1. Comparison of the Dry Forest of
Guanica and the National Forest
of the Caribbean “El Yunque”
Group #1: Carla J. Figueroa Zuleika Velázquez Crystal K. Colón
Luis F. Centeno Gustavo Martínez John E. Muñoz

2. Introduction
 On the days of June 19 and 21, we had two separate
field trips to two completely different areas of
Puerto Rico. We traveled to the Dry Forest of
Guanica on June 19, then to the National Forest of
the Caribbean “El Yunque” on June 21. After having
travelled to both forests, we were able to compare
these completely different, yet similar areas.

3. Climate and Location
Comparison

4. Dry Forest of Guanica
 Located in the southwestern area of Puerto Rico, this
forest expands all the way from Guánica to Ponce,
covering roughly over 11,000 acres of land.
 The climate is hot and dry, due to a lack of precipitation
because of the restrictions placed by the Cordillera
Central de P.R., which does not allow the passage of
rain-carrying winds.
 The forest receives approximately 30-40 in. of rain per
year.
 Because of the harsh climate and extreme temperature,
the organisms have adapted to thrive and survive in this
forest.

5. The National Forest of the
Caribbean “El Yunque”
 Located 49 Kms north-east from San Juan in the Sierra of
Luquillo, with an average temperature of 78 Fahrenheit
at the lowest altitudes and around 65 degrees Fahrenheit
in areas surpassing the 3,530 feet.
 With an average precipitation of 250 inches per year.
This means that there are very sudden yet powerful
downpours daily causing the soil of the forest to suffer
significant loses due to the erosion.
 Due to the great quantity of precipitation the island of
Puerto Rico depends on the forest to acquire enough
water to supply to the inhabitants.

6. Flora Comparison

7. Flora
 The flora of the Dry Forest of Guánica is no bigger than 49 ft.
because in that form they conserve water and do not spend it
in the production of biomass; where as in El Yunque
rainforest the vegetation can reach an altitude of as high as
125 ft. because they have more access to water and can
produce more biomass.
 In the Dry Forest of Guánica, the flora modified their
activities for the principal goal of all, to conserve water. Some
of the adaptations are: vertical orientation to reduce exposure
to the direct sunlight, stems that carry out photosynthesis and
plants with spines. One of the adaptations that the vegetation
in El Yunque made is the adventitious roots to have more
support and reducing the occurrence of landslides.

8. Flora
 El Yunque possesses more vegetation diversity by area unit
than the Guánica Dry Forest. The number of endemic species
of trees are 23 and 19 in each forest respectively.
 The rainforest floor is loosely packed because of the high
precipitation. Meanwhile, the dry forest has tightly packed
soil due to its low precipitation.
 Most of the vegetation in both forests have adaptations to
subsist in their environment like semi-deciduous in the
Dry Forest of Guánica which lose their leaves during the
summer and in El Yunque they conserve them all year and
they lose their water.

9. Flora
 The roots of the rainforest flora are superficial roots;
whereas the roots of the dry forest are deeply
planted in some areas but superficial in others.

10. Principal Canopy of El Yunque
Principal Canopy of the Guanica Dry Forest

11. Adventitious roots
Corcho Tree
- This tree represent
how the vegetation
placed their leaves in
vertically form

12. Yagrumo Macho
Didymopanax
morototoní

El Yunque
- Endemic of Puerto Rico
Piteselobiun
- Endemic tree of
Guanica Dry Forest

13. Fauna Comparison

14. Fauna
Dry Forest of Guanica The Caribbean National Forest
 There have been a very Approximately 100 vertebrates
valuable herpetofauna which including amphibians and birds
includes 21 species of reptiles, 6 live in the different forests of “El
species of amphibians and 136 Yunque”.
species of birds.
• Compared with the Rainforest the Dry Forest has 31 versus 20 species of
birds per 1,000 individuals.
• The amphibans’ function in the Rainforest is mirrored by insectivorous
birds in the Dry Forest.
• The Dry Forest contains a wider range of insect species than the
Rainforest.

15. Fauna
 Both forests have in common species like the San
Pedrito (Todus mexicanus) and the Pajaro Bobo
Mayor (Saurothera vieillotil).
 There are endangered species in both forests. The
most notable are the “Sapo Concho” in the Dry
Forest and the “Coqui” and the Puerto Rican Parrot
in the Rainforest.

16. Fauna
Different
species of Puerto Rican
snails Parrot

Coqui
Puerto Rican Boa

17. Birds
San Pedrito
Reinita Mariposera
Pajaro Bobo Mayor
 Jui de Puerto
Rico
Guabairo 

18. Enviromental problems
that affect the Dry Forest
and the Rainforest

19. Contamination
 In the Rainforest of el Yunque there is a large
amount of tourism. This increase in tourism brings a
large quantity of sound and waste contamination.
The sound contamination is contributed by the large
amount of cars and loud groups of people that go
up the mountains to visit the forest. And it is these
very people that contribute to the amount of waste
that increases in the forest. They also throw their
trash onto the floor of the forest without considering
the effect on the environment, or no consideration
for future visitors.

20. Construction
 The construction is a factor that has affected all
major forests. In the passing of the years the
population has risen, therefore the population has
extended into areas were it is forbidden. An
example: until recently in the Dry forest there were
homes and businesses that occupied great quantities
of it. Due to the protection of the forest, the homes
and businesses were removed and the forest
reestablished itself to its natural state in these areas.
In the National Rainforest of the Caribbean (El
Yunque) there are still homes or establishments that
occupy the lower east side.

21. Global Warming
 Due to the natural disasters that have occurred in
the resent years the axis of the Earth has tilted one
degree causing for drastic changes in the
environment. Due to the change places that are
usually dry during summer may have precipitations
and winters that are normally warm can feel cold.

22. Tourism
 Just as much as The Yunque and The Guanica Dry
forest receive a lot of visiters from all around the
world, which is good to the economy of the island.
But in the other hand, tourism brings with itself
ignorance and disrespectful attitudes like leaving
the trash, taking plants from its natural
environment , cars that disperse gases and at the
same time the amount of contaminants that destroy
both forests. It would be ideal for both Puerto
Ricans as to tourists that they respect these forests
and give an effort to keep them clean.

23. Deforestation
 One of the biggest problems that these two (2)
forests face is deforestation. This problem affects the
extension of the land, minimizing the growth.
Along with the problems that affect these forests,
like changes in habitats and the negative effect in
the fauna just like the ones that affect the Puerto
Rican parrot, can bring the deterioration of the
forest.

24. Factories
 The factories that make use of large quantities of
land causing deforestation, the utility of large
amounts of resources (big quantitites of water), they
take the infrastructure to the plants or in some cases
factories can lead to the removal of trees and land to
place the pipes, and they also cause sound, light,
soil and water pollution in the environment.

25. Conclusion
 The ecosystem of Puerto Rico is very diverse. This
111 by 39.5 mile island includes a tropical rainforest
(National Rainforest of the Caribbean) in the north-
east, to the dry forest of Guánica at the south of the
island. These to completely different ecosystems
have very similar characteristics. After a long
analysis of the communities found in these forests
we have come to the conclusion that Puerto Rico is a
greatly varied island with a haven for diverse
research.

26. References
 Bosque seco de guánica. (n.d.). Retrieved from
http://ponce.inter.edu/acad/cursos/ciencia/pages
/guanica.htm
 Ramírez, J. T. (n.d.). El bosque nacional del caribe el
yunque: Fauna. Retrieved from
http://cremc.ponce.inter.edu/yunque/fauna.htm
 (n.d.). Bosque nacional del caribe (el yunque).
 Ricart, C. M. (n.d.). El bosque seco subtropical.