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THE TORTOISE VOLUME 1 ✯ NUMBER 3 2014
TORTOISE
THE
VOLUM E 1 ✯ NUMBER 3
A PUBLICATION OF THE TURTLE CONSERVANCY
A Leisurely Journal of
Travel and Research
THE
MEXICAN
TORTOISE
PROJECT
by Taylor Edwards
A “Sinaloan” type desert tortoise in Tropical Deciduous
Forest at Reserva Monte Mojino, Sonora.
TAYLOR EDWARDS
I
awake in my tent to the sound of macaws pass-
ing overhead. I poke my head out and see a
small highway of leafcutter ants carrying metic-
ulously cut pieces of a nearby bush. A monstrous
spiny-tailed iguana watches me from his perch on
an adjacent strangler g.
is is not exactly the scene you might expect
to nd yourself in on a quest for Desert Tortoises,
but our search has led us here, to the tropical decid-
uous forest on the southern edge of the state of So-
nora, Mexico. It bears little resemblance to the red
clis of southwestern Utah or the sun-cooked creo-
sote ats of the Mojave Desert in California. And al-
though the columnar cactus and thorny acacias are
a bit familiar if you live near Tucson, Arizona, the
towering kapok trees and boa constrictors quick-
ly overshadow any resemblance to home. Because
Desert Tortoises occur in all of these places, it begs
the question of how this came to be.
In 2011, the Desert Tortoise was redened
as two separate species: Agassiz’s Desert Tortoise
(Gopherus agassizii) and Moraa’s Desert Tortoise
(Gopherus moraai). Gopherus moraai is found
in Arizona and Mexico, in the Sonoran Desert. Al-
though the two species are rather cryptic in their
morphology, meaning they appear very similar to
the untrained eye, they are behaviorally, morpho-
logically, ecologically, and genetically distinct. e
U.S. Fish and Wildlife Service now considers G.
moraai a candidate for listing under the Endan-
gered Species Act. In the Sonoran Desert approx-
imately two thirds of the range of the Desert Tor-
toise is in Mexico but virtually no research had been
conducted there. erefore, to truly understand the
conservation status of tortoises in the Sonoran Des-
ert we needed to go south of the border.
Driven by a dearth of knowledge on the status
of desert tortoises south of the U.S. border, a team
of Mexican, Canadian, and American collaborators
began to study them in Mexico in 2005. Like all
great adventures, strong and determined personal-
ities drive ours. Mercy Vaughn and Alice Karl, two
indefatigable tortoise experts, fuel the project. is
cooperative eort focuses on crucial aspects of Des-
ert Tortoise health, genetics, general biology, and
ecology, and has included radio-telemetry, focal
and behavior studies, morphometrics, and blood
sample collection. For my part, I am investigating
the genetic diversity of tortoises in Mexico and their
relationship to U.S. populations.
e biggest resource was, and still is, volun-
teers. Collecting trips were (and still are) the two-
week vacation you look forward to the rest of the
year. Since the project’s inception in 2005, we have
had over 75 volunteers join us in the eld in Mex-
ico. ey bring their vehicles, their gear, and their
blood, sweat, and at times tears. In return they gain
a new appreciation for an animal we all thought we
knew but is really still a mystery.
Getting to the tropical deciduous forests of
southern Sonora does not necessarily require a trip
to the airport. In fact, it is easiest done by car (at
least if you are already starting in the southwestern
U.S. (California, Arizona, and Nevada) where most
Desert Tortoise biologists are located. From Tucson,
it is only an 8 hour and 40 minute drive, according
to Google Maps. However, I’ve never made it quite
that quickly. Less than 280 miles of travel is consid-
ered the “Hassle Free Zone,” a poorly worded cam-
paign by the Sonora Oce of Tourism to encourage
U.S. travelers to feel comfortable driving to tourist
destinations like Puerto Peñasco or San Carlos. For
us, it implies that the trip is a hassle.
Travel along the major thoroughfares in Mex-
ico is actually quite easy as long as the highway is
open. But such is not always true. On multiple oc-
casions the Yaqui Indian tribe has staged demon-
strations that blocked trac along Federal Highway
15. is is generally due to civil protest between
the tribe and the Government of Mexico over wa-
ter rights. Sometimes it is possible to skirt around
the protesters through agricultural lands, but other
times it requires a long detour to the Federal High-
way 16 instead. is has become such a regular de-
tour that during our last visit in 2013 the local radio
station regularly announced if cars and trucks were
being let through at any given time, as if it were the
regular morning trac report.
Other than being a bit unpredictable, the drive
from Tucson to Alamos is an amazing journey that
follows the story of the Sonoran Desert and the evo-
lutionary history of the tortoise. e upland habitat
surrounding Tucson is characterized by iconic sa-
When friends ask me if it is
dangerous to work in Mexico I
have to say yes, but not at all for
the reasons they assume.
THE TORTOISE ・
guaro cactus reaching for the sky and green-barked
palo verde trees with little green specks that are
barely recognizable as leaves. However, one of the
most fascinating aspects about the Sonoran Desert
is its relatively recent transformation into the as-
semblage of species we observe today as the Arizo-
na Upland Sonoran Desertscrub. Just 12,000 years
ago it was a very dierent ecological community.
Prior to and during the Pleistocene (12,000 to 2.5
million years ago), the Sonoran Desert showed ev-
idence of having a more “tropical” ora and fauna
that extended throughout the region. It was not a
desert at all; fossil evidence of a boa constrictor
found at the mouth of the Colorado River dated to
the early Pleistocene, and crocodiles and capybaras
that once occurred in east-central Sonoran would
certainly not nd a home in today’s arid landscape.
Tropical Beaded Lizards and Boa Constrictors are not
usually associated with Desert Tortoises, but in the
southernmost part of their Mexican range they share
the same ecological niche.
KERRY L. HOLCOMB KERRY L. HOLCOMB
MAXIMILIAN MAURER
MEXICO
PACIFIC OCEAN
UNITED STATES
LOS ANGELES
CARBORCA
HERMOSILLO
SINALOA
RANGE OF THE
AGASSIZ’S DESERT TORTOISE
RANGE OF THE
MORAFKA’S DESERT TORTOISE
30˚
240˚ 245˚ 250˚ 255˚ 260˚
35˚25˚
0100 200 300 MILES
Alice Karl shows project volunteers how
to perform health assessments and take
morphometric measurements on a tor-
toise at Reserva Monte Mojino, Sonora.
THE TORTOISE ・
TAYLOR EDWARDS
History explains the remnant populations of jaguars
and ocelots here. Around 12,000 years ago, during
the early Holocene, it was likely wetter and cooler
than it is today, and the landscape was dominated
by woodlands that were replaced by desertscrub as
the region became warmer and drier. e Sonoran
Desert is the youngest of the North American des-
erts but also has the greatest biodiversity.
Staring out the car window, the changing des-
ert landscape might not be immediately evident,
but relatively soon aer crossing the border into
Mexico the silhouettes of saguaro cactus on the
horizon become mixed with the grander cardón
cactus as well as organ pipe cactus. e weedy Jatro-
pha (or limberbush) of the Tucson Mountains rise
into trees and ll the air with their fragrant aroma.
It is still the Sonoran Desert, but it is recognizably
dierent just a few hours to the south. One of the
goals of our project was to assess the connectivity
of Arizona and Mexican populations of tortoises
by measuring how much genetic exchange occurs
between them. is is called gene ow. Tortoises
may move slowly but radio-telemetry studies sug-
gest they can be motivated to move long distances.
A tortoise from Saguaro National Park on the out-
skirts of Tucson was tracked making an extraordi-
nary 20-mile journey over the course of two sea-
sons from one mountain range to another. During
her adventure she encountered railroad tracks and
roads and eventually researchers physically moved
her across the interstate when she became stuck
between the frontage road and the constant ow
of trac. She was named elma aer the movie
character because she was an adult female who just
picked up one day and le. Later, from the same
park another adult female made a similar trek away
from her home but in the opposite direction. She
was named Louise.
It was not until 2011, six years aer the Mex-
ican Tortoise Project began, that we got to sample
areas in Mexico just south of the border. We al-
ready had a collection of samples approaching the
border on the U.S. side, but concerns about safety
delayed our sampling in Mexico. We ended up sam-
pling several sites in the mountains surrounding
Ciudad Caborca. If you Google Image “Caborca,
Mexico” pictures of burned human carcasses with
their heads, arms, and legs removed quickly ll the
screen. e drug violence in Mexico is real; howev-
er, the risk is easily reduced if you are a smart trav-
eler. e problem is not that tourists (or biologists)
are particularly targets in the cartel violence near
the border cities of northern Mexico, rather a team
of biologists working in Mexico tends to travel in a
large caravan of 4x4 trucks and SUVs, which is also
how cartels travel; thus we might call unwanted at-
tention to ourselves. To reduce the risk of problems
we tried to travel only during the day, checked in
with local authorities, and worked on private “ran-
chos” where our presence was known, access to the
areas was limited, and we were oen accompanied
by ranch hands (vaqueros) who know the land and
most importantly know where to nd tortoises.
All this preparation was only possible because our
Mexican collaborators not only helped facilitate our
permits and land access, but also coordinated our
eorts to make the trips safe and productive.
When friends ask me if it is dangerous to work
in Mexico I have to say yes, but not at all for the
reasons they assume. When conducting eldwork, I
am much more fearful of the heat and the bees than
the drug cartels. In the dry heat of the desert, Afri-
canized bees are drawn to even the smallest drop of
water. ey surround the mouthpiece of your Cam-
elBak and ock to the sweat covering your back.
Open the cooler in the back of your vehicle and it
becomes a beacon for bees to gather. It is inevitable
that some of the crew will get stung on any outing,
but the greater danger of disturbing a hive is always
looming as you peer into the rock crevices looking
for tortoises. e constant presence of killer bees
is coupled with the greater threat of the overbear-
ing heat. It was not uncommon to measure ground
temperatures greater than 150 degrees Fahrenheit
during our aernoon siesta (we look for tortoises
early in the morning and late in the aernoon). Al-
though our crew consisted of extremely eld-wor-
thy biologists — many who spent the months prior
to the Mexico eld trips working full time in the
heat of the Mojave Desert — the heat can be over-
whelming for even the most experienced biologist
in Mexico, especially in August and September with
the added humidity of the monsoon season.
Signs of heat exhaustion include headaches,
dizziness, cramps, and even vomiting. We had sev-
eral incidents where people could not make it past
the morning survey before hitting these incapaci-
tating symptoms. e worst was when one of our
crew members experienced heat stroke; I could see
she was disoriented upon returning to the vehicles,
and as I tried to engage her in conversation she
fainted. I caught her in my arms as she went into
seizures. We were hours from a hospital so I imme-
diately put ice on the back of her neck to cool the
blood owing to her already overheated brain and
we got her into an air-conditioned vehicle. Once
(above) Where the desert meets the sea; a view of Isla Tiburón in the Sea of Cortez as seen from one
of the coastal desertscrub study sites in the Seri territory of western Sonora. (below) The research crew
pauses near a giant “tescalama” (strangler g) while searching for tortoises in the Sierra de Alamos Eco-
logical Reserve.
THE TORTOISE ・
TAYLOR EDWARDSTAYLOR EDWARDS
she gained consciousness, we had her eat salt along
with drinking small amounts of water. is time we
were lucky and our overheated crew member fully
recovered, but, needless to say, their trip ended ear-
ly. is exemplies how dedicated our volunteers
are to work in these conditions. Sound like a fun
way to spend your summer vacation?
e Mexicans we work with carry table salt and
limes with them in the eld, along with their wa-
ter. When they stop for a rest break, they lick some
salt, squeeze key lime into their mouths, and take a
sip of water. It is like a tequila shot but without the
booze. Although we tend to think of the biggest fac-
tor in experiencing heat exhaustion as being a lack
of water, it doesn’t matter how much water you have
if your water is warm and your body (and brain)
reaches more than 104 degrees Fahrenheit and
can’t cool down. In addition, you lose a tremendous
amount of water and salt through your sweat. Even
if you are “hydrated,” your salt balance is critical
for normal muscular and neurological functions.
is is why athletes drink Gatorade — to maintain
these vital electrolytes. e limón y sal taken by our
Mexican colleagues achieves this same objective —
and whatever is not used in the eld can be passed
around with the tequila later that night.
In the lab I have these hard-earned tortoise
genetic samples collected near the border, and I
have assessed their relationship to samples in Ar-
izona. Over the evolutionary history of a Desert
Tortoise, there was no international border. I have
found a continuum of genetic relatedness between
desert tortoises as far north as Kingman, Arizona,
(Hualapai foothills) to Hermosillo, Mexico (a span
of more than 500 miles). is is an unusually large
distribution for any species with a pending Endan-
gered Species Act conservation status. Of course
tortoises do not occupy this entire space but are
instead distributed across the landscape in small
patches of habitat in the foothills and uplands de-
scribed earlier. Each of these small populations is
seemingly isolated from other populations except
for the long-distance movements of a few individ-
uals like elma and Louise. Successful attempts to
move from one population to another may be few
and far between, but in perspective of a tortoise
lifespan, only one such movement that results in
the transfer of genes from one population to anoth-
er per generation (estimated as every 25 years for a
Desert Tortoise) is enough to maintain genetic con-
nectivity among populations. is may be particu-
larly important for the maintenance of small popu-
Although the tortoise may be a threat-
ened species, it is nowhere near the
level of endangerment of the culture
and language of the Comcáac people.
© GRACIELA ITURBIDE
Found tortoise shells among other things adorn the wall of
a ranch house at Rancho La Candelaria north of the El Viejo
Mountains in northern Sonora.
TAYLOR EDWARDS
lations that have declined as a result of drought or
stochastic processes. As tortoises are long-lived and
slow to mature, the recovery of a declining popu-
lation may actually be dependent on immigration
from neighboring populations, as the time to re-
cover to viable population levels naturally may take
longer than the reproductive rate for a small popu-
lation can accommodate.
Until now tortoises have been moving across
the Sonoran Desert landscape like this for thou-
sands of years. e recent proliferation of man-
made barriers like highways, canals, agricultural
lands, urban areas, and now border walls have oc-
curred within only a couple of Desert Tortoise gen-
erations. Tortoises are just one of the species across
the Sonoran Desert that are greatly aected by habi-
tat fragmentation, along with bighorn sheep, cactus
ferruginous pygmy owls, and pronghorn. But tor-
toises are dierent in that the time it will take to
see the eects are much longer because they are so
long-lived. On one hand, their natural population
structure does not yet exhibit obvious detrimen-
tal eects. On the other hand, once it does exhibit
problems recovery will proceed very, very slowly —
if at all. Such issues are relevant to the short-term
politics fueling the physical construction of the bor-
der wall and the long-term eects it will have on
our natural heritage.
Coming back to our driving excursion into
Mexico, if we take a side trip to the west, to coastal
Sonora, we nd an interesting piece of the puzzle.
Here we sampled tortoises on the Seri lands, the
home of the Comcáac people, an indigenous group
of historically seminomadic hunter-gatherers who
are at home both in the desert and on the sea. In
Gary Nabhan’s wonderful ethno-herpetological ac-
count of the Comcáac, Singing the Turtles to Sea, he
describes a people intimately connected to the land
and more specically, the reptilian inhabitants they
share it with. e Comcáac have been implicated in
introducing chuckwalla and other animals to many
of the islands in the Sea of Cortez, presumably to
maintain sources of food if their panga (shing
boat) becomes stranded during inclement weather.
e Comcáac culture also maintains an intimate re-
lationship with Desert Tortoises, and they inevita-
bly moved Desert Tortoises around their territories
as well. A variety of taboos likely helped regulate
their over-exploitation, however.
In 2010, we had the opportunity to assess the
tortoise population in the Seri territory of western
Sonora, Mexico, and we visited several sites on the
mainland and two sites on Isla Tiburón with our lo-
cal Seri host, Ernesto Molina. is area consists of a
magnicent representation of Sonoran desertscrub
that includes a beautiful mosaic of saguaro, organ
pipe, senita, and cardón columnar cactus. Part of
the impetus of surveying here was to revisit sever-
al areas where tortoise surveys were conducted in
2001 and 2002 in response to reports by the Seri
Indians of high Desert Tortoise mortality. At that
time, the survey team led by Mercy Vaughn, Felipe
Rodriguez Garcia, Gary Nabhan, and Patricia West
found very high rates of recent mortality at all sites
that raised concerns about the status of the Mexi-
can populations of the species. e eort in 2010
was an opportunity to revisit these sites, and, un-
like the rst survey eort, we had permits to collect
blood samples for further disease testing. Although
we did nd tortoise carcasses, the good news was
we did not observe nearly so many as were found
in 2001 to 2002 or other signs of recent mortality.
In addition, we found very limited incidence of up-
per respiratory tract disease that occurs, sometimes
commonly, in populations in the United States.
I did nd, however, some intriguing genetic dif-
ferences that suggest an increased amount of genet-
ic diversity in this coastal region. Unique lineages
found on Isla Tiburón (that potentially predate the
arrival of humans to the New World) suggest that
tortoises naturally immigrated here during glacial
periods when lowered sea levels allowed passage.
e Seri may have moved animals as well, but these
likely mirror natural patterns of movement where
the tortoises are closely related to each other in the
region anyway. e continued presence of tortoises
in these coastal areas, despite most of Sonora expe-
riencing oscillating vegetation (tropical, mesic, des-
ert) during glacial minima and maxima, suggest it
may have been an oasis or refugia for desert-adapt-
ed plants and animals. Further up the coast, in the
Gran Desierto and isolated Pinacate volcanic range,
it appears that desert conditions may have been
maintained while the rest of Sonora transitioned
from tropical forests to woodlands and back again
before warming and drying nally sculpted the cur-
rent range of the Sonoran Desert.
e genetic connectivity of tortoise popu-
lations spans from Kingman, Arizona, through
Hermosillo, Mexico, and is suggestive of a recent
population expansion across the emerging Sonoran
Desert from these coastal refugia over the last
100,000 years. is expansion and contraction like-
ly occurred many times over the evolutionary his-
tory of this species, and we are only witnessing the
most recent event. e genetic diversity captured in
Felix García Caballero, Head of Field
Operations for Reserva Monte Mojino assists
researchers in nding tortoises in the reserve.
TAYLOR EDWARDS
these southern coastal ranges suggests that this may
be the source for the entire Sonoran Desert Tortoise
population and likely other species as well.
Although the tortoise may be a threatened spe-
cies, it is nowhere near the level of endangerment of
the culture and language of the Comcáac people. For
thousands of years, the Comcáac and their ancestors
acted as stewards of the land and its inhabitants. Now
less than 1,000 native Seri speakers remain, and their
vast knowledge of Desert Tortoises and the desert
ecosystem may soon be lost. Now consider that West-
ern scientists like myself are only beginning to under-
stand this unique region.
Back on Interstate 15 and heading south, a big
change happens aer leaving Hermosillo, about 250
miles south of Tucson. Here we start to see thornscrub.
While thornscrub forests may appear like a landscape
in transition, it truly is a unique vegetative communi-
ty unto itself. I’d be happy to describe it to you if any of
the experts on Sinaloan ornscrub could describe it
to me rst. It looks like someone let only the most ag-
gressive and most dicult-to-pull weeds overtake the
garden, and then the weeds grew to massive propor-
tions. Biologists can describe it as consisting of mainly
short trees, shrubs, and cacti with many species being
“thorny.” It is nearly frost-free and thus temperature
limits its latitudinal and elevational distribution; and
it has alternating wet and dry seasons. However, my
favorite description is from Vaughn who, instead of
the “wait-a-minute” bush acacias you encounter in a
typical desert, describes walking through thornscrub
as “wait-a-couple-of-minutes” bush.
Here, something magical happens. We do not
cross a major river or go over a mountain, we just
look out the window and the vegetation changes.
And so do the tortoises. e tortoises occupying
these thornscrub forests and continuing into the
tropical deciduous forests where we started our story
are very dierent from the tortoises we le behind in
the desertscrub — about 5 to 6 million years dierent.
is is as divergent genetically as what is observed
between Desert Tortoises in the Mojave Desert of
California and those in Arizona that are recognized
as separate species. However, the Mojave/Sonoran
split is somewhat expected because these species are
separated by the Colorado River, which prior to that
was an inland sea called the Bouse embayment. is
is a classic example of what biologists call allopatric
speciation. What we are seeing in the transition from
desertscrub habitat to thornscrub habitat to a casual
passerby is nothing more than a change of scenery. So
what factors are driving this tremendous amount of
dierentiation?
Answering this and related questions is
enough to earn someone a Ph.D., and I decided
that someone should be me. We have dubbed these
southernmost Desert Tortoises “Sinaloan” Tor-
toises and our investigation so far has revealed be-
havioral and morphological dierences as well as
genetic distinction. Are we dealing with a distinct
species, cryptic to science until now? Very likely.
Most intriguing, however, are a few areas of over-
lap where we nd both kinds of tortoises, Sonoran
and Sinaloan, and we observe limited mixing (or
hybridization) between the types. My role as an
evolutionary biologist is to tease apart the evolu-
tionary history of this animal, investigate its ori-
gins, and help to dene its evolutionary potential.
Has the Sinaloan type just been isolated in its own
tropical refugium during long periods of climate
change and is only now reuniting with its desert
cousin, yet to determine their compatibility aer
their long absence? Or, have these two lineages
been in contact time and time again and is natural
selection against their intermixing slowing forcing
them apart? Wolves and coyotes, which diverged
from a common ancestor 3 to 4 million years ago,
are capable of interbreeding and sometimes do;
it may even be benecial to introduce some new
genetic stock into the population once in awhile.
However, these canids obviously still maintain
distinct lineages, ll dierent niches, and retain
unique adaptations. Is this going on between So-
noran and Sinaloan Desert Tortoises? One thing
we do know from Darwin is that speciation gener-
ally takes a long, long time, and in the present we
are only seeing a snapshot of that process.
Even to a novice, the Sinaloan Tortoise imme-
diately appears different. They can be strikingly
yellow or orange, and their carapace is flatter and
squarer than what is seen in typical Sonoran indi-
viduals. The scales on their forelimbs frequently
protrude and can be very spiky. Is this just natu-
ral variation or are these adaptations selected for
this more tropical environment? Phil Rosen, one
of the project collaborators, hypothesizes this ar-
mor may be a defense against predators living in
these tropical regions. They do share their home
with jaguars, after all. We still have a lot of ques-
tions about what Sinaloan Tortoises eat, how
social they are, what their home range is, their
reproductive cycle, and even how far south their
distribution extends. Our southernmost sample
was collected south of the Rio Fuerte in Sinaloa.
To h o ld o n e i s t o k no w y ou a r e h ol d in g s om e -
thing special.
Defining these taxonomic distinctions is
necessary for effective conservation of tortoises
inside and outside the U.S. Our goal is to assist
in the designation of management units for the
entire range of the Desert Tortoise, including
Mexico, so that conservation efforts can be ap-
plied with specificity to each area. We can also
use genetic data to determine the extent to which
sampled populations have experienced popula-
tion declines and therefore which populations
are most vulnerable to the combined effects of
barriers to gene flow and loss of genetic variabili-
ty. There is growing interest in understanding the
natural history of Desert Tortoises in Mexico, so
that we can apply long-term approaches to man-
agement and conservation. Mexico is faced with
a privileged situation in that we can make efforts
to protect tortoises before they are at the edge of
extinction. Unfortunately, many species do not
receive this kind of valuable research attention
until after their populations have declined.
As a result of this ongoing research, I was
asked to co-author an article in Especies mag-
azine, highlighting conservation concerns of
tortoises specifically in Mexico, for a Mexican
audience. Especies is a popular newsstand pub-
lication with glossy photos and relatable text. I
was thrilled to reach this audience and although
I have published many peer-reviewed scientific
articles, I believe my biggest impact as a conser-
vation biologist can come from this type of me-
dia. The article was published in the summer of
THE TORTOISE ・
2012, and a tortoise even graced the front cover. I
happened to be traveling with my family in Mex-
ico when the issue came out, so I tried to obtain
a copy. In the small tourist town where we were
staying I was approached by a street vendor try-
ing to sell ponchos and blankets, and I told him
in my broken Spanish that what I really wanted
was “Esto, por favor,” and I showed him a picture
of the cover. He looked at it and said, “Un minu-
to,” and he took the image to some other people
in the back of his store. Although what I wanted
was the magazine, when he returned he stated,
“You want a Tortuga? I can get you a Tortuga out
in the desert.”
So, unfortunately it is easier to buy a pro-
tected species of tortoise in Mexico than a con-
servation magazine about tortoises. This is too
frequently the punchline of conservation. What
I do know from my research over the last eight
years is that Mexico has something special, some-
thing worth saving. Perhaps we will name a new
species from our work or just define the Mexican
populations as unique. Regardless, tortoises are
a treasure of the Southwest and in their history
is the history of the Sonoran Desert itself. Win-
ston Churchill said, “The farther backward you
can look, the farther forward you are likely to
see.” And although he was certainly not referring
to tortoises, my investigation into these almost
ageless creatures has given me much insight into
what role we all play in preserving the future of
the desert Southwest.
A “Sinaloan” type desert tortoise outside its rock burrow
in the Sierra de Alamos Ecological Reserve.
Researchers prepare to remove the radio telemetry unit
from one of the study animals at the Sierra de Alamos
Ecological Reserve.
TAYLOR EDWARDS
TAYLOR EDWARDS
TURTLE CONSERVANCY
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Rather like a National Geographic DEDICATED EXCLUSIVELY TO these wonderful animals.
I totally enjoy it and look forward to every issue.”
— Dr. Russell Mittermeier - PresidentConservation International