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158
RESIJLTS /DI SCUSS IOII
Age of
laying
During 1981, at an age of 7 years, the.first 2 oaptive r:eared
anin.is (colrected in i975176) ;tarted laYing eggs of a mean weight
of 46.7q. Bv 1984 J fetnales were faying and continued to do so,
untir iri 1981. An additionaf 2 fenales started laying, at an age of
f2l13 years. I'inally by 1989 aI1 6 fenales had connenced laying,
the 1a;t to start tayinq at an a.Je of .13 years' AII felnal es
continued to lay every season crnce they had conulenced their
breeding cyc1e.
The data for 1986 is discarded in this paper as lhe supervi sion and
accuracy of the reco!:ding is undera questicn'
Tlte results indicate that captive breal fenales can star.t egg laying
as early as 7 years o]d at a lenqth of arounC 2 n' but the in'r]or'lty
only st-art laiing bet',teen the ages of 12 to l3-years, r'Jith size
2.3-5n. It hai been nentioned earlier that fema-ie Iaying ts
dependent on length and not necessari-Ly on ;rqe. According !o lhe
re;ults (Table :lt, age seens to be tbe $ore pronineDt factor'
The age of a crocodi,le is very easily conlused, if the exact
hatchi;g date 16 not know. The above fenales showed qro!'ths of 6'6
crn yr-'after rEachinq 2 n in around 1941. This lrould nean that a
length difference of 66 cn between anihals would correlate to a 10
y"ui diff"..n". in qrowth. These recults tend to indicate lhat it
is the aqe of the fenale rather than her length rnhich is the
determining factor on the quantity of eggs produced.
xurber of eggs laid
The nean egg nunbets of all the fena-tes put together have
pr:oqressivety increased over the last l'0 years. In 1983 a total of
i: .qq= uere taio, white in 1992 iL had j.ncreased to 199 eggs
irulf-. z). The first laying -ln I98l saw only tto fernates laying,
nith nests of 5 and 8 eggs (av.6.5\t bY L992 r"ith six nests the
cluteh sizes varied frcm 27 la 43 eggs, r"ith a nean of 33 eggs per
fernale (Table 3).
The largest female (fl/76) and t'he last one to start laying at an
aqe of t3 years, renarkably produceci the largest clutch nunlrers
fion the fi;st }aying season (13 eggs in 1989) to the present dat-e
(43 eqgs Lgg2). it produced nore eggs iD the fj'rst layinq season
inan tne females who had already been -Iayinq for 6 years' Does
this trend mean that the older the fenale is before starting to
tav, the greater will be the initial clutch sizes ? Is egg nunber
deiendent- on fenale size ? What nechanisn trigge!'s the fenales
fiist Iaying season ? can they controL this ? or is it iust
geneticallY determined.
The individual fenales have all sholrn increases in egg production
lrith their increase in age. I{owever ' so!!e individuals have had
a""pr i" their egg production over 2 year perio