Definition
Search

  Búsqueda alfabética
 
Search by Word

Search by Topic

Glossary of Terms >



Invasive species

Throughout the ages, many species of microorganisms, plants and animals have been introduced or transported by humans to places where they did not previously reproduce naturally. Once they spread and occupied new habitats, many of these new species became aggressive and became pests and pathogens. This proved harmful to the environment, both for endemic species and for human populations in these areas. At present, the invasion of exotic species in previously unoccupied areas is one of the greatest threats to natural life on our planet. Never before throughout human history, has there been a biological invasion of such magnitude. For this reason, prevention and control of invasive species is one of the great environmental challenges of our times.

Scientific studies have identified three types of routes invasive species follow to reach their new habitats: 1) by means of transportation (trains, ships, etc.), packaging, equipment and non-living products (such as clay tiles); 2) through living products not intended for release into the natural environment (for example, fruits, vegetables, pets or zoo animals); and 3) through live products that are intended for release into the natural environment (crops, wild game or fish for aquaculture.) Experts agree that there are three key factors to the success that an invasive species has in spreading aggressively: 1) the abundance of resources, such as space to grow, intensity of light (energy), presence of nourishment, etc.; 2) the absence of its natural enemies; and 3) the similarities between the conditions in the new habitat and in its original area of natural distribution (climate, soil, etc.) All these factors influence the success of the species when it invades a new geographic area, expands the scope of its proliferation, and disrupts the lives of the species that naturally inhabit it.

The cost of invasive species
Alien Species in the Dominican Republic
Main strategies for managing invasive species
International Conventions
Projects in Dominican Republic

The cost of invasive species

Recent studies emphasize the fact that invasive alien species threaten livelihood and economic stability in every continent. An analysis conducted a few years ago estimated the damage caused by invasive species worldwide to be more than US$1.4 billion, which is equivalent to 5% of the global economy. It is widely known that invasive species such as rats are responsible for large losses of basic grain crops in many parts of the world. At the same time, invasive species are one of the major threats to species diversity. It is estimated that since the start of the age of great explorations by Europeans during the XV and XVI centuries, at least one third of all species extinctions in the world are the result of biological invasions by aggressive alien species.

Because of their proximity to North, Central and South America, the Caribbean islands have served as a gateway to the Americas for European ships ever since the arrival of Christopher Columbus in the late XV century. This has caused the Caribbean islands to become a testing ground for the introduction of exotic species, which, accidentally or incidentally, entered the islands of the West Indies. Some species were deliberately introduced for forestry or mixed farming production (for example, for high performance grazing), while others arrived unintentionally, as was the case of the European rats. Thus, traffic of cargo and goods, including plants and animals, to markets in the Americas, resulted in islands, such as The Hispaniola, suffering a devastating biological invasion, which began over 500 years ago.

To assess the magnitude of the environmental problem caused by alien species, it is essential to conduct, at a national level, studies of the invasive species that undermine national resources. In the Americas, countries such as Brazil, Mexico and the Dominican Republic, have recently initiated national surveys that provide a first outline of the problems posed by many invasive species that affect the condition of the environment. Brazil, for example, has reported the presence of more than 200 exotic species of animals and plants spreading aggressively across the country, causing heavy biological and economic losses.

Back to Top

Alien Species in the Dominican Republic

In the case of the Dominican Republic, the presence of at least 186 invasive alien species has been reported. It is estimated that most of them are also present in the Republic of Haiti, the country with which the Dominican Republic shares the West Indies island of The Hispaniola. Other Caribbean countries report similar numbers of invasive species: Puerto Rico is home to at least 182, while the Bahamas report some 159, and Jamaica a total of 102.

The following chart shows some of the most aggressive and harmful invasive species present in the Dominican Republic.

Common Name

 Scientific Name

Classification

Black Sigatoka

(Mycophaerella fijiensis)

Fungus

Tobacco blue mold

(Peronospora tabacina)

Fungus

Citrus black fly

(Aleurocanthus woglumi)

Invertebrate – Insect

Whitefly

(Bemisia tabaci)

Invertebrate – Insect

Palm seed borer

(Callosobruchus sp.)

Invertebrate – Insect

Laurel thrips

(Gynaicothrips ficorum)

Invertebrate – Insect

Coffee berry borer

(Hypothenemus hampeii)

Invertebrate – Insect

Rice snail

(Ampullaria glauca)

Gastropod mollusk

Pondweed

(Eichornia crassipes)

Aquatic plant

Honeysuckle

(Lonicera japonica)

Climber

Shrimp Fern

(Nephrolepis multiflora)

Fern

Acacia

(Acacia mangium)

Tree

Carp

(Cyprinus carpio)

Vertebrate – Fish

Rainbow trout

(Oncorhynchus mykiss)

Vertebrate – Fish

Tilapia aurea

(Oreochromis aurea)

Vertebrate – Fish

Catfish

(Heterobranchus bidorsalis)

Vertebrate – Fish

Maco toro

(Bufo marinus)

Vertebrate – Amphibian        

House Sparrow

(Passer domesticus)

Bird

Domestic cat

(Felis catus)

Mammal

House mouse

(Mus musculus)

Mammal

Black rat

(Rattus rattus)

Mammal

Back to Top

Main strategies for managing invasive species

As mentioned above, the main strategies for managing the arrival and subsequent destructive impact of invasive species are: pest control; prevention of the invasion of competing species, parasites, predators or habitat disruptors; reduction of illegal activities; and conservation of native biodiversity. In this context, it is essential to teach local communities how to remove invasive species from infested areas. Furthermore, promoting responsible tourism, through a process of raising awareness in tourists visiting vulnerable countries such as the Caribbean islands, is essential when seeking to avoid the potentially dangerous transfer of species between these territories and continental countries. The establishment of reliable information mechanisms which permit informed decision making, as well as any subsequent adjustments that may need to be made to these mechanisms, will be key to successfully implementing the strategies. In this respect, team work that includes the cooperation of all actors -governments and port authorities, NGOs, importers, tourism companies and research centers- is essential and a condition without which it will be impossible to prevent and control invasive species and the extensive damage they are causing to the environment, health and economy of the islands, as is the case of The Hispaniola.

Many experts acknowledge that it is urgent for governments to better control the access routes by which invasive species are transported, such as ballast water, containers and packaging for transport, as well as the commercialization of exotic species and animals. This way the destructive invaders can be prevented from taking possession of the environment and from attacking natural resources and economic welfare. In fact, prevention may help save money in future costs for eradication, human healthcare, and agricultural costs arising from poor crops. Controlling and eliminating invasive species is much more expensive than preventing their arrival.

Back to Top

International Conventions

The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), of which the Dominican Republic is a part since 1987, provides an appropriate framework to work on the prevention and management of invasive species. The objective of this international convention is to ensure that international trade in wild plants and animals will not cause a threat to survival. It proposes, among other things, to implement sanitary and quarantine controls at a national level which ensure that the populations of native species are not affected by the arrival of exotic species or by their passing through the country.

Complementing the CITES convention, the Convention on Biological Diversity (CBD) acknowledged in 1992 the threat of invasive species as a major global priority. Recognizing the immense need for joint efforts to prevent the spread of invasive species throughout the world, the CBD has provided a few additional opportunities for joint actions against biological invasions in an increasingly globalized society. According to the CBD, some of the actions to be taken in the next few years are: 1) expanding the scientific, institutional and legal capabilities that countries need to effectively fight invasive species; 2) establishing guidelines and benchmarks for countries to achieve, at the very least, a minimum level of protection; 3) encouraging and facilitating regional collaboration -as in the Caribbean islands- to confront common threats; and 4) establishing the appropriate mechanisms to fill the gaps in the international legislation relating to the routes by which invasive species move.

Fortunately, several Caribbean countries have already recognized the prevention and control of invasive species as a high priority of national interest. For this reason, countries such as the Bahamas, Jamaica and the Dominican Republic are developing frameworks for capability building and institutional strengthening in this area. In order to take action, these countries are applying the principles set forth in the international conventions mentioned above. For example, in 2002 the Dominican Republic recognized, as a top priority, the need to increase its research capability so that it would be able to quickly detect the arrival of suspicious species to the country. In view of this need, in recent years two major projects were developed locally, with the objective of identifying, preventing and controlling invasive species in the country.

Back to Top

Projects in Dominican Republic

The first project, implemented by the Ministry of Agriculture, seeks to control invasive pests caused by the Pink Hibiscus Mealybug (Maconellicoccus hirsutus) or PHMB. This Mealybug spread throughout the Caribbean in the nineties, causing multimillion-dollar losses. This phenomenon was observed in the Dominican Republic in 2002. The Mealybug attacks dozens of crop species, including beans, citrus, coconut, coffee, cucumber, peanuts, and of course, ornamental flowers such as the Hibiscus.

The second project, known as Project I3N of the Inter-American Biodiversity Information Network (IABIN) is funded by the Global Environment Facility (GEF) of the World Bank, and is managed by the Organization of American States (OAS). Its goal is to catalog the presence of invasive species and facilitate the exchange of information about them among the countries of the Americas. Some benefits of this initiative are the promotion of scientific and technical cooperation, the support of decision making by providing access to key information, the development of innovative tools to share information in an increasingly interconnected world, and the promotion of information management standards.

It is believed that the establishment of a learning network on invasive species in the Caribbean, involving those in charge of agriculture, international trade, conservation, natural resource management and other issues, is vital for the appropriate management of biological invasions. The objective of such a network is to share techniques and resources to fight invasive species that are already in their territories, and to develop strategies to prevent the entry of new species. This way, communication barriers between the islands’ government agencies, NGOs and private entities can be eliminated, in order to be more successful in preventing and controlling access routes to the island countries. The I3N IABIN Project could serve as a basis for creating this network of learning and a starting point in the Caribbean.

In 2002, with funding from the U.S. Agency for International Development (USAID), the Ministry of Environment and Natural Resources of the Dominican Republic developed a strategy for managing invasive species. Within this framework, it proposed the following overview: establish an alien species trade system regulated in accordance with criteria based on research, monitoring, interagency coordination, environmental education, information and community participation, and under the principles of prevention, accountability and national sovereignty, seeking that populations of local native and endemic species not be affected significantly by the presence or transit of alien species. With this national strategy, the Dominican Republic is taking the lead in managing environmental problems caused by invasive species that affect the health, the economy and the biodiversity of the islands of the Caribbean.

Back to Top