David S. Lee and Mike Lowe, © 2007 The Tortoise Reserve
Introduction:
This note is based on a captive group of Golden Greek Tortoises we
purchased from reptile dealers between April and August 2002 and an
individual donated from a tortoise rescue group in Maryland. The
animals were acquired through three different sources. The composite
group consisted of 6.6 adult tortoises. The males range from 360-430
grams and 126-130 mm standard carapace length. The females range from
800-1045 grams and 155-165 mm standard carapace length. Taxonomic
arrangement of the Greek Tortoise complex is confusing and unsettled. At
this time Golden Greek Tortoises (a popular hobbyist trade name) are
recognized as Middle Eastern spur-thighed tortoises, Testudo (graeca) terrestris
Forskal, 1775. The founder stock of our group is believed to come from Syria, but they
also occur in Turkey and northern Iraq.
According to Bonin, et al. (2006 Turtles of the World) no studies have
been published on this tortoise.
Medical treatment:
Immediately upon acquisition all tortoises were dewormed with panacure.
Dosage was 50mg/kg for three consecutive days. This same dosage was
repeated two weeks later. Each was also treated with enrofloxacin for
respiratory ailments, a problem with all imports we examined. Dosage was
5mg/kg daily over a course of 3 weeks. Three of our tortoises continued
to exhibit occasional reoccurring runny noses. This condition seemed to
coincide with dampness, high humidity and foods with high moisture
content. Individuals were retreated with enrofloxacin as needed. A group
maintained outside throughout the year also occasionally showed signs of
reoccurring respiratory problems but they were not retreated. Their
respiratory problems seemed to be resolved through their own
thermogulatory behavior. Two tortoises in the outdoor group died, but
based on the timing of death neither mortality seemed to be associated
with hibernation. A female died of unknown problems, and one male died
which on examination showed extensive liver liaisons. This male was
active and feeding the week prior to its death. Both these individuals lived
approximately one year under our care. At the time of this writing
the remaining tortoises in our founder group all appear to be healthy.
Neither group has been in contact with any other species of chelonian
since acquisition.
Housing:
Our tortoises are divided into two groups, each is managed differently.
One group is left outside throughout the year, the other is moved from
out door to in door enclosures based on season and weather. Thus far we
have confirmed reproduction in both group, but we have not had successful
hatchling of eggs left in the ground, and while we have certainly missed
finding some clutches no hatchlings have appeared in the pens. Apparently
local weather conditions or soil types fail to provide adequate or consistent
incubation conditions. Hatchlings and young are kept inside during winter
months.
One group is kept outside primarily during the summer. They are brought
in during extended rainy periods, and at night in the spring and fall
when the night temperatures are expected to drop below 65 F or when
there is heavy dew. The winter, in door enclosure is 3 x 5 feet, the
outside enclosure is 4 by 6 feet (six adult tortoises). The outside
enclosure is a box frame made from pressure treated 2 x 10 boards and
covered with a wire top. A 12-inch board is mounted across one end for
shade. The frame has no bottom and is daily moved about a mowed lawn,
providing constant availability of new vegetation growth for the tortoises.
The inside enclosure is illuminated by a 60 watt bulb for 11-12 hours a day,
and heated by a 100 watt ceramic heater which stays on constantly. Even
during the winter the tortoises are put out doors 1-2 times a week on
warm sunny days.
The second group lives outside throughout the year. The weather in SE
North Carolina is mild in the winter and hot and humid in the summer. It
regularly gets below freezing from December through February. Frost
typically begins in November. We should note that 2002 was the driest
year on record for this part of the state and 2003 was the wettest. A
rain gauge is mounted on the pen’s fence and total rain is recorded
weekly. (On a week in mid April and again in early August we had 4.5
inches of rain, and many weeks we had 2 or more inches) No signs
of poor health were associated with any extreme weather conditions. The
tortoises are housed in a pen with southern exposure, the total area is
just over 300 square feet, with two separate sheltered areas under boxed
in steps and under a small elevated building. The building is closed in
at ground level and the areas accessible to the tortoises under the
building and steps are each approximately 2.5 x 3 feet. The protected
area under the steps is open on the south side for the tortoises to have
access, the one under the house has only a small 8 x 8 inch opening for
access. Both of the protected areas have about 3 inches of cypress mulch
over a dirt floor. The pens’ fencing is about 2.5 feet high and is
buried into the ground about 10 inches. It is made of pressure treated
wood. The fence is built as a solid visual barrier so the tortoises do
no constantly walk the pen’s perimeter. Above the fencing at 1 inch, 1
foot, and 2 foot intervals are strands of 20 gauge wire for an electric
fence. A ground wire was installed several inches above the soil on the
outside of the pen. Despite the presence of bobcats, raccoons, gray
foxes, coyotes, feral dogs, and black bears on the property we have had no
problems with predation. Several dirt mounds, tree trunks and shrubs are
present in the pen and portions of the pen are shaded at various times
throughout the day by several pine trees growing in and adjacent to the
pen. The tortoises use the mounds and the fencing to angle themselves
for maximum exposure to solar radiation early in the morning. The soil
is a loose sandy loam, which drains quickly. Even during periods of
heavy rain no standing water has been observed. Several inches down the
soil is sometimes quite moist during, but the drainage is probably a
key factor in keeping the tortoises healthy during wet periods. Despite
frequent seeding, by the end of the summer the ground is 85% bare except
for some low growing evergreen Smilax bona-nox, the tortoises don’t eat
this but it provides good cover. Other native and naturalized plants
growing in the pen, which are not eaten, are probably two tall for the
tortoises to reach. Like other Testudo they are grazers and not
browsers. These tortoises are seldom handled, and when active will run
for cover when they see people approach. They spend long periods sitting
in the same relative positions, and each tortoise has three or four
preferred stations where they spend a good portion of each day. In an
adjacent and similarly constructed pen which faces SE and abuts the same
building a captive group of adult Testudo (graeca) lbera are maintained.
Their behavior, periods of activity, and thermal regulation are similar
through they are less active on cooler days than the Golden Greeks.
These tortoises are also kept outside throughout the year. No artificial
heating devices are used on either group.
Diet:
Considering their small size these tortoises eat large amounts of food
daily. None were observed to drink from open water containers nor did
they show any interest in soaking. We have been unable to get either
group of these tortoises to feed on commercial tortoise chows, though
the same brands are eaten by other taxa of T. gracea in our collection.
Fruits are seldom offered, and not eaten with any frequency when they
are. We have not seen them eating mushrooms. When maintained outside
these tortoises feed mostly on plants growing in their enclosures with
supplemental feedings of grocery store produce at least once a week (see
list below). The tortoises typically walk about eating small amounts of
native and naturalized vegetation and then move a foot or two before
they continue foraging. New broad-leafed vegetation planted in the pen
is soon discovered and usually completely consumed that day. The
differences in vegetation, both in density and in diversity is striking
when comparing what is growing naturally outside vs inside the fence.
The other group is housed outside in a movable pen so that fresh plant
growth is always available. ‘Naturally growing’ food items include
clover, dandelions, plantain, and various grasses. This is supplemented
with squash, hibiscus flowers, carrots, corn, okra, and dark green
lettuce (for its moisture content). In the late fall when the tortoises
are less active the pen in which tortoises are housed throughout the
year is seeded with grasses, clover, and seed mixes used for wildlife
food plots. Note that the less expensive lawn seed has a higher content
of seeds of lawn type ‘weeds’ and this is there for preferred for tortoise
pens when compared to high grade more expensive seed. The pen’s interior
is lightly fertilized in early spring. Actually the care of the ground
so that it supports the best possible forage crop possible is more work
than the actual husbandry of the tortoises. In the winter the group that
is not hibernated is fed primarily on endive, various dark lettuces,
collards, and squash supplemented with calcium powder.
When the tortoises are outside food is randomly scattered throughout the
pen. When the tortoises are fed indoors in smaller containers the food is
placed in a liner fashion so that all animals have access to the food
simultaneously. This is in contrast to dish feeding where three or four
tortoises have primary access to the food. Uneaten food is removed a few
hours after feeding.
When inside the tortoises are fed almost daily but this is not necessary, it is
more an artifact of activity in the care of other species housed in our collection.
Tortoises housed outside throughout the year are not fed from late October
through mid to late March, though by March they are frequently seen grazing on
various plants that are naturalized in their pens.
Behavior:
Basking: Tortoises bask during mid morning hours, with exact times
varying with the season and weather. During the heat of the day they
seek shade or cover, during cool periods they move from spot to spot as
patches of direct sun shift through out the day. On intermittent cool
cloudy days they stay primarily inside their retreats. During cool
weather in the fall the tortoises will dig into the substrate seeking
sites and positioning themselves so that the morning sun warms the
exposed posterior portion of their shells. By the time the air
temperature is in the high 60s F, the ground temperature in areas where
the pen is receiving full sun is often 85 F and by the time air
temperature is in the low 70s the tortoises are in places where the
temperature is 90 F. During cool periods the tortoises are most active
from late morning through early afternoon, during the summer they
exhibit a bipolar activity pattern and are inactive during the hottest
parts of the day.
Hibernation: By mid October the tortoises start excavating shallow
burrows in spots that will be heated by the morning sun. They continue
to feed but do not eat much compared to what they consume when ambient
temperatures are consistently higher. Once daytime temperatures are
consistently in the mid 60s F or lower the tortoises become inactive
(typically the first week of November). They either take shelter under
the building in the protected areas with a substrate of dry cypress
mulch, or remain partially to completely burrowed outside. Often the
tortoises will remain outside throughout the winter (particularly the
females) and the tops of their carapace are exposed to the air during
hibernation (in much the same fashion that many of our native box
turtles hibernate). When removed from these sites and placed inside the
more protected areas under the building within a few days they are back
in their original hibernation site. We have learned to just leave them
be assuming they are better aware of their thermal needs than we are. A
long term captive group of T. (gracia) libera maintained in an adjacent
pen exhibit similar winter behavior patterns. In 2003 the Golden Greeks
emerged from hibernation on 8 March (the same date that the first
Iberian Greek Tortoises and Herman’s tortoises were seen. The first
Russian Tortoises emerged on 14 March that year. All are in separate
pens but on are in the same general vicinity of our property). The
Golden Greek and Iiberian Tortoises also make brief appearances on
unseasonably warm days in November and on December while the Golden
Greek tortoises during warm sunny days continue to emerge to bask for a few
Hours throughout the winter.
Group wintering indoors: Despite being moved in and out, and from pen to
pen on a regular basis these turtles show no sign of stress and seem
content with the routine, often feeding and mating within minutes of
being moved. This is contrary to what some authors have suggested as
they insist that the captive tortoises should be handled and moved as
little as possible in order to assure consistency and to achieve maximum
reproductive success.
Reproduction:
Mating: If the animals in our group are typical adults this taxa is
perhaps the most sexually dimorphic in size of any of the T. gracia
complex. The largest females have a mass that is nearly 2.5 times larger
than that of the largest males. The mating behavior of Golden Greek
Tortoises seems no different from that of other taxa of T. gracea. Males
follow and ram females prior to mounting. Mounted males vocalize but not
as loudly as the larger taxa. Often they just ram other tortoises (males
and females) as a determination of dominance and this frequently appears
to have no direct relationship to reproduction. Mating is stimulated by
moving the tortoises to new quarters, and increased temperatures. Mating
occurs throughout the year in the group that is housed inside during the
winter and from mid-April through late-October in those kept outside
throughout the year. Ramming and associated activities occur mostly at
ground temperatures above 80 F, frequently, and at any time during
daylight hours. Male aggression seems to be limited and minor, but a
number of visual barriers are present in the pens and this probably
decreases male to male interactions.
Nesting and eggs: Females ready to lay paced their enclosures and rammed
other tortoises. Eggs were laid in lawns or when available sand boxes.
Nests were excavated to three inches and the eggs were deposited in
flask shaped holes. The entire nesting procedure lasted up to three
hours. Most eggs were laid in late morning; data on 7 clutches from four
females as follows. Clutch size 2-3 eggs (mean 2.28) Second clutches
from same females laid about 30 days after first (n=2). Most eggs were
produced in June and July although one fertile three egg clutch was laid
in December. Eggs weighed 16.6-19.7 (mean 18.54) grams and measured 37.4
- 42.8 x 27.6 - 29.5 (average 40.23 x 28.55) mm. One clutch was broken
by the female while covering the eggs, a second clutch was broken by us
digging them up. The first four clutches that hatched produced 9 young.
Information on subsequent clutches (post 2003) was not recorded.
Incubation: The first clutch of eggs produced (Dec. 2002) was incubated
under conditions which have proven successful for hatching T. graeca
gracea. These three eggs were fertile and split because of too much
moisture in the vermiculite. Subsequent clutches were incubated on dry
vermiculite at a temperature of 86 +/- 1 F. An air humidity of 60-80%
was maintained in the incubator and eggs were lightly misted on days 40
and 65. This combination of micro environmental manipulations resulted a
100% hatchling success with tortoises emerging between 65-76 days. Young
typically remained in the egg 24-48 hours. Unlike our captive T. g. Iberia,
undetected clutches, and ones left in place in their enclosures failed to hatch.
In that the Iberean Tortoise eggs hatched when left in place and the Golden
Greek do not, we assume factors contusive to successful incubation differ
between these two tortoises..
Hatchlings: Newly hatched young, like the adults, are pale both in shell
color and on their heads and appendages when compared to hatchlings of
the nominate. Hatchlings weighed 13.9-19 (mean 16.3) grams. They
measured 38.3-41.6 (SCL) x 33.2-36.0 (carapace width) mm. Yolk sacks
were well absorbed at the time of emergence from the egg. All hatchlings
started eating with in 24 hours. Several were eating with in hours of
hatching. All indications are the young are healthy and fast growing. We
keep them on moist cypress mulch, the high humidity results in better shell
growth than when the young are maintained on drier substrates, The
young produced from our first two seasons of breeding proved to be all
males and we are now experimenting with incubations temperatures but
the young tortoises produced subsequently are too still too young to sex.
Summary:
This is apparently the first documented successful breeding of Golden
Greek Tortoises in captivity. In that we see no major deviation from the
documented husbandry and breeding of other temperate Testudo graeca
taxa, compared to the vast number of wild caught adults of these turtles
on the market during the late 1990s and first few years of this century,
we assume that our success is based primarily in our initial deworming
and aggressive control of respiratory ailments in the imported stocks.
This conclusion is strengthened by the relatively high mortality rate of
imports. Our two distinct and successful captive husbandry techniques
suggest a wide latitude of conditions in which captive animals can be
successfully maintained once stabilized. Breeding of the group maintained
year round out of doors in a temperate setting deserves additional monitoring,
but preliminary information suggest that this is a viable strategy for
captive groups of Golden Greek Tortoises in appropriate climates and
well drained soils.
Acknowledgement:
We thank the late Dr. Barbara Bonner, who visited our facility in March
2003 and made many useful observations which were of long term value to our
husbandry methods of these and other chelonians in our collection.
Published in World Chelonian Trust Newsletter No.7
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