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Abstract. Wijaya A, Zakiyah U, Sambah AB, Setyohadi D. 2020. Spatio-temporal variability of temperature and chlorophyll-a concentration of sea surface in Bali Strait, Indonesia. Biodiversitas 21: 5283-5290. The Bali Strait is influenced by seasonal and inter-annual systems. El Nino-Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) are climate variabilities that affect water conditions. The knowledge about influence of ENSO and IOD variations on the fertility of waters in the Bali Strait is still lacking. The purpose of this study was to determine the effect of seasonal and inter-annual variability on the variability of Sea Surface Temperature (SST) and Sea Surface Chlorophyll-a (SSC) in the Bali Strait. This study applied SST and SSC data collected from the Aqua/Terra MODIS satellite, as well as the ENSO and IOD indices during March 2000-December 2019. The results described that the effect of ENSO on SST and SSC was low and IOD on SST and SSC was quite high. The effect was quite high between IOD and SST anomaly of-0.401. Seasonal variations indicate the abundance of high SSC and low SST in the southeast monsoon (JJA) which characterizes upwelling. Meanwhile, in the northwest monsoon (DJF), SSC was low and SST was high which characterizes downwelling. This condition cannot separate from the monsoonal process that occurred in the Bali Strait. The inter-annual variation showed that in the strong El Nino period and IOD (+) triggers a negative SST anomaly and a positive SSC results in strong upwelling, while in the strong La Nina period and strong IOD (-) triggers a positive SST anomaly and a negative SSC results in downwelling. The inter-annual variability of SSC influenced by IOD rather than ENSO. This condition indicates that the ENSO/IOD event changes the period of SSC concentration.

ABSTRAKPulau Sempu adalah satu-satunya cagar alam yang berada di Kabupaten Malang yang memiliki terumbu karang dengan luasan kurang dari 10 ha yang mampu bertahan dari banyaknya ancaman yang berpotensi merusaknya. Faktor lingkungan secara alamiah telah menyeleksi keanekaragaman diwilayah perairan P. Sempu, yakni hanya 9 life form karang keras yang berperan sebagai penyangga ekosistem terumbu karang di wilayah ini. Mengetahui distribusi ukuran koloni karang sama pentingnya mengetahui umur koloni karang keras untuk melihat kondisi ekosistem terumbu karang pada suatu perairan. Klas frekuensi koloni karang keras akan memberikan informasi mengenai kemampuan kompetisi, masa pubersitas dan tentu kemampuan regenerasi. Pengambilan data luasan karang dilakukan di 4 stasium (Watu Mejo 1, Watu Mejo 2, Teluk Semut 1 dan Teluk Semut 2) menggunakan kuadrat transek 1 x 1 m sepanjang 50 m pada kedalaman 5m. Berdasarkan penelitian didapatkan luasan total tertinggi pada Acropora Branching (ACB) adalah 145.811,67 cm 2 dan terenda pada karang jamur (CMR) 414,35 cm 2 . Life form karang dapat dijadikan rujukan awal menilai kesehatan ekosistem terumbu karang. Dominan karang dengan life form massive dapat diartikan kawasan tersebut memiliki kondisi lingkungan yang penuh tekanan semisal sedimentasi tinggi, arus kuat maupun sering terekspos udara. Ukuran karang di P. Sempu rerata menunjukkan > 5 cm 2 yang berarti sudah dewasa dan mampu melakukan reproduksi, sedangkan rekruitmen sangat rendah dengan indikasi sedikitnya jumlah luasan karang kurang dari 4 cm 2 .Kata kunci: cagar alam, bentuk pertumbuhan, reproduksi, konservasi, karang keras ABSTRACTThe abundance of coral reef in Sempu Island nature reserve was under 10 ha, in which they were a winner from environment and human threats. The environment has big role to select scleractinian coral in this area that resulted 9 coral life form as the main foundation of coral reef in Sempu nature reserve area. Knowing the coral size distribution as important to know of coral age in term determining the health of coral reef ecosystem. Class frequency of colony size gave the key information of coral competition, puberty and regeneration ability. We choose 4 station (Watu Mejo 1, Watu Mejo 2, Teluk Semut 1 dan Teluk Semut 2) to take data. Data colony size was taken by 1 x1 m quadrat along 50 m in 5 m depth. The highest colony size was Acropora branching (ACB) about 145,811.67 cm 2 and the lowest one was mushroom coral (CMR) about 414.35 cm 2 . Life form of coral can be early detection of coral reef health. Dominance of massive coral means the coral reef under the high sedimentation, strong current or exposed by air frequently. The coral colony size in Sempu nature reserve showed > 5 cm 2 that indicate they were in maturity and have capability for reproduction but the coral recruitment was very low due to few number of coral has less than 4 cm 2 in colony size.

<p>ABSTRACT<br />The Banggai Cardinalfish (Pterapogon kauderni) or capungan Banggai (often abbreviated as BCF) is a marine fish endemic to the waters around the Banggai Archipelago, caught in large numbers for the marine aquarium trade. The conservation of this endemic species became an international issue, in 2007 the BCF was proposed for CITES listing by the USA and listed as Endangered in the IUCN Red List. The CITES proposal was withdrawn, with Indonesia committed to conserve the Banggai Cardinalfish through a sustainable ornamental fishery approach. The multi-stakeholder Banggai Cardinalfish Action Plan (2007-2012) and other initiatives have aimed towards this goal; however the initiative to secure limited protected status in 2011 failed. Studies during 2011-2012 found many positive developments in the BCF fishery, and if the carrying capacity (stocks and ecosystems) was similar to the early 2000’s, current official exploitation levels should be sustainable. However a stock assessment analysis using FISAT II revealed a high exploitation level (0.5), indicating catches may have reached or possibly exceeded sustainable limits. Survey/monitoring results indicate the endemic population is not in a steady state, with sharp declines in the past decade. There are strong indications that habitat degradation is the main cause of this decline, including over-exploitation of key BCF micro-habitat (sea urchins and sea anemones). Without an effective solution to protect the supporting ecosystem, P. Kauderni will be increasingly threatened with extinction, with or without fishing pressure. The case of the BCF highlights the importance of an ecosystem-based approach to fisheries policy and management.<br />Key words: ecosystem-based approach to fisheries management, Pterapogon kauderni, stock<br />assessment, sustainable ornamental fishery</p><p>-------</p><p><br />ABSTRAK<br />Banggai cardinalfish (Pterapogon kauderni) yang sering disingkat BCF atau capungan Banggai merupakan ikan laut endemik di perairan Banggai Kepulauan dan sekitarnya yang ditangkap dalam jumlah besar untuk diperdagangkan sebagai ikan hias. Kelestarian spesies endemik tersebut menjadi isu internasional dan pada tahun 2007 diusulkan pada CITES oleh Amerika Serikat dan didaftarkan sebagai Endangered pada Red List IUCN. Status terdaftar pada CITES ditangguhkan, namun Indonesia berkomitmen untuk menjamin kelestarian Banggai cardinalfish dengan pola sustainable ornamental fishery. Rencana Aksi Banggai Cardinalfish multi-stakeholder (2007-2012) dan beberapa inisiatif lain bertujuan mewujudkan tujuan tersebut antara lain penetapan status jenis lindung terbatas, namun upaya yang diinisiasi pada tahun 2011 tersebut gagal. Berdasarkan data kajian 2011-2012, banyak perubahan positif dalam perikanan BCF, dan jika daya dukung alam (stok dan ekosistem) masih seperti pada awal tahun 2000-an tingkat pemanfaatan resmi seharusnya sustainable. Hasil kajian menggunakan FISAT II bahwa tingkat pemanfaatan (0,5) tergolong tinggi, dan merupakan indikasi bahwa tingkat pemanfaatan telah pada atau melebihi batas maksimal lestari. Hasil survey/monitoring menunjukkan bahwa populasi endemik tidak pada kondisi steady state dan menunjukkan penurunan tajam dalam dekade terakhir. Terindikasi kuat bahwa penyebab utama penurunan tersebut adalah degradasi habitat, antara lain akibat pemanfaatan lebih mikrohabitat (bulu babi dan anemon laut). Tanpa solusi efektif untuk melestarikan ekosistem pendukung, P. kauderni akan semakin terancam punah, dengan atau tanpa adanya penangkapan. Kasus BCF menunjukkan pentingya pendekatan ecosystem-based approach terhadap kebijakan dan manajemen perikanan tangkap.</p><p><br />Kata kunci: ecosystem-based approach to fisheries management, Pterapogon kauderni,<br />pengkajian stok, sustainable ornamental fishery</p>

This study aims to find scientific data concerning distribution pattern of R. argyrotaenia, catch composition of R. argyrotaenia including length frequency data, fishing peak season, spawning season, and abiotic characteristics of aquatic environment, such as life of R. argyrotaenia. The findings indicate that distribution pattern of R. argyrotaenia during rainy season (January-April) is scattered in main river, tributary, and marsh (flood plain), during dry season (May-August), position of fish is in main river and tributary, while in transitional months (September-December), fish is concentrated in main river. Fishing peak season occurs in April, May, June, and July reaching average haul range of 9.98 kg/month + 0.62-12.63 kg/month + 1.08. Based on Analysis of Progression Model by utilizing FISAT II on length-based data of R. argyrotaenia, there found three cohorts by average length of 65.76 ISSN 2157-6092 2014 www.macrothink.org/jee 118 mm + 9.0, 116.13 mm + 15.0, and 156.63 mm + 4.7. Referred to analysis of the Von Bartalanffy growth curve, it is known that inital spawning season of R. argyrotaenia alleged that the peak spawning season occurs in September, October, November and December reaching value of Linf=173.25, K=0.510/year, and t0=0.02. R. argyrotaenia lives in habitat where average temperature is 25.5 oC + 0.12 -31.6 oC + 0.12, current speed of 0.06 ms-1+ 0.02 -0.27ms-1 + 0.02, pH of 4.23 + 0.03 -6.74 + 0.05, and DO of 4.2 mg l-1 + 0.06 -7.5 mg l-1 + 0.10. Journal of Environment and Ecology

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The Banggai cardinalfish (Pterapogon kauderni, Koumans 1933), often referred to as BCF, is a restricted range coral reef associated fish endemic to shallow waters (0-5m) around the Banggai Archipelago, Indonesia. Listed as "Endangered" in the IUCN Red-List, the international marine aquarium trade and habitat degradation are considered major threats. After the (unsuccessful) proposal for listing under CITES Appendix II in 2007, a national BCF Action Plan was developed. A District MPA was established by decree of the Banggai Kepulauan District Head, consisting of a network of 10 islands. For 2 of these P. kauderni conservation is the main management target. With no pelagic phase and high site fidelity, the Banggai cardinalfish population exhibits a level of genetic structure unusual in a marine fish. Several genetically distinct sub-populations have been identified, indicating that management units should be based on genetically determined sub-populations (stocks). Using available genetic and biogeographical data, the MPA network can be examined from the viewpoint of P. kauderni genetic diversity conservation, and critical knowledge gaps identified. A research programme is necessary for the identification of these units and the characterisation of each unit from biological (including genetic), ecological (e.g. habitat/micro-habitat) and socio-economic (including fishing ground) aspects. The data would be managed within a GIS database and spatial analysis tools such as MARXAN used to provide management support. In particular, science-based zoning options with management units/targets based on genetic population structure and the ability to evaluate the conservation effectiveness of options put forward by stakeholders.

Fringescale sardine (Sardinella fimbriata) is small pelagic fish that has an increasing production every year. This can trigger the occurrence of overfishing, so it is necessary to study the biology and dynamic population of fish. This research was conducted in December 2016 -May 2017. The purpose of this research was to determine the biological aspects and population dynamic of fringescale sardine (S. fimbriata) in Bali Strait. Samples were obtained from surface gillnet landed in Muncar fishing port, with 1471 of fish. Results showed that sex ratio was about balanced with the proportion of 55% male and 45% female. Length and weight relationship was negative allometric patterns. Length of first mature (Lm) male and female was 11.95 cm and 10.79 cm respectively. Based on dynamics population analysis it was found that length at first capture (Lc) was 10.44 cm. While K, L∞ and t0 were 0.54/year, 19.6 cm and -0.149 year respectively. In addition there was only one peak recruitment occured in 7th month of recruitment pattern. Another analysis indicated that a value of natural mortality (M) was 1.38 with sea surface temperature (SST) of 29.45°C. According to length frequency data total mortality (Z) was 6.41 so that fishing mortality (F) was calculated to be 5.03. Hence value of exploitation rate (E) was 0.79. It can be concluded that the fisheries resources status is categorized as overfishing.