Caretta caretta MED (Loggerhead turtle, Mediterranean):  

Predictions & Data for this entry

Model:  std  

COMPLETE = 2.8
MRE = 0.210
SMSE = 0.273

Zero-variate data
DataObservedPredicted(RE)UnitDescriptionReference
ah49.08 48.66 (0.008524)dage at hatchReidMarg2009
ab55.18 56.76 (0.02863)dage at birth GodfMros1997, Stok2014
ap7300 4331 (0.4068)dage at puberty CasaCont2011, PiovClus2011
am2.446e+04 2.046e+04 (0.1633)dlife spanWiki
Lb4.1 5.481 (0.3369)cmSCL at birth MargArga2003, ReidMarg2009
Lh4.1 5.48 (0.3365)cmSCL at hatching MargArga2003, ReidMarg2009, BennTapl1986
Lp_SCL64.2 65.33 (0.0176)cmSCL at puberty MargArga2003, Groom1990, TiwaBjor2000
Lp_CCL 69 70.5 (0.02172)cmCCL at puberty MargArga2003, Groom1990, TiwaBjor2000
Li_SCL 87 79.22 (0.08946)cmultimate SCL MargArga2003, Groom1990
Li_CCL 91 85.48 (0.06061)cmultimate CCL MargArga2003, Groom1990
Wwb16.1 22.68 (0.4087)gwet weight at birth MargArga2003, ReidMarg2009
Wwp5.2e+04 3.84e+04 (0.2616)gwet weight at pubertyGroom1990
Wwi8.7e+04 6.846e+04 (0.2131)gultimate wet weightGroom1990
E01.7e+05 2.024e+05 (0.1903)Jinitial energy content of the eggHaysSpea1991
Ri0.6575 0.591 (0.1012)#/dmaximum reprod rate MargArga2003, Groom1990, BrodGlen2003, TiwaBjor2000
Uni-variate data
DatasetFigure(RE)Independent variableDependent variableReference
Tah see Fig. 1 (0.04377)temperatureage at hatchingReidMarg2009
tW_T3 see Fig. 2 (0.3148)time since birthtotal wet weightCate2014
tW_T4 see Fig. 2 (0.0819)time since birthtotal wet weightCate2014
tW_2202 see Fig. 3 (0.2843)time since birthtotal wet weightCate2014
tW_2207 see Fig. 4 (0.125)time since birthtotal wet weightCate2014
tW_2211 see Fig. 4 (0.1607)time since birthtotal wet weightCate2014
tW_2213 see Fig. 3 (0.2034)time since birthtotal wet weightCate2014
tW_2215 see Fig. 4 (0.1973)time since birthtotal wet weightCate2014
tW_2217 see Fig. 3 (0.06633)time since birthtotal wet weightCate2014
tW_2218 see Fig. 3 (0.07374)time since birthtotal wet weightCate2014
tW_2222 see Fig. 4 (0.09574)time since birthtotal wet weightCate2014
tL_2207 see Fig. 5 (0.1387)time since birthCCL total lengthCate2014
LW_2207 see Fig. 6 (0.1675)curved carapace lengthwet weightCate2014
tL_2210 see Fig. 5 (0.07511)time since birthCCL total lengthCate2014
tL_2211 see Fig. 5 (0.0747)time since birthCCL total lengthCate2014
LW_2211 see Fig. 6 (0.1997)curved carapace lengthwet weightCate2014
tL_2222 see Fig. 5 (0.04918)time since birthCCL total lengthCate2014
LW_2222 see Fig. 6 (0.08741)curved carapace lengthwet weightCate2014
tW_2226 see Fig. 7 (2.169)time since birthtotal wet weightCate2014
tL_2226 see Fig. 8 (0.4455)time since birthstraight carapace lengthCate2014
LW_2226 see Fig. 9 (0.0917)straight carapace lengthwet weightCate2014
tW_2302 see Fig. 7 (0.1608)time since birthtotal wet weightCate2014
tL_2302 see Fig. 8 (0.08075)time since birthstraight carapace lengthCate2014
LW_2302 see Fig. 9 (0.1593)straight carapace lengthwet weightCate2014
LF see Fig. 10 (0.2066)SCLeggs per clutch TiwaBjor2000
tL_CasaPino2009 see Fig. 11 (1.473)ageCCL CasaPino2009
tL_CasaConte2011 see Fig. 11 (1.794)ageCCL CasaCont2011
Pseudo-data at Tref
DataGeneralised animalCaretta caretta MEDUnitDescription
v 0.02 0.06981cm/denergy conductance
kap 0.8 0.6481-allocation fraction to soma
kap_R 0.95 0.95-reproduction efficiency
p_M 18 15.96J/d.cm^3vol-spec som maint
k_J 0.002 0.00098721/dmaturity maint rate coefficient
kap_G 0.8 0.7465-growth efficiency
k 0.3 0.4853-maintenance ratio

Facts

  • Long lived species. Life stages: hatchling, pelagic juvenile, benthic juvenile, adult; switch from pelagic to benthic stage(recruitment) happens at a certain size, probably smaller than in NA, between 30-35cm CCL (ref: Bjor2000, CasaCont2011)
  • Compared to the North Atlantic population, they are smaller, possibly reach maturity younger, have more eggs per clutch but less clutches per year (ref: MargArga2003, Groom1990, BrodGlen2003)
  • Mean temperature experienced: SST of Mediterranean 19C in the west, 20C in the east basin (ref: Nykj2009)
  • Hatching can last up to 24hrs. (ref: BennTapl1986)
  • Hatching (exit the egg) to emergence (exit the nest) interval estimated as 4.1days at 30C (ref: GodfMros1997)
  • Yolk bag absorbed 24-48 hours after emerging, tissue density of 0.28 reported (ref: KraeBenn1981)
  • Onset of feeding observed in sea water (at 27 C) 2-3 days after emergence = approximated as birth (ref: Stok2014)
  • After emerging observable weight loss for the next 2-3 days (6-7 days total after hatching), connected to loss of water - not modelled (ref: BennTapl1986)

Discussion

  • for the Mediterranean population
  • SCL = Straight Caparace Length (preferred)--> del_MS, CCL - Curved Carapace length --> del_MC
  • Parameter values were based on Caretta_caretta_NA (as in January 2016), and these are the values in the pars_init file. It was assumed that certain parameters are species (not population) specific and therefore they were not released for estimation. These parameters are: z, del_MS, kap, E_G, T_A. In addition, a set ofparameters that were not estimated (due to insufficient data) for the NA population were not estimated for the MED population either: {F_m}, kap_X, kap_P, p_T. k_J, s_G. The scaled functional response (f) was guestimated from data as L_i/L_m = 0.6692, while assuming that L_m is also species (not population) specific and therefore using the largest NA female (130 cm SCL) as L_m.
  • Distinction between hatching (exit the egg shell) - emergence (exit the nest)- birth (onset of feeding).[see Facts4-8 for more details].
  • "Hatching" is added as an event with a maturity threshold E_Hh.Hatching-to-emergence period depends primarily on abiotic factors such as sand temperatureand grain size, so a "maturity level at emergence" was not introduced.
  • Ontogenetic habitat shift is occuring mostly during the juvenile stage and it generally means food of better quality, and higher temperature -> For data from wild, polyphasic growth curve was constructed, with CCL 30 cm as L_switch. This data set was not used in parameter estimation (data weight set to zero).
  • Age at puberty reported in literature is mostly deduced from size at first nesting + bone growth marks;onset of investement into reproduction may be sooner
  • Reproduction was modeled as continous, and then approximated as eggs per clutch. Predictions for the # of eggs as a function of length are quite far off data. This might be a result of the constraint (put in the form of auxData.fecund)that all turtles have the same number of clutches and eggs per clutch. This is not true, but is a first approximation for translatingfrom number of eggs (predicted) into number of eggs per clutch (reported in literature). Possibly allocation into clutches should be alsoa function of size, or a function of seasonal reproduction output : i.e., that smaller turtles make fewer clutches than larger turtles.That way, smaller turtles would have more eggs per clutch, resulting in a more horizontal curve.
  • Figs 6 and 7 (growth data) have 2 data sets but it seems that they are predictedwith the same curve. There are in fact two curves in those figures - one is overlapping with theother. This is a good example of interindividual variability: I parse the same temp and food (becausethe animals were kept under same conditions in individual tanks), and the growth curves are predictedusing the same parameter set. The observed differences are either a result of inter-individualvariability between individuals of the same (MED) population, or the two turtles had differentfathers with the faster growing one possibly being of the MED origin (see PiovClus2011).
  • Some notes on parameters: d_V is set to 0.28 in pars_init after KraeBenn1981.f for zero-variate is set to 0.6923 as Li/Lm=90/130 where Li is the max length of the med population and Lm is the max length ever observed.

Bibliography

  • Wiki
  • Kooy2010
  • BennTapl1986
  • Bjor2000
  • BrodGlen2003
  • Cate2014
  • CasaCont2011
  • CasaPino2009
  • GodfMros1997
  • Groom1990
  • HaysSpea1991
  • KraeBenn1981
  • MargArga2003
  • Nykj2009
  • PiovClus2011
  • ReidMarg2009
  • Stok2014
  • TiwaBjor2000

Bibtex files with references for this entry


Nina Marn, 2017/04/18 (last modified by Bas Kooijman 2017/11/20)

accepted: 2017/11/20

refer to this entry as: AmP Caretta caretta MED version 2017/11/20 bio.vu.nl/thb/deb/deblab/add_my_pet/