Data about maximum thermal tolerance in marine organisms are needed to prevent the extinction of species due to global warming. The aim of this study is determining the maximum lethal temperature of Haliotis squamata. In this study, H. squamata were placed in individual containers and exposed to 5 different levels of temperature (27°C, 28.5°C, 30°C, 31.5°C, and 33°C, n = 20). The temperature was raised 0.5°C per 12 hours starting from ambient conditions until target temperatures were reached. The mortality was monitored since animals moved to the individual containers. The results showed that the maximum thermal limit of H. squamata is 31.5°C and 33°C is the lethal temperature, the temperature level with the lowest survival rate (0.15). The IPCC predict that sea surface temperature will raise up to 4°C and monthly average sea surface temperature in Indonesia is around 26 – 31°C. That means in the next century average sea surface temperature could be more than the maximum thermal limit of H. squamata. Thus, early conservation is needed to protect H. squamata.

Perairan umum daratan Indonesia memiliki keanekaragaman jenis ikan yang tinggi, sehingga tercatat sebagai salah satu perairan dengan mega biodiversity di Indonesia. Salah satu upaya dalam pengelolaan sumberdaya perikanan secara lestari sebagaimana diamanatkan dalam UU No 31 Tahun 2009 tentang Perikanan, maka diperlukan data dan informasi tentang jenis dan morfologi ikan di suatu perairan. Tujuan dari penelitian ini adalah untuk mengetahui dan mengidentifikasi jenis dan morfologi ikan hasil tangkapan nelayan Pantai Tapak Paderi Kota Bengkulu. Manfaat dari penelitian ini adalah memberikan informasi mengenai jenis-jenis dan morfologi ikan hasil tangkap nelayan Tapak Paderi Kota Bengkulu. Teknik yang digunakan dalam pengambilan sampel yaitu metode pengumpulan sampel yang digunakan adalah Random sampling, sampel ikan laut diambil secara acak langsung dari Nelayan Tapak Paderi. Identifikasi yang dilakukan adalah menghitung panjang total, panjang baku, identifikasi diawali dengan memperhatikan dan mencatat bagian morfologi ikan laut antara lain: warna, posisi mulut, bentuk tubuh, tipe sisik, bentuk sirip ekor, jenis dan jumlah duri pada masing-masing sirip. Berdasarkan hasil penelitian yang diperoleh berhasil menginventarisasi 12 jenis ikan laut hasil tangkapan nelayan di Pantai Tapak Paderi Kota Bengkulu

Ocean warming is affecting marine ectothermic herbivores as well as the macroalgal species they consume and this has the potential to alter their trophic interaction. However, it is currently still unknown how these two important components of benthic food webs will react to a warming environment. Consumption rates of grazers change with increasing temperatures, but it is unclear whether this is also true for feeding preferences. In this study, multiple-choice feeding assays with the tropical abalone Haliotis squamata from Western Indonesia were conducted in August 2018. After brief acclimation of either the grazer or the macroalgae to moderately elevated water temperatures (maximum 2 °C above the long-term average) in the laboratory, three species of living macroalgae were simultaneously offered to the abalone in feeding assays. Consumption rates of H. squamata were lower under elevated water temperatures, while its feeding preference switched: At 27 °C (2 °C below long-term average), abalone preferred non-acclimated Gracilaria salicornia, but switched to non-acclimated Amphiroa spp. at 31 °C. Interestingly, no such switch in preference occurred when the macroalgae, but not the grazers were acclimated. This indicates that the grazer will presumably be the driver of this potential change in interactions between H. squamata and its macroalgal food. Ocean warming may result in changes in the structure of benthic communities, mediated by changes in the feeding behaviour of herbivorous invertebrates.

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