Abalone Haliotis varia in Tanjung Likupang, North Minahasa, North Sulawesi

Abstract

Abalone (Haliotis varia) is a marine gastropod commonly known as a seven-eyed shell or sea snail. It serves as an important source of marine protein and plays a significant economic role for coastal communities. The abalone has been caught easily by fisherman.  As a result, the abalone population might decrease.  However, there has been limited information of its population in nature up to now. This study aimed to assess the species, density, size, and distribution pattern of abalone in the intertidal zone of Tanjung Likupang, North Sulawesi. Sampling was conducted using the quadrat transect method, with six 25×25 meter (625 m²) placed at two different sites. Each site had 3 replicated.  The results showed variations in abalone density between the two locations. Site 2 had a higher mean density (9.67 individuals/625 m² or 0.02 individuals/m²) compared to Site 1 (7 individuals/625 m² or 0.01 individuals/m²). Size variation at site 1 ranged from 32.9 mm to 52.1 mm (average 40.59 mm), while Site 2 ranged from 20.3 mm to 44 mm (average 38.78 mm). However, statistical analysis indicated no significant difference in both average density and shell length between the two sites. Morisita’s index value was approximately 1 for both locations, suggesting a random distribution pattern. These findings provide a preliminary understanding of the current status of abalone populations in Tanjung Likupang.

Keywords: Abalone, Haliotis varia, density, size distribution

Abstrak

Abalon (Haliotis varia) merupakan gastropoda laut yang dikenal sebagai sumber protein dan bernilai ekonomi tinggi bagi masyarakat pesisir. Abalone mudah ditangkap di alam oleh nelayan.  Hingga populasinya dihipotesa telah menurun di alam.  Namun informasi tentang popualsi abalone adalah masih terbatas sampai saat ini.  Penelitian ini bertujuan untuk mengetahui jenis, kepadatan, ukuran, dan pola distribusi abalon di daerah pasang surut Tanjung Likupang, Sulawesi Utara. Metode yang digunakan adalah transek kuadrat, dengan ukuran 25x25 m (625 m²) ditemaptkan di 2 lokasi.  Maisng-masing lokasi memiliki 3 replikasi. Hasil penelitian menunjukkan adanya variasi kepadatan abalon antara kedua lokasi. Lokasi 2 memiliki kepadatan rata-rata lebih tinggi (9,67 individu/625 m² atau 0,02 individu/m²) dibandingkan dengan lokasi 1 (7 individu/625 m² atau 0,01 individu/m²). Ukuran panjang abalon di lokasi 1 berkisar antara 32,9 mm hingga 52,1 mm, dengan rata-rata 40,59 mm, sedangkan di lokasi 2 berkisar antara 20,3 mm hingga 44 mm, dengan rata-rata 38,78 mm. Meskipun terdapat perbedaan angka, uji statistik menunjukkan tidak ada perbedaan signifikan dalam kepadatan maupun ukuran panjang antara dua lokasi. Nilai indeks Morisita di kedua lokasi mendekati 1, mengindikasikan pola distribusi individu abalon bersifat acak. Temuan ini memberikan gambaran awal tentang kondisi populasi abalon di kawasan Tanjung Likupang.

Kata Kunci: Abalon, Haliotis varia, kepadatan, distribusi ukuran