August 15, 1964 (cont.)
Rats:
Wm. Jackson--a very dense rat population.
An ideal
situation for extensive studies of a population at such a high
density.
All rats caught were Polynesian rats
Traps were set out in early afternoon.
(Rattus exulans).
Most were inspected in
the afternoon and again in early evening;
about half the total
catch was obtained before dark.
Total catch 65.
vaginal orifices,
uterine scars,
Of the females (N-27) all had perforated ,
indicating sexual maturity.
Only 2 lacked
indicating pregnancy at a previous time, and only
l was pregnant.
Of the males
(N-35)
only 5 were not mature.
were smaller than the mature individuals.
These five
Males were,
in general,
larger than the females.
Possible explanations of population state:
this is the non-
breeding season, or population pressure has reduced reproduction. .
--Atrophied condition of female reproductive tract
--Lack of young individuals
Could support either hypothesis~-the high prevalence of uterine
scars supports the breeding season hypothesis.
Three skins were prepared.
preserved.
No fleas or lice seen
Stomachs,
adrenals,
and lungs were
(not thoroughly checked for)
but mites were found and preserved.
oe
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