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264 IGUANA  •  VOLUME 13, NUMBER 4  •  DECEMBER 2006 PASACHNIK

The author processing a ctenosaur in the mangrove swamp on Utila.

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Mesoamerica is one of the most biologically diverse areas in
the world. Iguanid lizards comprise a conspicuous com-

ponent of this diversity, largely due to the species-rich genus,
Ctenosaura. This genus encompasses 17 distinct species (more
than twice as many as the second most diverse genus, Cyclura).
These lizards are threatened with extinction by habitat destruc-
tion and fragmentation, over-harvesting, pollution, and expor-
tation for an illegal pet trade (four of the five largest threats to
biodiversity). In 2004, ten species in this genus were Red-listed
by the IUCN. Four of five species listed as critically endangered
form the Ctenosaura melanosterna clade. In order to address the
high degree of intra-generic diversity, gain an understanding of
the threats faced by these critically endangered species, and aid
in their protection, I plan to do a multi-scale molecular evalua-
tion of the clade and its wide-ranging and sympatric congener,
C. similis.

One principal goal of my research is the construction of a
molecular phylogeny of the Ctenosaura melanosterna clade,
which occurs along the Caribbean versant of Honduras and
Guatemala and on the Honduran Bay Islands. When added to
recent studies of the southern sister clade, the C. quinquecari-
nata complex, this work will complete the phylogenetic analysis
of ctenosaurs in southern nuclear Mesoamerica.

A second component of this project will address the threat
that habitat destruction poses to Ctenosaura bakeri, endemic to

the Bay Island of Utila, by evaluating the degree and direction
of genetic introgression with C. similis. These hybridization
events may result from a novel overlap in the ecological distri-
butions of these species that resulted from habitat destruction.
A detailed management plan will recommend methods of pre-
serving the genetic integrity of C. bakeri.

The third portion of this investigation concerns the colo-
nization by Ctenosaura bakeri, C. similis, C. melanosterna, and 
C. oedirhina of the Bay Islands, Cayos Cochinos, and various
islets in the Caribbean Sea bordering Honduras. This will allow
for insight into evolutionary rates and patterns within this clade.
Additionally, due to ecological and hybridization threats that 
C. similis poses to C. bakeri, dating the arrival of the former on
Utila will be necessary to determine if it is an invasive species.

During the spring and summer of 2006, I spent six months
collecting data on Ctenosaura melanosterna, C. bakeri,
C. oedirhina, and C. similis populations throughout their respec-
tive ranges in Honduras. The goal of this preliminary report is
to discuss the success of collecting DNA samples and the cur-
rent status of the populations of these species. Later reports will
discuss my molecular findings.

Southern Honduras (March)
Department of Choluteca.—Along the main highway, we
encountered children selling C. similis and Iguana iguana and

Ctenosaurs of Honduras: 
Notes from the Field

Stesha Pasachnik

Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville

Photographs by the author except where noted.

IGUANA  •  VOLUME 13, NUMBER 4  •  DECEMBER 2006 265CTENOSAURS OF HONDURAS

�

Destruction of what had been a mangrove stand southeast of the canal
on Utila.

The author (left) and Hadas Grushka, a volunteer from Israel, noos-
ing ctenosaurs from an incomplete foundation.

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were able to obtain tissue samples from four C. similis. These
children told us that, in an effort to be sustainable, they only
catch males. We could not confirm that contention, but I see no
reason for them to lie, since hunting iguanas at all is illegal. In
an area locally called La Bonanza, we again encountered children
selling C. similis and I. iguana. We obtained tissue samples from
three more C. similis, before traveling north along a dirt road
toward the town of El Triunfo, where we caught a juvenile
ctenosaur. Given the locality, this should have been C. similis,
however, it looked strikingly like C. flavidorsalis. A genetic sam-
ple and subsequent molecular analysis should resolve this mys-
tery. Inspired by a photo of what looked like C. quinquecarinata
from this area (sent to me by Dr. Thomas Akre), I asked locals
about this possibility. Apparently, C. quinquecarinata did and
may still occur in this area, although we found no individuals.

Department of Valle.—In an area known as San Juan Pali,
we encountered a man carrying a bag of ctenosaurs. We obtained
tissue samples from four C. similis, but were unable to determine
the sex of these individuals due to their condition. Locals at Playa
Blanca helped us catch two additional lizards, one of which
appeared to have been poisoned, a local technique for ridding
gardens of iguanas. In San Pablo we hired a boat to take us to Isla
del Tigre and Isla Exposicion. Although we saw many C. similis
on Isla del Tigre, we were unable to catch any. Our visit to Isla
Exposicion proved more successful. Aided by four local teenagers,
we caught three male C. similis. Apparently, all of the sizable
islands in the Golfo de Fronseco support ctenosaurs.

Hunting pressures on ctenosaurs in these southern depart-
ments are intense. Hunters have little fear of being caught.
Additional molecular work from this area is desperately needed
to determine if the C. similis in the area represent a unique gene
pool. Intense field and molecular work also are needed to deter-
mine if either C. flavidorsalis or C. quinquecarinata are present.

Northern Honduras
Department of Cortez (July).—Locals in San Pedro Sula told us
that ctenosaurs are not sold in markets due to the presence of
law enforcement. We did, however, encounter both I. iguana
and C. similis being sold along the highway north of the city. We
obtained a tissue sample from one adult female C. similis. In
Puerto Cortez, we searched for ctenosaurs in areas where they
are normally sold, only to be told that it was the wrong season.
However, one roadside “store” had “iguana” meat for sale. We
could not determine what type of iguana this was due to its con-
dition. Traveling west along the coast toward Omoa, we encoun-
tered many C. similis, but were able to obtain tissue from only
one individual. In the small Garifuna village of Travesia, locals
told us that they normally have many iguanas for sale, but it was
not the right season for hunting iguanas.

Department of Atlantida (June and July).—In the towns of
Miami and Tornabe, we obtained tissue from seven C. similis.
Along the road from Tornabe to Miami and in the village of
Miami, we saw many hatchlings, indicating that this is a very
stable population, despite the presence of local hunters. In

266 IGUANA  •  VOLUME 13, NUMBER 4  •  DECEMBER 2006 PASACHNIK

Ctenosaura oedirhina from Barbareta, Roatan.



IGUANA  •  VOLUME 13, NUMBER 4  •  DECEMBER 2006 267CTENOSAURS OF HONDURAS

Miami, a grove of large Red Mangroves (Rhizophora mangle)
provides habitat for many adult C. similis.

We hired a small boat to take us into the Punta Sal
National Park, where we visited the areas of Puerto Carib and
Cocolito. We caught seven hatchlings in Puerto Carib and six
more in Cocolito. Additional molecular work is needed, but the
population in the park seems to be reproducing well. The lack
of encounters with adults was probably attributable to the very
dense vegetation, although we cannot rule out hunting pressure.

Department of Colon (July).—Our time here was split
between the coastal regions, where C. similis occurs, and the
Valle de Aguan, where both C. melanosterna and C. similis occur.
We obtained eight C. similis tissue samples from Sambo Creek,
between La Ceiba and Trujillo. We stopped in many different
towns and asked about ctenosaurs in markets, but were told each
time that selling iguanas is illegal. Ctenosaura similis appears to
be thriving in the gated area at Puerto Castillo. Guards, most
likely representing the Standard Fruit Company, apparently pro-
vide protection for the ctenosaurs in this area. We easily caught
three individuals. We then entered the Naval Base, where C. sim-
ilis was similarly abundant, although catching them was impos-
sible. My impression was that they are harassed but not hunted.

Along the road from Puerto Castillo and around Casa
Kiwi, we found a good number of juvenile C. similis, the latter

a result of protection provided by the New Zealand owners. We
asked to collect tissue samples, but were told that no iguana
could be harmed for any reason. Although disappointing for our
study, such an attitude should help preserve C. similis in the area.
We acquired two tissue samples west of Trujillo, one subadult
female in the town of San Antonio and one sample retrieved
from the tail of a C. similis, lost as it escaped into a hole.

Ctenosaura similis appears to be much less threatened in
these northern coastal areas than in the south. Northern popu-
lations seem to be reproducing at good rates, and individual
property owners seem to be taking an active interest in their
preservation. However, illegal hunting does occur, but popula-
tions seem to be handling this threat.

In the Valle de Aguan, we acquired genetic samples from
eight C. melanosterna and seven C. similis. Four C. melanosterna
(two juveniles and two hatchlings) and six hatchling C. similis
were captured north of the Río Aguan in an area known as Agua
Caliente, and four additional C. melanosterna (three sub-adult
males and one hatchling) and one hatchling C. similis were cap-
tured south of the river in the area around Arenal. The situation
in this area is dire. Hunting pressure is greater than I have seen
anywhere else, with the possible exception of southern
Honduras. The threat is aggravated by the fact that this is the
only continental area where C. melanosterna occurs. I did not see
a single adult C. melanosterna and saw very few hatchlings.
Hatchling C. similis were abundant, and the timing was such
that hatchling C. melanosterna should also have been prominent
— if they are indeed breeding. Given the reduced range of C.
melanosterna and the anthropogenic factors involved, this popu-
lation could be extirpated within a few years if action is not taken
immediately. The Honduran government in past years was work-
ing on a reserve for endemic species. This effort, headed by Paul
House, was to include a breeding program for C. melanosterna.
This project is no longer funded and is at a standstill. The only
alternative is a coordinated effort by international organizations
and the COHDEFOR office in Olanchito, which recently has
established a protected area in the Valle de Aguan, and is in the
process of building a visitor/research center on site. At present,
guards watch over this area, and I strongly recommend that a
breeding program be implemented within that reserve.

Cayos Cochinos (June)
The Cayos Cochinos Archipelago is protected by the Honduran
Coral Reef Foundation (HCRF), which has set up a National
Marine Reserve that encompasses all of the islands in the archi-
pelago. We spent approximately one week on both Cayo
Pequeno and Cayo Grande, the only islands of the archipelago
where ctenosaurs are found. Although both islands are techni-
cally protected under Honduran law, Cayo Pequeno has
increased protection due to the presence of a research station,
founded by the HCRF. This allows C. melanosterna to thrive,
because both hunting and habitat destruction have stopped. We
caught eleven individuals from this island. Cayo Pequeno is
extremely small and has no obvious physical barriers, so I con-
sider animals from the entire island as one population. Work on
Cayo Grande proved to be much more difficult. Lizards were
very skittish and the island itself is much larger. We nevertheless
caught nine animals, all from one area. Based on the lizards’

Ctenosaura oedirhina from along the Mangrove Canal on Roatan.



behavior and the absence of large individuals, we concluded that
C. melanosterna probably is being hunted regularly on Cayo
Grande by the Garifuna people living on this island. Locals who
helped us came equipped with dogs and slingshots, tools typical
of mainland iguana hunters. Mainland Hondurans also may
hunt on the island and return to the mainland to sell their catch,
as the C. melanosterna on the island are much easier to catch
than C. similis on the mainland.

Isla de Roatan (June)
We caught 25 C. oedirhina at six sites that were spread fairly
evenly throughout the island. Five individuals were caught from
the West Bay area. This area is the site of ongoing development,
where clearing in the past has opened up a rocky area in which
ctenosaurs seem to thrive. We saw no physical evidence of hunt-
ing in this area, although a local, intrigued by our efforts to dig
ctenosaurs out of the rocks, quickly jumped in and caught one
for us. Additionally, we saw very few adults, which could be
indicative of hunting. We caught six individuals at the Paya Bay
Resort on the northeastern half of the island. Interestingly,
ctenosaurs are abundant on the open rock faces abutting the
ocean, and locals have told us that they often see them in the
ocean, although I was unable to confirm this with my own
observations. Four individuals came from Arch’s Iguana Farm.
Although this “farm” is dedicated to the preservation of Green
Iguanas (Iguana iguana), a few C. oedirhina can be found in the
area. Through the efforts of one of the farms caretakers,
ctenosaur breeding may be incorporated into the farm’s objec-
tives. This would be of great benefit to the species, and consid-
erations should be given to helping him with such an effort.

We hired a dory to take us through the Red Mangrove
Canal. This is a tourist route, and was recommended as a place
to find ctenosaurs. We were able to catch four individuals from
this area in about one hour. Hunting pressure appears to be low,
at least in part because the ctenosaurs are a tourist attraction. We
took a second dory trip to the far eastern end of the island and
to the two small islands of Morat and Barbareta. Barbareta is a
private island that is heavily guarded against local poachers of
Green Iguanas, ctenosaurs, and sea turtles. The owner of the
resort on this island seems to be very concerned with protecting
the wildlife. With the assistance of two guards, he allowed us to
collect samples from five individuals. Our trip to Morat was
unsuccessful. We examined the entire southern side of the island,
but saw no signs of any kind of iguana. We saw no tail drags,
evidence of nesting or hatching, or fecal matter. We also saw no
clear signs of hunting, although branches had been cut off the
mangrove trees, the pattern was not typical of ctenosaur hunt-
ing. Santa Elena, located on the far eastern side of Roatan, also
proved unsuccessful, although we did see one individual. We
stopped farther west at Rocky Point and saw many ctenosaurs,
but were unable to catch any as they were extremely skittish.
Hunting pressure on the far eastern side of the island appears to
be high.

The situation for C. oedirhina on Roatan seems to be fairly
good, although the fact that hunting is occurring was no secret.
The island seems to be big enough and contain enough pro-
tected areas to conserve this species. Ctenosaura oedirhina also
seems to be able to exploit many different environments, from

Red Mangrove stands to dry scrub forest, indicative of its eco-
logical versatility, a characteristic that should help this species as
habitats change or are destroyed. I propose that conservation
efforts focus on the populations on Barbareta and at Arch’s
Iguana Farm.

Isla de Utila (March–May)
On Utila, I continued and expanded work initiated in 2005,
which included mark-recapture, collection of DNA samples,
and ongoing evaluations of the status of C. bakeri and C. similis,
with particular efforts aimed at assessing the possibility of
hybridization between the two species. In addition to sites vis-
ited last year, I discovered many new sites, some of which sup-
port only C. bakeri or C. similis, whereas others have both
species. In all, I identified 26 sub-sites located throughout the
island. These sub-sites can be grouped into three main geo-
graphic regions based on both anthropomorphic and natural
barriers and useable habitat connections.

Geographic region one (GR1) encompasses the most east-
erly portion of the island and is divided from geographic region
two (GR2), which encompasses the middle section of the island,
by the presence of Utila Town in the south and uninhabitable
savannah through the interior of the western part of the island.
These barriers may be more of a problem for C. bakeri than for
C. similis. GR1 includes five sub-sites, of which one is occupied
solely by C. similis, one solely by C. bakeri, and three have both
species. We captured a total of 71 C. bakeri (30 males, 32
females, 9 juveniles) and 31 C. similis (five males, 15 females, 11
juveniles) in GR1.

268 IGUANA  •  VOLUME 13, NUMBER 4  •  DECEMBER 2006 PASACHNIK

Typical locally made noose found near the Tradewinds properties.



IGUANA  •  VOLUME 13, NUMBER 4  •  DECEMBER 2006 269CTENOSAURS OF HONDURAS

Geographic region two encompasses the middle section of
the island on both the eastern and western sides of the canal and
is separated from geographic region three (GR3) by the presence
of uninhabitable savannah running essentially north-to-south
through the western section of the island. Although a man-made
canal runs north-to-south through the middle of GR2, it is not
a geographic barrier for ctenosaurs, because it is extremely shal-
low in many areas and trees occasionally form a contiguous
canopy over the water. This barrier, however, may affect C. sim-
ilis more than C. bakeri. GR2 includes 17 sub-sites, two occu-
pied solely by C. similis, 12 solely by C. bakeri, and three sup-
port both species. We captured a total of 271 C. bakeri (118
males, 114 females, 39 juveniles) and 20 C. similis (six males,
nine females, five juveniles) in GR2.

Geographic region three is the largest region and encom-
passes the most westerly portion of the island. GR3 includes
eight sub-sites, five occupied solely by C. bakeri and three
include both species. We captured a total of 40 C. bakeri (14
males, 15 females, 11 juveniles) and five C. similis (1 female, 4
juveniles) in GR3. We spent substantially less time collecting in
GR3 due to the difficulty of reaching the area.

I can now conclude that C. bakeri can be found in nearly
all areas of the island, with the sole exception of the savannah.
Although traditionally thought to be a mangrove specialist, C.

bakeri may actually be more of a generalist. Although they thrive
in mangroves, I also found them doing well in dry areas that
were once thought to be occupied solely by C. similis or to be
entirely ctenosaur-free. This may be an artifact attributable to
habitat destruction, but occupied areas on the northwestern side
of the island, which are virtually free of people, argue otherwise.
Additional observations from the eastern shore indicate that C.
bakeri often exploits dry beaches far from mangroves stands,
even during periods other than the breeding and nesting seasons.
Similar to C. oedirhina on Roatan, I suggest that C. bakeri can
be considered a habitat generalist that is adept at exploiting man-
grove swamps. However, on Utila, C. bakeri shares the island
with a congener (C. similis) that appears incapable of surviving
in the mangroves.

I also visited many of the small cays off the southwestern
and western coasts of Utila, and found no evidence of iguanas.
My purpose on these cays was to check for the presence of
ctenosaurs and evaluate them for the possible introduction of C.
bakeri rescue populations. The only cay that might be able to
support iguanas is Bird Cay, which offers suitable habitat and is
free of human visitation. However, the island is very small and
could support only a small population of lizards.

I was unable to recapture enough individuals to estimate
accurately population or subpopulation sizes. This may reflect

Ctenosaura bakeri from northwestern Utila.



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Ctenosaura similis from a new development on the eastern side of Utila.

Cleared area on the eastern side of Utila at the Blue Bayou lagoon.



IGUANA  •  VOLUME 13, NUMBER 4  •  DECEMBER 2006 271CTENOSAURS OF HONDURAS

the fact that only 100 individuals were marked in 2005 or it
may be attributable to the recent increase in iguana hunting on
the island. Although questions regarding hybridization between
the two species will be addressed more conclusively once molec-
ular evidence can be taken into account, I found no obvious
morphological evidence suggesting that hybridization occurs
more than very rarely, supporting tentative conclusions based on
molecular work in 2005.

Although populations of C. similis and C. bakeri on Utila
seem stable at this time, hunting, development, and traffic on the
island have increased dramatically in just the past year. In 2005,
I rarely saw hunters or signs of hunting. In sharp contrast, I rarely
had a day in the field this year during which I did not encounter
hunters, find evidence that people had been hunting, or hear
people hunting with guns. Additionally, habitat destruction con-
tinues to threaten the wildlife of Utila, particularly the illegal
destruction of mangrove forests. Utila’s roads and associated traf-
fic also are expanding. This year, for the first time, I found road-
killed ctenosaurs. I strongly recommend support of the habitat
action plan being developed by the Utila Iguana Research and
Breeding Station to buy land, give land owners incentive to be
ecologically friendly, and hire guards to protect wildlife.

Summary
Honduran ctenosaurs face many threats. In the south, the great-
est threat is illegal poaching. In the north and on the islands, in
addition to illegal hunting, the greatest threats are habitat
destruction and a growing human population. Throughout the
country, the sporadic or total lack of law enforcement that
should have been protecting these animals since 1994 leaves

them vulnerable. In 2004, the IUCN listed all of these
ctenosaurs, except C. similis, as “critically endangered,” indicat-
ing the severity of the situation. Without local protection, their
future is questionable at best. Only those individuals and insti-
tutions that feel a moral obligation to protect the diversity of
nature can postpone the seemingly inevitable extirpation of at
least many populations.

Acknowledgements
The success of this field season would have been impossible
without the help of many amazing volunteers: Dennis
Baulechner, Corey Shaffer, Jeff Liechty, Wendy Naira, Melissa
Issis Medina, Sammy Nuñez, and Hadas Grushka, my thought-
ful mentors Drs. Arthur Echternacht, John Iverson, and Tom
Near, The Utila Iguana Research and Breeding Station, The
Overseas Research Station on Roatan and Dr. David Evans, The
Cayos Cochinos Foundation, Dr. Gustravo Cruz, Jorge Ferrari,
and the many offices of AFE-COHDEFOR. Additional thanks
go to Oscar Maccio, Colin Meeks, and Martin Nuñez for aid in
translating the report on which this article is based.

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Myers, N., R.A. Mittermeier, C.G. Mittermeier, G.A.B. da Fonseca, and J.
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Dead Ctenosaura similis hit by a four-wheeler on the road near Annie Marelli’s Hotel.




