AP. 2003. Phytoplankton patchiness: the role of lateral stirring and mixing. Progress in Oceanography 57 2003 125–174. doi:10.1016S0079- 66110300085-5. ed. Blackwell Publishing: 496 pp. Moore K and M Abbott 2000. Phytoplankton chlorophyll distributions and primary production in the Southern Ocean. Journal of Geophysical Research, 105 28: 709-722. Moore TS and J Marra. 2002. Satellite observations of bloom events in the Strait of Ombai: Relationships to monsoons and ENSO. Geochem Geophys Geosyst 3 2. doi: 10.10292001GC00174. Moore SE, WA Watkins, MA Daher, JR Davies, and ME Dalheim. 2000. Blue whale habitat associations in the northwest Pacific: analyses of remotely- sensed data using Geographic Information System. Oceanography 15 3, 20-25. Nonti, A. 1993. Laut Nusantara. Penerbit Djambatan. 368 hal. Nontji, A. 2006. Tiada Kehidupan di Bumi Tanpa Keberadaan Plankton. P2O- LIPI. Jakarta. iii + 240 h. Palacios DM,SJ Bograd, DG Foley, and FB Schwing. 2006. Oceanographic characteristics of biological hot spots in the North Pacific: A remote sensing perspective. Deep-Sea Research II 53 2006 250–269. doi:10.1016j.dsr2.2006.03.004 Purba M, INMN Natih, dan AS Atmadipoera. 1994. Keterkaitan sifat-sifat oseanografi dengan sifat-sifat biologis sebagai akibat proses upwelling di perairan selatan Jawa Barat. Laporan penelitian. Fakultas Perikanan, Institut Pertanian Bogor. Robertson R and A Ffield. 2005. M2 Baroclinic tides in the Indonesian Seas. Oceanography Vol. 18, No. 4, Dec. 2005. Robertson R and A Ffield 2008: Baroclinic tides in the Indonesian Seas. Part 2: Interactions between tidal constituents, energy fluxes, and tidal mixing with a focus on Ombai Strait, doi:10.10292007JC004677. Sangra P, G Basterretxea, JL Pelegri, and J Aristegui. 2001. 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3. DINAMIKA LAPISAN PELAGIS YANG MENJADI

FORAGING HABITAT CETACEA DI SELAT OMBAI: PROFIL LAPISAN TERMOKLIN DAN HAMBUR BALIK AKUSTIK

3.1. Pendahuluan

Laut merupakan sistem yang kompleks karena dari seluruh fitur yang digunakan untuk mendefinisikan bagian atau kondisi laut, hanya batimetri yang sifatnya relatif permanen. Secara melintang, dari permukaan ke dasar, laut dikelompokkan menjadi bagian-bagian yang didasari oleh sifat penetrasi cahaya matahari, sehingga di laut pelagis dikenal zona epipelagis, mesopelagis, dan seterusnya hingga hadalpelagis Nontji 1993. Dalam ranah oseanografi, dikenal istilah lapisan termoklin yang merupakan lapisan transisi antara lapisan massa air tercampur di dekat permukaan laut dengan lapisan terstratifikasi di bawahnya, yang mengalami perubahan suhu tajam terhadap perubahan kedalaman Mann and Lazier 2006. Lebih jauh lagi, perairan pelagis ternyata memiliki beragam habitat yang tidak hanya dipengaruhi oleh faktor kedalaman dan suhu. Dipengaruhi oleh faktor dinamika oseanografi, terutama fitur khas seperti vertical mixing, eddies, front, dan internal wave, perairan pelagis dapat memiliki mikrostruktur habitat yang sangat penting dalam menyokong eskalasi produksi komunitas plankton, baik fitoplankton Martin 2003, Pershing et al. 2001, Lennert- Cody and Franks 1999 maupun zooplankton Dagg et al. 2006, Lennert-Cody and Franks 1999, Zhou et al. 1997. Pada akhirnya, perairan yang memiliki fitur khas tersebut merupakan lokasi agregasi predator di laut, seperti ikan pelagis besar, burung laut, dan cetacea Bost et al. 2009, Tynan et al. 2005, Genin 2004. Selat Ombai merupakan perairan yang mendapat pengaruh angin musim monsoon dan Arus Lintas Indonesia. Dinamika oseanografi perairan Selat Ombai juga tergolong kompleks dengan adanya batimetri yang rumit dan dalam Molcard et al. 2001, serta memiliki fenomena Ombai Jet, arus pasut ganda, internal wave, dan persistent upwelling Robertson and Ffield 2008; Moore and Marra 2003; Sprintall, pers, comm.; Robertson pers. comm.. Dalam lingkup kajian habitat cetacea di Selat Ombai, bagian tesis ini memaparkan dinamika parameter biofisik oseanografi di lapisan pelagis, terutama di lapisan epipelagis 0-200 m dan mesopelagis 200-1000 m, berdasarkan akuisisi data oseanografi pada program INSTANT.