The tropical climate of the Virgin Islands provides suitable environmental conditions for year-round activity of many pest species.
The nearly continuous easterly tradewinds ensure quick drying of plant surfaces. Therefore, exposing as much of the foliage within a plant's canopy to air currents through selective pruning and adequate plant spacing will minimize infection periods for plant-disease organisms. Disease incidence and severity can thereby be greatly reduced.
Insects and other arthropod pests can become serious problems for plants, animals as well as man rather quickly.
Regular inspection of plants, animals and structures is often essential in avoiding economic damage by pest species.
Recognizing the pest problem* is the first major step in preventing further unwanted effects of the pests and control.
The geographical isolation of the Virgin Islands prevents the constant invasion by new pest species. Nevertheless, through various means including sporadic strong cross-atlantic air currents, new insect species may occasionaly reach the islands. A number of desert locusts (Schistocerca gregaria) reached the U.S. Virgin Islands in 1988 but, fortunately, did not become established.
Some insect pest species that have become established in the U.S Virgin Islands include the following.
- Sweet potato whitefly (Bemisia tabaci) (1980s) on many vegetable and ornamental plants and weeds
- Southern yellow thrips (Thrips palmi) (1990s) primarily on cucurbits
- Citrus blackfly (Aleurocanthus woglumi) (1990s) primarily on citrus
- Agave weevil (Scyphophorus acupunctatus) (1990s) on Agave and Yucca species - St. Thomas and Water Island only
- Avocado lace bug (Pseudacysta perseae) (1992) on avocado
- Africanized honey bee (Apis mellifera scutellata) (1994) St. Croix only
- Citrus leaf miner (Phyllocnistis citrella) (1996) on citrus
- Pink mealybug (Maconellicoccus hirsutus) (1997) on many food crops, fruit trees, ornamentals and weeds.
- Imported fire ant (Solenopsis invicta) (1998) St. Croix only
ADDITIONAL PROBLEM PEST SPECIES include
- Ensign coccids (Orthezia sp.) on a variety of fruit trees and ornamentals.
- Sugarcane borer (Diatraea saccharalis) on sugarcane.
THREATENING FOREIGN SPECIES include
- Mango seed weevil (Sternochetus mangiferae) on mango.
- Paracoccus marginatus especially on papaya and cassava.
Information on urban, plant and animal pests common to the U. S. Virgin Islands and control strategies is available from the UVI Cooperative Extension IPM office.
The application of pesticides is considered a control option used when no other method(s) will provide acceptable control. In the territory, pesticides, including home-made mixtures, are frequently used for insect pest control. As with any pest control method, pesticide application will only work if the right product is applied correctly. The Pesticide Applicator Training program provides instruction and other assistance to residents who apply general use as well as restricted use pesticides.
The extent of pest related damage in plant culture (food crops as well as ornamentals) is influenced by cultural practices such as fertilization, staking and pruning. Information on best practices is provided by the Urban Gardening and Sustainable Agriculture programs of the University of the Virgin Islands Cooperative Extension Service.
Information on Caribbean Insects
Lepidoptera of the French Antilles
Beetles of the Virgin Islands
For residents of the Virgin Islands who would like their pest problem identified, send a sample to the St. Croix Diagnostic Laboratory (Building D of the St. Croix UVI West-Campus) directly or through the St. Thomas or St. John UVI-CES Offices (St. Thomas: CES New House, next to golf course & Security Building; St. John: Above Joe's Discount Store). Submit with the sample the information requested in the Pest Identification Form (this form can be submitted directly from the form-page by e-mail).