The document discusses the overpopulation of green iguanas in Puerto Rico. Green iguanas were originally introduced as exotic pets, but many were released and have no natural predators in Puerto Rico. They are damaging local ecosystems like mangroves. The author proposes a controlled sterilization program to help reduce the iguana population. The program would involve capturing 50 iguanas, identifying them, surgically sterilizing 25 males and 25 females, observing their behavior, and releasing them to determine if sterilization prevents reproduction. This would help curb population growth without fully extinguishing the species.

1. Overpopulation of iguanas in Puerto Rico 1
Overpopulation of Iguanas in Puerto Rico
Antonio Romero Ramos
RISE Program
Bio 3031
July 6, 2009

2. Overpopulation of iguanas in Puerto Rico 2
After a time when the population of iguana in Puerto Rico was high, nowadays it’s still been a
problem. Iguanas are causing damage to many ecosystems like mangroves. The purpose of this
work is to aware people about this problem and finds a way to resolve it. Establish a sterilization
program I’ll be contributing to the biological control of iguanas and protecting the ecosystems.
The question is how can we control the population of iguanas? My objective is to create a
biological control of this population because they aren’t causing a fast damage but if we don’t
control it now, it’ll turn in a bigger problem. The kind of iguana that is causing the
overpopulation is known as the green iguana. It’s native from the tropical jungle of Central
America and South America. The green iguana (Iguana iguana ) is from the kingdom Animalia
and it’s a reptile. Being a reptile they have skin with scales. They grew from 7.5cm to a size of
2m including the tail that can be the half of their body. They have green skin but it varies because
it could have black stripes, grayish color, etc. The green skin helps them to camouflage from the
predators. A crest bigger in male iguanas. Their legs are short, have claws to climb. They are
diurnal, during they hide in trees. They are cold-blooded; they can’t control their temperature so
that’s why they like the Ultra Violet rays, besides it helps in their metabolism.
They Nutrition is based on plants so they are herbivores. As cows in their stomach they have
microorganisms (prokaryotes) that help them to digest cellulose. They eat leaves, fruit, and
flowers of selected herbs, shrubs, trees and vines. They reproduction is bases on eggs. They are
polygamous it means that they do not reproduce with a specific organisms of the kind, as the

3. Overpopulation of iguanas in Puerto Rico 3
most of birds do. The infatuation between them occurs when the male iguana shakes his head to
catch the attention of the female. The infatuation basically occurs during November and
December. The interaction occurs from February to April. Female iguanas put approximately
30-60 eggs, it depends on the size.
The possible answer of how did they get here? Is that people kept these animals as a pet, but
when they cannot afford the responsibility they release the iguanas anywhere. The problem is
that in Puerto Rico they do not have a natural predator. In their native place they have natural
predators such as anacondas, felines, foxes. That’s why we are having an overpopulation of
iguanas in Puerto Rico.
My hypothesis is that if I create a Controlled Sterilization Program it’ll control the population of
iguanas. This Controlled Sterilization program as its name says is control, which means that I
won’t sterilize every iguana because I just want to control not to extinguish them.
The process that I’ll follow to make my investigation is:
First, I’ll get the permission from the Department of Natural Resources to use the iguanas. I
know that when I use animals I can’t provoke any pain to them. If the animal has to be sacrifice I
need to know how and what I’m going to do with it. I’ll going to talk with the biologist in Isla
Magueyes to see if the can provide me the iguanas. Once I have the iguanas and the

4. Overpopulation of iguanas in Puerto Rico 4
authorization, I’ll contact a veterinarian and explain my investigation. Also that the method of
sterilization that I want to use is the castration (removes the testicles of males and eggs on
female). The next step is recluse 50 iguanas (25 of each sex). Identify them with a chip to control
their location. So make sure that they do not escape from the place that I’ll choose. The place
will be in their habitat but it will be restrained. I’ll observe their reproductive behavior. The
iguanas will be submitted to the surgery. When the wound has completely close then I release
them to the restrained area. I’ll observe their reproductive behavior after the surgery and compare
if it’s equal to before the surgery. I’ll wait until their season of reproduction if the times when I
do the investigation do not concord with it. Weekly I’ll go and see if the sterilization was
effective, if it was, and how many it was.
.

5. Overpopulation of iguanas in Puerto Rico 5
References
Campbell, Reece. Biology. Eight Edition. Pearson Benjamin Cunnings. Chapter 5. Page
Unknown Author, Green Iguana. http://www.thewildones.org/Animals/iguana.html
Unknown Author, Características de la iguana verde.
http://trabajo.commx/caracteristicas_de_la_iguana_verde.html
Wissman, Margaret A. Iguana Nutrition. 2006. http://www.exoticpetvet.net/reptile/nutrition.html