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|Family:||Heterodontidae Bullhead, horn, or Port Jackson sharks|
|Max. length (Lmax):||cm TL|
|L infinity (Linf):||= cm|
Median Ø' value with related Linf. and K.
Growth & mortality data
|to:||years Estimated from Linf and K.|
|Natural mortality (M):||
Estimated from Linf., K and annual mean temp. = °C
|Life span (approx.):||years Estimated from Linf., K and to.|
|Generation time:||years Estimated from Lopt, Linf., K and to.|
|Age at first maturity (tm):||years Estimated from Lm, Linf., K and to.|
|L maturity (Lm):||
Estimated from Linf. Maturity data
|L max. yield (Lopt):||
|Reproductive guild:||nonguarders: open water/substratum egg scatterers Reproduction|
|Fecundity:||13 [ 10-16 ] Estimated as geometric mean. Fecundity|
|Relative Yield per Recruit (Y'/R):||
Estimate Y'/R from M/K, Lc/Linf and E.
Lc= cm E= /year
Emsy /year Eopt /year
Fmsy /year Fopt /year
Estimate Z, F, E from Lc, Lmean, Linf, K, M
Lc = cm
Lmean = cm
|Resilience / productivity:||
Vulnerable to extinction if decline in biomass or numbers exceeds threshold over the longer of 10 years or 3 generations.
|Intrinsic rate of increase (rm):||/year||
Lr = cm
Estimated from Fmsy at Lc = length of recruitment (Lr).
|Main food:||mainly animals (troph. 2.8 and up)|
|Trophic level:||3.5 +/- s.e. 0.48 Estimated from food data. Food|
|Food consumption (Q/B):||times the body weight per year||
Enter Winf, temperature, aspect ratio (A), and food type to estimate Q/B
Winf = g Temp. = °C
|Note: The estimates are derived from default values taken from FishBase and will thus not be appropriate for every population. You can change these values and recalculate the life history parameters.||
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