The Green Iguana

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The Green Iguana
(Iguana iguana)
Can domestication save this species?
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Seemingly common, the green iguana is the second
most heavily traded vertebrate in world commerce
In 2009, over 2,000,000 were imported into the
U.S. alone, mostly for the pet trade
Found from Mexico, throughout Central
America, and into South America
In actuality, green iguanas are rapidly becoming
endangered. Many local populations
extirpated, particularly in Central America
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Life History
Can grow to 5 in captivity, typically smaller in
wild - arboreal and herbivorous - eat
leaves, fruit, and flowers
females typically nest every year, lay up to 60
eggs per clutch - often nest in communal
burrows, to which they return every nesting
season
young hatch at the beginning of the rainy
season, coincident with years flush of new leaf
growth
natural enemies include birds, carnivorous
lizards, crocodiles
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What are the problems for green iguanas?
Deforestation - arboreal herbivores need forests
- cutting reduces available habitat
1)
Overexploitation by humans
2)
for the pet trade - eggs and adults taken from
the wild to be sold as pets
a.
for food - iguana meat is highly prized, eggs
are a delicacy
b.
because they often nest in groups, it is easy for
a poacher to devastate a local population -
unregulated take is a problem
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What is being done for green iguanas?
Scientists at the Smithsonian Tropical Research
Institute instituted captive breeding programs
in 1984 to supplement wild populations
initially collected 700 eggs - virtually all
hatched
survival of hatchlings very high in captivity vs.
90 mortality rate in wild hatchlings
iguanas born in captivity are easily bred, unlike
wild- captured adults
captive breeding of iguanas very successful
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What is being done for green iguanas?
Scientists now promoting the creation of iguana
farms
if local farmers could be persuaded to raise
iguanas, the species, the farmers, and the
forest would all benefit
iguanas benefit - farms take pressure off
wild populations
forests benefit - iguanas live and feed in
tropical rainforest, raising them will prevent
the clearing of forests for pastureland
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Iguana farming
farmers benefit - iguana farming is cost-effective
ectotherms - thus they have lower metabolic costs
than cows - more energy goes into body mass - 10x
more body mass yield per area with iguanas than
with cows
iguanas require less food than cows, can feed in
trees, thus take up less space
as many as 60 iguanas can cohabit a 12 sq.
yard enclosure
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Conclusion
The domestication of the green iguana may save
the species from extinction
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Thought Question
Do you think it is good that we may be adding yet
another species to the list of animals and plants
that human beings have taken under our control?