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OCR for page 355
34
Black Iguana
The work on green iguana husbandry may apply It
also to the black iguanas (Ctenosaura similis, C. ~
acanthura, C. hemilopha, and C. pectinata). These en
are similar lizards that live in dry habitats throughout
Central America.
Exploitation of wild black iguanas for food began in ~ ~
ancient times and has continued in most places over hundreds of years
without much harm to the natural populations. Until the 1970s, Latin
Americans could obtain the meat and eggs with little effort, and the
animals sold cheaply in city markets. In recent years, however, the
lizards have become scarce and prices have risen sharply. For instance,
in 1976 the central market of San Salvador was selling large specimens
for the equivalent of 80 cents, but by 1979 prices were generally from
three to six times as much. Today, black iguana meat costs more than
fish, poultry, pork, or beef.
Eating small game animals is deeply rooted in the traditions of
Central America and cannot readily be changed by legislation or
education. Despite official edicts, campesinos on a subsistence diet
will not willingly forego the little meat they get by capturing and eating
lizards. Moreover, legislation is seldom effective because there are
too few enforcement officials.
As with the green iguana, it seems likely that when the factors
causing hatchling mortality are reduced, a large harvestable annual
surplus can be produced. Black iguanas efficiently convert vegetation
into high-grade protein suitable for human consumption. Young ones,
however, are insectivorous and carnivorous rather than purely herbiv-
orous, and during their first weeks of life may require a more expensive
diet (perhaps meat scraps) than green iguanas require. Moreover, most
insectivorous lizards require moving prey. They may or may not accept
meat scraps as food.
' We use the name black iguana. In Mexico, it is called merely iguana; in English, it is
commonly called spiny-tailed iguana. In Central America, it is called "garrobo" and
"galling de palo" (chicken of the trees).
355
OCR for page 356
356
APPEARANCE AND SIZE
MICROLIVESTOCK
Black iguanas are smaller and more stocky than green iguanas, but
weigh up to 3 kg. Their tails are spiny and short. The scales on the
tail are enlarged, grow in spirals, and are sharp-pointed. Other than
that (apart from being generally grayish black in color), the two animals
. . .
are slml ar in appearance.
DISTRIBUTION
The different black iguana species range from northern Mexico along
both coasts of Central America to Panama and Colombia's Caribbean
islands. Most tolerate moderate human presence well, often thriving
around town garbage dumps and cemeteries.
STATUS
As recently as 1981, black iguanas were shipped to markets by the
truckload. Today, they are generally limited or even absent over much
of their original range. Nevertheless, they are still the major game
animals across extensive areas of Central America. Many of those
taken are gravid females, which is disastrous for the populations.
Excessive insecticide spraying is also thought to be reducing their
populations in some areas.
HABITAT AND ENVIRONMENT
Black iguanas thrive in dry, open woodland. They particularly like
rocky hillsides, for they depend for shelter on crevices, rock piles, or
soft soil in which they dig burrows.
BIOLOGY
These omnivores feed on foliage, flowers, and fruits, but also on
insects and small vertebrates. Adults spend some of their time climbing
trees, but they are much less arboreal than green iguanas. Hatchlings
are initially terrestrial but have a mostly arboreal stage in their early
weeks of life.
Females lay one clutch of 2~90 eggs each year. The eggs are much
smaller than those of the green iguana and therefore are not as popular
a food.
OCR for page 357
BLACK IGUANA
Distribution of the black iguana.
BEHAVIOR
357
Or
-
~_
These lizards live in burrows or in holes in trees. A typical burrow
has several entrances and is 1-2 m long. Several females may combine
efforts to form a complex communal burrow with several individual
nest chambers. They are such diligent diggers that many are caught
while absorbed in the task of adding a new room.
USES
In some places, even where they are not common, black iguanas
are still intensively hunted. Because their meat is valuable, the reward
justifies the considerable effort involved in finding and killing them.
Hence, where populations are so depleted that organized hunting is
unprofitable, the animals are still subjected to relentless destruction
by individuals.
HUSBANDRY
Farming black iguanas is a novel idea. However, it is not a foolish
one. In 1981 the Centro de Recursos Naturales (CENREN) in El
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358
MICROLIVESTOCK
OTHER IGUAlYAS
Other iguanas that deserve consideration for husbandry
include the rock (rhinoceros) iguana (Cydura comets), a
herbivorous lizard of the Antillean region. This has been raised
in considerable numbers at the National Zoo of Santo Domingo,
Dominican Republic. Captive-bred specimens have reproduced
at the age of 32 months, average clutch size has been about
15, and the average incubation time has been 82 days (at
31°C). The innate tameness of these island iguanas renders
them better adapted for captive rearing than either the green
or the black iguana, and their greater size is an advantage as
well. On the other hand, the length of time required to reach
maturity, and the relatively small egg clutch (about half that
of the green iguana and one-third that of the black iguana) are
definite disadvantages.
A related species, Iguana del~cat~ssima, also deserves re-
search and conservation attention. It occurs in the Leeward
Islands and Martinique, and (as its specific name implies) is
even better eating than the green iguana.
* Infonnation from A. Ferreira.
* * Lazal, 1973.
Salvador started a black iguana farming project. Since then, its
researchers have collected data on growth rates, feeding patterns, and
the maintenance and reproduction of captive adults. The program
offers some promise of maintaining breeding stock in large outdoor
enclosures, of producing large numbers of hatchlings, and of restocking
depleted areas.
ADVANTAGES
Latins believe that various ailments are cured or benefited by the
flesh of these lizards, so they willingly pay much more for their meat
than they would for equivalent amounts of other meats. In most places
where the two occur together, the black iguana is preferred over the
green Iguana.
Compared with green iguana, the black iguana reproduces readily
in captivity and has an even higher reproductive potential (averaging
43 eggs per clutch). It has the additional advantage that it thrives in
deforested and altered habitats. It can survive near human settlements
OCR for page 359
BLACK IGUANA
359
despite the attacks of dogs and cats, and it attains dense populations
in suburban lots or open spaces. (It survives even downtown in cities
such as Managua, but not in dense populations because dogs, cats,
and humans take so many.) Hence, even in towns and cities, there
are habitats capable of supporting it.
Black iguanas will feed on weedy vegetation or garbage, and adults
seem easier to maintain in captivity than their green iguana counter-
parts.
LIMITATIONS
The long delay (probably at least two years) before the animals
reach marketable size might make it difficult for the grower to compete
with common meats such as poultry or fish.
Certain parasitic worms can make the flesh inedible.
Although smaller than green iguanas, black iguanas are much more
aggressive and will defend what they perceive to be their territory.
They can inflict a painful bite. They also tend to escape from captivity
more readily.
As noted, these omnivores depend on animal matter during part of
their life cycle.
RESEARCH AND CONSERVATION NEEDS
The biology of the black iguana deserves much more study.
Management techniques developed for the green iguana should be
tested for their applicability for black iguana species. Harvesting and
recruitment schemes must be developed to create sustainable popu-
lations in the wild. The specific needs for feeding the young also need
to be addressed.
OCR for page 360
I am convinced that in the Third World, it is only when poor people
are assured of their livelihood that they will help us to safeguard their
natural environments. So long as people remain hungry, it is very
difficult to talk to them about conservation. As a result, I believe that
development and conservation are inseparable. Only when conservation
takes on a dimension of helping the poor, the downtrodden, the
destitute, will it have an enduring impact.
M.S. Swaminathan
International Union for
Conservation of Nature and Natural Resources
I suspect that wildness is an inherited characteristic as was found for
the turkey by Starker Leopold. So in attempting domestication one
should expect to have difficulty until there are enough animals that
you can select breeding stock for quietness and tractability.
Ian McTaggart Cowan
Emeritus Professor of Zoology
University of British Columbia
Cattle will never be extinct for the simple reason that man eats cattle.
The best way to preserve wild species is by demonstrating that they,
too, can be a valuable resource.
Ernie Matteram
New York Times Magazine
Wildlife utilization should be considered a legitimate form of land use,
just as much as livestock husbandry. In fact, what has happened in
the past is that Man has domesticated a limited number of animals,
mainly in the temperate zones, while overlooking a considerable
potential of other animals, which could be domesticated or used with
equal validity.
Antoon De Vos
Representative terms from entire chapter:
black iguanas
