Head and Neck:
Normally the head
of vertebralis lacks discernable pattern except
for a sometimes
abrupt transition from darker orange tones to lighter yellow
or white tones
as one moves from the dorsal surface of the head to the ventral
surface of
the head. Animals showing bimaris influence will sometimes
exhibit a
light spotted pattern on the dorsal surface of the head. The head
is narrow
and high with the lateral surfaces being remarkably tall and squared
off at
the dorsal and ventral transition. The neck is thin and rather graceful
for
a pituophis. Animals with bimaris influence tend to have
thicker
necks. The first blotch on the neck starts about 9-12 scales back
from the
head.
Captive Varieties
There are
2 captive varieties available in the hobbyist market. The first
is the
normal variety which has been line bred by some hobbyists to accentuate
the
oranges, reds and yellows. Some of these animals have extremely
reduced
black pigmentation on the anterior portion of the body leading some
hobbyist
to refer to them as partially "hypomelanistic" but in
reality
they are normal with the black pigment confined to the posterior
portion
of the animal.
The second variety
goes by a number of trade names such
as: hypomelanistic phase, striped
phase and patternless phase. All these
names refer to the same basic
variation and this has caused considerable
confusion among hobbyists. The
term "patternless" probably comes
closest to discribing this
unusual variation. The animal has a very reduced
dorsal pattern and
typically has no blotches. The ground color ranges from
dark brick red to
orange. One peculiar trait of this variety is that pupil,
iris and scalare
of the eye are jet black giving the snake an unusual "black
eyed"
look.
Range:
Cape gopher snakes have a
range restricted to the southern tip of the Baja
peninsula. This region is
also referred to as the "Cape" region
or the "Cape of
Baja." The exact cutoff of vertebralis
range is ill defined
because of integrading with bimaris to the north.
The general range
of vertebralis roughly extends from La Paz southward
to the tip of
the peninsula. It is interesting to note that there are several
other
unique subspecies of reptiles that have fairly well described ranges
that
roughly coincide with vertebralis - indicating a uniqueness
of
habitat zones at the end of thepeninsula.
Habitat:
The topography, climate, and geology encompassed by
the range of vertebralis
is very complicated and relatively short
distances can bring radical changes
in macro and micro habitats. Within the
range of vertebralis is the
Sierra de la Laguna, a mountain which
towers over 2,134 meters (7000 ft)
and contains pine and oak woodland that
most people would not associate
with the southern extreme of Baja. Other
biological zones found in this
relatively small range are: dry tropical
forest, arid tropical scrub, sonoran
desert and desert shore. Cacti and
rock are dominant features of the landscape.
Overall, the area is dry and
can experience years with almost no rainfall.
At other times the area may
receive deluges from tropical storms and hurricanes
in the Pacific Ocean
and Sea of Cortez. Most reports of vertebralis
taken in situ
have been anecdotal and seem to come mostly from the
arid tropical scrub
zone. This does not mean that vertebralis does
not occur in the
other habitats encompassed by this range. Much of the area
is remote and
very rugged and most sightings have occured at night on the
few developed
roads that lead to tourist areas. I am aware of no field work
having been
done with vertebralis and therefore their daytime habits
are poorly
understood. They are apparently nocturnal and crepuscular and
live a
fossoral existence during the day. Although daytime temperatures
above
ground may be very warm indeed, in the subterranean burrows
where
vertebralis spends its days, the temperatures may be quiet
cool with
high relative humidity. Because of the cooling effect of Pacific
Ocean currents,
night time temperatures can fall rapidly. The net result is
an animal that
is at home in relatively cool micro and macro
environments.
Prey:
Prey preferences of
wild vertebralis are poorly known but one would
assume, based on the
observation of captives, that they probably prey on
a variety of small
mammals with kangaroo rats and deer mice most likely
making up the bulk of
the diet. I have not seen reports of lizards being
included in the diet of
wild vertebralis but this would not be surprising
based on the
abundance of lizards in the area and the natural tendency of
reptiles in
extreme desert climates to capitalize on available food
sources.
In captivity, vertebralis
readily feed on lab mice,
deer mice and lab rats and will feed on both live
and pre killed food items.
They appear to have relatively high metabolisms
and do not put on weight
as easily as other Pituophis ssp. Feeding at too
high temperatures, i.e.,
27.8C (82F), can cause regurgitation syndrome.
Feeding large prey items
can also cause regurgitation syndrome. This can
usually be corrected by
fasting and then resuming feeding with very small
food items. Typically,vertebralis
tend to be a more slender
Pituophis and attempts to bulk them up often result
in the onset of
regurgitation cycle.
Captive Behavior
Cape
gophers have variable behaviors in captivity with hatchlings being
very
easily agitated and adults being more sedate. They are however,
somewhat
nervous, active animals and prefer a quiet, low stress captive
environment.
Hide boxes are preferred by some individuals and completely
ignored by others.
Some adults are prone to mood swings that are often
initiated and then exacerbated
by keeping the animals at too high
temperatures. A common mistake of hobbyists
keeping vertebral is for
the first time is to keep them too warm
- an assumption often based on what
most hobbyist would assume are "natural"
conditions. Most feeding
and behavior problems can be alleviated by lowering
the cage temperature of
captive vertebralis to about 25.5C (78F)
to 26C (79F). It is not
recommended that vertebralis be given a basking
spot unless the
ambient cage temperature consistently falls below 25.5C
(78F). Water should
be made available atall times in a wide mouth dish
that is not prone to
spilling. Cage conditions should be kept dry.
Animals for which breeding is intended should begin brumaiton
in
late November and end brumation in mid to late February.Temperatures
that
fluctuate between 12.8C (55F) and 18.3C (65F) during this period are
ideal.
After the animals are removed from brumation, copulation may
begin
immediately or may begin anytime over the next 5 weeks. Females
usually
breed before their first shed in the spring. Eggs are laid
approximately
45 days after the onset of copulation. Typical clutch sizes
range from 5
to 10 eggs. Females will lay eggs 7-10 days after their
pre-lay shed. Females
may not appear gravid until 3-4 days prior to laying
- the eggs are apparently
not hydrated until right before laying to
conserve water. Well fed females
are capable of double clutching. Eggs are
incubated in the typical colubrid
fashion on slighty moist vermiculite and
take approximately 70 days to hatch
at 27.8C (82F). Hatchlings are robust
and active upon hatching and ususally
feed readily on live pink mice
following their first shed.
Literature
Cited:
Stebbins, Robert C. 1985. A Field Guide
to Western Reptiles
and Amphibians. Houghton Mifflin Company, Boston. 336
pp.
Wright, Albert H. and Anna A. 1957.
Handbook of Snakes
of the United States and Canada, Vol.II. Comstock
Publishing Associates,
Ithaca and London. 1105 pp.
Mehrtens, John M. 1987. Living Snakes of the World.
Sterling
Publishing Co., New York. 480 pp.
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