Crocodylus niloticus: Population traits

at T = 22 °C with background hazards for embryo, juv, adult: 0, 0, 0 1/d

Ln survival probability as function of age, with (dashed) and without (solid) thinning at max (red) and min (blue) scaled functional response for females.
Ln survivor function of the stable age distribution as function of age, with (dashed) and without (solid) thinning at max (red) and min (blue) scaled functional response for females.
model std f_min f_max date: 2025/07/16
symbol units thinning falsethinning true thinning falsethinning true description
femalemale femalemale femalemale femalemale
f - 0.566095 0.566095 0.573831 0.573831 1 1 1 1 scaled functional response
r 1/d 0 0 0 0 0.00093368 0.00093368 0.000229551 0.000229551 spec pop growth rate
t2 d NaN NaN NaN NaN 742.382 742.382 3019.58 3019.58 population doubling time
a_b d 238.028 235.504 237.669 NaN 225.588 223.917 225.588 223.917 age at birth
t_p d 33690.2 9893.92 17407.6 NaN 4577 4215.34 4577 4215.34 time since birth at puberty
S_b - 1 1 1 NaN 1 1 1 1 survival probability at birth
S_p - 0.999998 0.999998 0.388685 NaN 0.999998 0.999998 0.333984 0.326654 survival probability at puberty
theta_0b - 0.00565913 0.00539427 0.256937 NaN 0.189885 0.188619 0.457805 0.464629 frac of ind that is embryo
theta_bp - 0.0056612 0.00539624 0.159536 NaN 0.153866 0.15308 0.251624 0.252719 fraction of individuals that is juvenile
theta_pi - 0.98868 0.989209 0.583527 NaN 0.656249 0.658301 0.290571 0.282651 frac of ind that is adult
L_bi cm 26.8829 29.5725 15.9633 NaN 10.017 10.3415 7.21873 7.25912 mean structural length of post-natals
L2_bi cm^2 751.858 911.246 383.362 NaN 141.954 153.072 99.484 103.028 mean squared structural length of post-natals
L3_bi cm^3 21378.3 28559.5 10438.3 NaN 2590.61 2939.74 2320.92 2539.43 mean cubed structural length of post-natals
Ww_bi g 70511.2 100981 34756.2 NaN 13108.1 16108.4 11743.5 13914.9 mean wet weight of post-natals
L_pi cm 27.0181 29.7159 19.4652 NaN 11.57 11.952 10.6537 10.8281 mean structural length of adults
L2_pi cm^2 756.101 916.157 485.401 NaN 172.472 185.885 176.244 185.348 mean squared structural length of adults
L3_pi cm^3 21500.5 28715.1 13283.1 NaN 3188.18 3613.37 4298.67 4776.24 mean cubed structural length of adults
Ww_pi g 70914.3 101532 44228.3 NaN 16131.7 19799.5 21750.6 26171.5 mean wet weight of adults
R 1/d 0 0.0394974 0 NaN 0 0 0 0 mean reproduction rate of adults
J_X g/d 82.5662 110.414 42.6747 NaN 27.5374 32.7637 19.2988 22.0522 mean ingestion rate of wet food by post-natals
Y_PX mol/mol 0.109375 0.109375 0.109375 NaN 0.109375 0.109375 0.109375 0.109375 yield of faeces on food
Y_VX mol/mol 0 0 0 NaN 0.0878367 0.083775 0.0276063 0.0264341 yield of living structure on food
Y_VX_d mol/mol 0.0074391 0.007194 0.0181728 NaN 1.51738e-05 1.31164e-05 0.0496281 0.0477902 yield of dead structure on food
Y_EX mol/mol 0 0 0 NaN 0.356604 0.375271 0.112077 0.118412 yield of living reserve on food
Y_EX_d mol/mol 0.017097 0.0182427 0.0423366 NaN 6.16033e-05 5.8755e-05 0.201482 0.214077 yield of dead reserve on food
Y_CX mol/mol 0.703697 0.702965 0.674469 NaN 0.362463 0.3506 0.406113 0.393179 yield of CO2 on food
Y_HX mol/mol 0.748205 0.747427 0.717128 NaN 0.385388 0.372774 0.431798 0.418047 yield of H2O on food
Y_OX mol/mol -0.893154 -0.892225 -0.856057 NaN -0.460049 -0.444992 -0.515451 -0.499035 yield of O2 on food
Y_NX mol/mol 0.162392 0.162223 0.155647 NaN 0.0836452 0.0809076 0.0937183 0.0907336 yield of N-waste on food
mu_TX J/mol 451452 450953 432533 NaN 228326 220226 256851 248092 yield of heat on food

Remarks

  • Reprod-code O applies. Sex ratio is assumed to be 1:1. Parameters of male and female differ.
  • Buffer handling rule: release each egg as soon as reproduction buffer allows
  • Weights of adults do not include reproduction buffer