How to prevent?

                     
All of this damages would prevented if humans stop selfishness, just thinking about what you like and seek only their own advantage and think of those creatures who have no voice to communicate with us and ask for their home. The extinction of a species is also caused by the direct result of human activities. Of these factors, the most affecting wildlife is the destruction or modification of habitat.

                                                 

• Destruction or alteration of habitats 
• Destruction of lagoons and mangroves.  
• Destruction of rocky areas. 
• Destruction of lowland forests.
• Limited natural habitat.
• Development and urban growth.
• Disturbance of the islands off the coast.
• Drainage and flood landfill.
• Environmental Pollution (Water, Air and Land)
• Over exploitation

• Collection (over fished)
• Commercial purposes (trade secret)
• Over hunting
• Introduction of exotic - The introduction of exotic animals affect our ecology. 
• Mongooses, goats, rats, pigs

Telenoticias (2012, 5 December). More Protection for Endangered Species in Puerto Rico. Retrieved From 

http://www.telemundopr.com/telenoticias/ciencia/Mas-proteccion-para-las-especies-en-peligro-de-extincion-en-Puerto-Rico-182158291.html
 Our Resident Commissioner was interesting in protect coral reefs are endangered. This will help protect coastlines from storms and erosion. Also banned the species's import like construction's snake.

Lopez, L.(2011, 6 April) Endangered Species in Puerto Rico.[PowerPoint Slide] Retrieved From

http://www.slideshare.net/lilibet8579/animales-en-peligro-de-extincin-en-puerto-rico 
 In Puerto Rico are 39 animals of endangered species protected by law number 241 (Wildlife Act). Nosmuestra the endangered species and the reasons why they are in this terrible situation.

References:

• Departamental of Natural and Environmental Resources. (2009).Endangered Species in Puerto Rico. Retrieved from http://www.mitaino.com/ambiente/animales_extincion