Table 3. Spawning potential ratio (SPR) and some biological reference ponts for giant catfish (Netuma thalassina) in Gunungkidul waters

M Methods	Input					Outputs
	L∞ (cm)	K (year–1)	M (year–1)	Lm50 (cm)	Lm95 (cm)	SPRcur	Fcur (year–1)	F20% (year–1)	F40% (year–1)
AC	61.3	0.22	0.34	37	41	0.26	0.43	0.55	0.26
Al	61.3	0.22	0.35	37	41	0.27	0.42	0.57	0.28
Jn	61.3	0.22	0.33	37	41	0.25	0.44	0.54	0.26
ZM	61.3	0.22	0.23	37	41	0.16	0.54	0.44	0.22
Th	61.3	0.22	0.47	37	41	0.43	0.30	0.69	0.34
Mean ± SD	61.3	0.22	0.35 ± 0.09	37	41	0.28 ± 0.11	0.42 ± 0.09	0.56 ± 0.10	0.28 ± 0.05

AC, Al, Jn, ZM and Th as the natural mortality (M) by Alverson & Carney (1975), Alagaraja (1984), Jensen (1997), Then et al. (2015), Zhang & Megrey (2006).
F_cur, current fishing mortality; F_20% and F_40%, fishing mortality that remained 20% and 40% SPR.