Electronic Theses and Dissertation

Hiu tikus (Alopias sp.) merupakan jenis ikan hiu oseanik yang hidup pada zona pelagik hingga kedalaman 955 meter. Hiu tikus seringkali tertangkap sebagai tangkapan sampingan atau bycatch pada rawai tuna di perairan lepas utara Aceh dan didaratkan di Pelabuhan Perikanan Samudera (PPS) Kutaradja Lampulo. Terdapat tiga spesies hiu tikus di dunia, namun hanya dua spesies yang ditemukan di perairan lepas pantai utara Aceh, yaitu Alopias pelagicus dan Alopias superciliosus. Studi mengenai ektoparasit yang menginfeksi A. pelagicus dan A. superciliosus yang berasal dari perairan lepas utara Aceh perlu dilakukan dikarena distribusinya yang luas memungkinkan terinfeksi ektoparasit di perairan. Tujuan dari penelitian ini adalah untuk mengidentifikasi serta menghitung tingkat prevalensi dan intensitas ektoparasit yang menginfeksi serta mengetahui rasio jenis kelamin dan variasi morfometrik A. pelagicus dan A. superciliosus dari perairan lepas utara Aceh. Penelitian ini dilakukan pada bulan Juli 2022 sampai April 2023. Pengambilan sampel dilakukan di Pelabuhan Perikanan Samudera (PPS) Kutaradja, Lampulo. Sebanyak 64 individu hiu tikus diamati dan 36 individu ditemukan terinfeksi ektoparasit. Sebanyak 4.092 spesimen ektoparasit ditemukan dari hiu yang terinfeksi. Jenis ektoparasit yang didapat diidentifikasi secara mikroskopis kemudian dihitung tingkat prevalensi serta tingkat intensitasnya. Uji Kai-kuadrat dilakukan guna melihat signifikansi keterpaparan ektoparasit antar spesies hiu. Sebanyak enam jenis ektoparasit berhasil diidentifikasi, yaitu Echthrogaleus denticulatus, Caligus apodus, Nogagus ambiguus, Pagina tunica, Phyllothyreus cornutus dan Paronatrema sp.. Ektoparasit tersebut menginfeksi dengan tingkat prevalensi sebesar 56,25% dan tingkat intensitas infeksi ektoparasit sebesar 113,66 ind/ekor. Uji Kai-kuadrat menunjukkan tingkat prevalensi dan intensitas ektoparasit pada dua spesies hiu tikus berbeda nyata (p>0,05). Hasil penelitian ini dapat menjadi informasi dasar identifikasi populasi hiu tikus A. pelagicus dan A. superciliosus, khususnya di Samudera Hindia, Laut Andaman dan Selat Malaka.
Kata Kunci: Alopiidae, kopepoda, trematoda, Samudera Hindia.

The thresher shark (Alopias spp.) is a type of oceanic shark that lives in the pelagic zone to a depth of 955 meters. Thresher sharks are often caught as by-catch on tuna longlines from off northern Aceh and landed at the Ocean Fishing Port (PPS) Kutaradja, Lampulo. There are three species of thresher sharks in the world, but only two species are found in the waters off the north coast of Aceh, namely Alopias pelagicus and Alopias superciliosus. Study of ectoparasites that infect A. pelagicus and A. superciliosus from the waters off north of Aceh needs to be carried out because of their wide distribution that might be infected with ectoparasites in the waters. The aims of this study were to identify and calculate the prevalence and intensity of infecting ectoparasites and to determine the sex ratio and morphometric variation of A. pelagicus and A. superciliosus from the waters off north of Aceh. This research was conducted from July 2022 to April 2023. Sampling was carried out at the Ocean Fishing Port (PPS) Kutaradja, Lampulo. Total 64 thresher sharks were observed and 36 individuals were found infected by ectoparasites. A total of 4.092 specimens of ectoparasites were recovered from infected sharks. The types of ectoparasites obtained were identified microscopically and then the prevalence and intensity levels were calculated. The Chi-square test was carried out to see the significance of ectoparasites exposure between shark species. A total of six types of ectoparasites were identified, namely Echthrogaleus denticulatus, Caligus apodus, Nogagus ambiguus, Pagina tunica, Phyllothyreus cornutus and Paronatrema sp.. The ectoparasites infected with a prevalence rate of 56.25% and an intensity level of ectoparasite infection of 113.66 ind/fish. The Chi-square test showed that the prevalence and intensity of ectoparasites in the two rat shark species were significantly different (p>0.05). The results of this study can provide basic information for the search for A. pelagicus and A. superciliosus rat shark populations, especially in the Indian Ocean, Andaman Sea and Malacca Strait. Keywords: Alopiidae, copepods, trematode, Indian Ocean.