Hubungan panjang cagak dan laju tangkap dengan distribusi area tuna sirip biru selatan (thunnus maccoyii castelnau, 1872) hasil tangkapan long line di perairan Samudera Hindia = Relationship between fork length and hook rate with the area distribution of southern bluefin tuna (thunnus maccoyii castelnau, 1872) caught by long line in the Indian Ocean