The daily cycle of _T. ornata_ consists basically of periods of
basking, foraging, and rest that vary in length depending upon
environmental conditions. Turtles emerge from burrows, forms, and
other places of concealment soon after dawn and ordinarily bask for at
least a few minutes before beginning to forage; foraging is combined
sometimes with basking, especially in open areas that are suitable for
both kinds of activity. Foraging usually continues until shelter is
sought sometime between mid-morning and noon. Turtles remain under
cover (or continue to forage in shaded areas) until mid-afternoon or
late afternoon when they again become active. They forage in both
morning and afternoon. Study of travel records of a few of the turtles
equipped with trailers suggests that, under normal conditions,
activity is slightly greater in forenoon than in afternoon, but that
the converse is true of gravid females seeking nesting sites. Strecker
(1908:79) reported that captive _T. ornata_, after developing a
feeding reflex, ate and retired until feeding time next day.
As environmental temperatures rise in summer, the period of mid-day
quiescence is lengthened. In the hottest part of the year, some
turtles remain under cover for several days at a time. In periods of
clear, cool weather at the beginning and end of the growing season,
some turtles remain abroad and bask for most of the day.
Examination of thread trails showed that activity of all individuals
except nesting females was terminated at dusk. Breder (1927:236),
Allard (1935:336), and Stickel (1950:358) reported a corresponding
lack of nocturnal activity in _T. carolina_. _Terrapene o. ornata_ in
Kansas, and _T. o. luteola_ in New Mexico (Norris and Zweifel,
1950:2)--unlike desert tortoises, _Gopherus agassizi_, which are
active at night in hot weather (Woodbury and Hardy, 1948:186)--do not
utilize the hours of darkness for foraging, even in the hottest part
of the year.