Electronic Theses and Dissertation

Lobster air tawar (Cherax quadricarinatus) merupakan salah satu spesies yang hidup menempati sela-sela bebatuan pada dasar perairan berlumpur. Danau Laut Tawar di Aceh Tengah dengan luas 5.740,10 Ha memiliki sumber daya perikanan lobster air tawar yang sengaja dimasukkan sebagai organisme invasif yang dapat memanfaatkan bahan organik pada dasar danau. Studi kebiasaan makan terhadap organisme akuatik di alam berperan penting dalam usaha budidaya organisme tersebut, terutama aspek pakan. Penelitian ini bertujuan untuk menganalisis kebiasaan makan C. quadricarinatus di Danau Laut Tawar, Kabupaten Aceh Tengah. Pengambilan sampel acak sederhana telah dilakukan untuk mendapatkan sampel C. quadricarinatus di tiga stasiun pendaratan lobster air tawar. Sebanyak 35 sampel C. quadricarinatus telah didapatkan dan bagian lambung serta ususnya diawetkan menggunakan larutan formalin dengan kepekatan 4%. Jenis makanan C. quadricarinatus diamati dengan metode lapang pandang di bawah mikroskop di Laboratorium Kesehatan Ikan dan Lingkungan, BBI Lukup Badak, Dinas Perikanan Kabupaten Aceh Tengah. Parameter yang dihitung, antara lain persentase volume, frekuensi kejadian, indeks bagian terbesar makanan (Index of Preponderance), panjang usus relatif, dan penentuan luas relung makanan. Hasil penelitian menunjukkan komposisi makanan C. quadricarinatus terdiri dari detritus, cacing (Polychaeta), zooplankton (Oithona), potongan daun, dan 20 genus fitoplankton yang terdiri dari sembilan kelas (Chlorophyceae, Zygnematophyceae, Cyanophyceae, Charophyceae, Ulvophyceae, Bacillariophyceae, Macroconidia, Pteridopsida, dan Deutromycetes). Nilai Index of Preponderance (IP) menunjukkan makanan utama C. quadricarinatus di semua stasiun adalah detritus, yang memiliki nilai IP sebesar 95,62%. Jenis makanan lainnya tergolong pada kategori makanan tambahan karena memiliki nilai IP kurang dari 4%. Jenis makanan C. quadricarinatus berdasarkan selang ukuran kelas menunjukkan semakin besar ukuran lobster, maka jenis makanan yang dikonsumsi semakin sedikit.

Kata kunci: detritus, lambung, invasif, relung.

Freshwater lobster (Cherax quadricarinatus) is a species that lives on the sidelines of rocks at the bottom of muddy waters. Laut Tawar Lake in Central Aceh with an area of 5,740.10 Ha has a freshwater lobster fishery resource which is deliberately included as an invasive organism that can utilize organic matter at the bottom of the lake. The study of feeding habits on aquatic organisms in their natural habitat plays a crucial role in the cultivation of these organisms, especially in terms of their diet. This research aims to analyze the feeding habits of C. quadricarinatus in Lake Laut Tawar, Central Aceh Regency. Simple random sampling was conducted to obtain samples of C. quadricarinatus from three freshwater lobster landing stations. A total of 35 samples of C. quadricarinatus were obtained, and their stomach and intestines were preserved using a 4% formalin solution. The food types of C. quadricarinatus were observed using a field observation method under a microscope at the Fish Health and Environment Laboratory, BBI Lukup Badak, Central Aceh Regency Fisheries Department. Parameters calculated included volumetrix index, occurrence frequency, Index of Preponderance, relative length of the gut, and determination of food niche breadth. The research results showed that the food composition of C. quadricarinatus consisted of detritus, worms (Polychaeta), zooplankton (Oithona), leaf fragments, and 20 phytoplankton genera consisting of nine classes (Chlorophyceae, Zygnematophyceae, Cyanophyceae, Charophyceae, Ulvophyceae, Bacillariophyceae, Macroconidia, Pteridopsida, and Deutromycetes). The Index of Preponderance (IP) values indicated that the main food for C. quadricarinatus at all stations was detritus, with an IP value of 95.62%. Other food types were categorized as supplementary food since they had an IP value of less than 4%. The types of food consumed by C. quadricarinatus based on size class intervals showed that as the size of the lobster increased, the variety of consumed food types decreased. Keywords: detritus, stomach, invasive, niche.